International Society for Reef Studies
(ISRS)
European Meeting
4 th – 7 th September 2002
Abstracts Volume
Hosted by:
Cambridge Coastal Research Unit
Department of Geography
University of Cambridge.International Society For Reef Studies (ISRS)
ISRS European Meeting
Robinson College, Cambridge
4 th – 7 th September 2002
Host:
Cambridge Coastal Research Unit
Department of Geography
University of Cambridge
Abstracts Volume
Editors: S. Brooks, T. Spencer, K. Teleki and M.
Taylor
Local Organising Committee Scientific Committee
Sue Brooks, Birkbeck College University of London Colin
Braithwaite, University of Glasgow
Annelise Hagan, University of Cambridge Sue Brooks,
Birkbeck College University of London
Tom Spencer, University of Cambridge John Bythell,
University of Newcastle
Michelle Taylor, UNEP-World Conservation Monitoring
Centre Christian Dullo, GEOMAR
Kristian Teleki, University of Cambridge Marcos
Gektidis, University of Frankfurt
Edmund Green, UNEP-World Conservation Monitoring Centre
Jason Hall-Spencer, University of Glasgow
Jane Hawkridge, Mote Marine Laboratory
Piers Larcombe, James Cook University
Martin Le Tissier, University of Newcastle
Lucien Montaggioni, Universite de Provence
Chris Perry, Manchester Metropolitan University
Brian Rosen, Natural History Museum
Tom Spencer, University of Cambridge
Kristian Teleki, University of Cambridge
Sandy Tudhope, University of Edinburgh
Helge Vogt, Independent Consultant
Elizabeth Wood, Marine Conservation Society
Rachel Wood, Schlumberger Cambridge Research
Additional
support provided by the International Coral Reef Action Network (ICRAN).i
Table of Contents
Page
Abstracts: Plenary Addresses 1
Abstracts: Oral Presentations 5
Abstracts: Poster Presentations 113
Index of Authors 157.ii
Abstracts
Abstracts are presented in the order: plenary
addresses, oral
presentations and poster presentations. Abstracts for
both oral and
poster presentations are arranged by first author.
In most cases abstracts are printed as they have been
received and have
not been edited for content. Some ‘light editing’ of
titles and
affiliations has been carried out to ensure uniformity
of presentation.
Neither the Cambridge Coastal Research Unit, nor the
Organising/Scientific Committee of the ISRS European
Meeting accept
responsibility for content..Plenary Addresses..Plenary Address 1
Wednesday 4 th
September, 2002
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
1
REEFS
IN TURBID AND POLLUTED WATERS: WHY THE FUSS?
KATHARINA
FABRICIUS
Australian
Institute of Marine Science and Reef CRC
PMB
3, Townsville Qld 4810, Australia
k.fabricius@aims.gov.au
Great
beauty, high diversity and healthy recolonisation characterise the few turbid
inshore coral reefs
of
the Great Barrier Reef that remain in near-pristine condition. By contrast,
other inshore reefs are
severely
degraded, and some consider pollution, in the form of increased supply of
land-derived
nutrients,
sediments and pesticides, to be a major cause of their degradation. At local
scales, pollution
impacts
are well documented and accepted, however, at regional scales, pollution is
frequently
denied
to be a cause of reef degradation, and indeed causal links have been difficult
to demonstrate.
This
is due to factors such as (a) a lack of historic data, (b) high spatial and
temporal variability in
pollutants,
(c) the background of other forms of disturbances, and (d) non- linear
responses of
organisms
to pollution. Overall, pollution appears to be a lesser threat for coral reefs
than coral
bleaching
or destructive fishing. However, unlike many other forms of disturbances, many
pollutants
accumulate
and are stored in the system, thus system responses may become chronic once the
system’s
buffering capacity is exhausted.
Here,
I will examine various links between inshore reef degradation and pollution.
This will comprise
a
review of field and laboratory data from many parts of the world, followed by
presentation of new
experimental
and reef ecological studies. It will include the characterisation of the
ecological
properties
of near-pristine inshore reefs, and will contrast these with reefs frequently
exposed to river
plumes
from agricultural areas. I will then identify the two most likely mechanisms
for reef
degradation
in regions exposed to pollution. Additionally, potential secondary mechanisms
of
pollution
will be discussed, such as the enhanced survival of crown-of-thorns larvae,
which may have
profound
effects on the wider ecosystem.
Pollution
and reef degradation is a complex issue and there are many threads of evidence
of varying
strengths
to be considered, e.g. field studies with notoriously imperfect controls and
laboratory
experiments
that oversimplify natural systems. It is not surprising that simple hypothesis
tests are
unable
to resolve such complex questions. After all, it took decades of extensive and
expensive
research
until epidemiologists established sufficient weight of evidence linking
cigarette smoking
with
lung cancer– a link that is obvious in hindsight. As scientists, we need to
synthesize multiple
and
complex sources of information, weigh the evidence, quantify effect sizes, and
predict the
ecological
consequences and socio-economic costs of alternative actions. It is then up to
a better
informed
society to decide how much ecological change is acceptable..Plenary Address 2
Thursday 5 th
September, 2002
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
2
UNNATURAL
REEFS
JEREMY
B. C. JACKSON
Scripps
Institution of Oceanography
University
of California, San Diego
La
Jolla, California 92093-0244 USA
jbcj@ucsd.edu
Basic
ecological understanding of coral reefs is based on an unnatural mix of mostly
small species
whose
trophic relations are greatly distorted by overfishing. Large megafauna,
including fishes,
sharks,
sea turtles, crocodiles, sea cows, and seals have disappeared from entire reef
systems
worldwide.
Vertebrates in general are greatly reduced and comprise less than 2% of the total
free-living
animal
biomass on most reefs where the structure of food webs is dominated by very
small
fishes
and invertebrates. The habitat complexity of reefs and seagrass beds is also
greatly reduced
over
wide areas. Historical analyses demonstrate that virtually all reefs are
affected by overfishing
including
partially protected areas like the Great Barrier Reef. Historical trajectories
of the decline in
reef
ecosystems in the Indo-Pacific have the same slope as those from the tropical
western Atlantic.
The
only difference is the initial starting date of intense exploitation that was
much earlier in the
Atlantic.
Successful restoration and management require a more realistic and historically
informed
understanding
of the ecology of pristine coral reefs that can only be obtained by a
combination of
retrospective
analyses, modeling, and intensive studies of ecosystem structure and function
of the
very
few isolated reefs that have escaped intensive exploitation..Plenary Address 3
Friday 6 th
September, 2002
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
3
LINKING
ZOOXANTHELLA FUNCTION TO REEF HEALTH
ANGELA
E. DOUGLAS
Department
of Biology
University
of York,
York
YO10 5YW UK
It is
accepted that zooxanthella function, especially photosynthate release to the
coral, underpins
shallow
water coral reefs, and that the breakdown of the zooxanthella-coral symbiosis
at coral
bleaching
is a response to anthropogenic factors. A key development in recent years has
been the
appreciation
that zooxanthellae are not functionally uniform. The purpose of my talk is
twofold.
First,
the extent to which molecularly-distinct zooxanthellae vary in ecologically-
important traits,
including
photosynthetic parameters, susceptibility to bleaching and acclimatory
capabilities, will be
addressed.
Second, the ecological consequences of this variation at scales from the
individual colony
to
the reef will be explored, especially in the context of anthropogenic factors..Plenary Address 4
Saturday 7 th
September, 2002
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
4
ENVIRONMENTAL
VARIABILITY AND CHANGE:
HIGH
RESOLUTION RECORDS FROM CORALS AND CORAL REEFS
SANDY
TUDHOPE
Department
of Geology & Geophysics
Edinburgh
University
West
Mains Road, Edinburgh EH9 3JW,
Scotland,
UK
As
they grow, massive reef-building corals record environmental information in the
physical
structure
and chemical composition of their aragonitic skeletons. This attribute,
combined with
annual
skeletal growth bands, rapid growth rates, and colony longevity, makes corals
valuable
palaeo-environmental
archives, capable of yielding records with a temporal resolution of ± a few
months
over several centuries. In addition, since the aragonitic skeletons are
suitable for high-precision
U-series
and 14 C dating, analysis of ‘fossil’
corals provides an opportunity to extend the
records
back into the late Quaternary. These palaeoenvironmental records serve two
purposes.
Firstly,
corals may be used to extend beyond the instrumental record of environmental
change,
thereby
yielding crucial new insights into the coupled processes that control climatic
and
oceanographic
variability and change on decadal to millennial timescales. Secondly, the
records
provide
an essential context against which to view the current status and predicted
decline of modern
reefs.
A
major research effort has been directed towards reconstructing variability in
temperature, salinity
and
terrestrial run-off from analysis of annually-banded massive corals. In most
cases, chemical
tracers
in the skeleton are used as a proxy for the environmental parameter of
interest. These records
are
particularly powerful for investigating interannual variability. For example,
coral data has shown
that
the El Nińo Southern Oscillation climatic phenomenon has varied significantly
in its strength
over
time, with modern ENSO probably stronger than at any other time over the past
130,000 years.
Coral
geochemistry is also used to reconstruct variations in ‘mean’ conditions (e.g.,
change in mean
temperature,
salinity, rainfall etc.). This has proven to be more difficult, due to
uncertainties in
assumptions
about individual tracers. Nonetheless, significant progress is being made
through the use
of
replication of records and use of multiple and new proxies. For example,
combined trace metal
and
stable isotope measurements are producing consistent patterns of temperature
change on decadal
to
glacial- interglacial timescales; there is exciting new work on the use of
barium as a proxy for
suspended
sediment input to the coastal zone over the past few centuries (McCulloch et
al, this
meeting);
and coral growth rates are being successfully used to reconstruct SST change
over the past
few
centuries. Analysis of the structure, age and elevation of corals and coral
reefs also continues to
yield
new insights into the magnitude, timing, rates and mechanisms of sea- level
change on decadal
to 10
5 year timescales.
These
coral data are contributing to a picture of tropical environments that have
varied substantially,
and
rapidly, over much of the past few hundred thousand years. In many ways, the
last few thousand
years
appear anomalous, having relatively stable (warm) mean climate and sea- level,
but relatively
large
interannual (ENSO) variability. These data provide a crucial testing- ground
for models that
attempt
to predict future climate, and the impact of natural and anthropogenic
environmental change
on
coral reefs..Oral Presentations..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
7
SR/CA
IN CORAL ARAGONITE: IS NIGHT CARBONATE A GOOD INDICATOR OF SEA
SURFACE
TEMPERATURES?
Nicola
Allison, Adrian Finch
School
of Geography and Geosciences,
University
of St Andrews, Irvine Building, St Andrews, Fife KY16 9AL, UK
na9@st-and.ac.uk
Sr/Ca
in coral skeletons has potential as an indicator of past seawater conditions
but exhibits
geochemical
heterogeneity on a small spatial scale (<100 µm) that does not reflect
variations in sea
surface
temperature (SST) or chemistry. Skeletal Sr/Ca is affected by variations in
skeletal
calcification
rate which may be dependent on the photosynthetic activity of the zooxanthellae
in coral
tissue.
The skeleton deposited at night may be unaffected by these variations and may
be a more
reliable
indicator of SST (Cohen et al. 2001).
We
used secondary ion mass spectrometry with a 10 µm diameter analysis spot to
construct records
of
Sr/Ca in a Porites lobata specimen from Lanakai, Oahu, Hawaii. Analyses
were performed on
sections
cut perpendicular to the growth surface of the coral skeleton, spanning annual
bands. Parallel
tracks
were analysed following fasciculi (material deposited during the day) and
centres of
calcification
(deposited at night).
The
Sr contents of the day and night material follow similar seasonal trends but
are offset with night
carbonate
typically enriched by 350-400 ppm Sr. The day carbonate profile is
characterised by large
spiky
Sr fluctuations, which are deposited approximately days apart and are
superimposed on the
general
Sr seasonal trend. These fluctuations may relate to daily variations in coral
calcification rate
which
is in turn affected by light intensity and water temperature. The Sr range
observed in day
carbonate
(~900 ppm) is equivalent to ~5şC on the Sr palaeothermometer for Porites day
carbonate
(Cohen
et al. 2001) which is in good agreement with the observed seasonal
temperature range.
The
Sr range the in night carbonate profile (~600 ppm) is much larger than that
reported previously
and
is equivalent to ~16şC on the Sr palaeothermometer for night carbonate (Cohen et
al. 2001).
Calcification
at night is slower than in the day and previous studies suggest that the slope
of the Sr-SST
relationship
in night carbonate approximates to that seen in inorganic aragonite
precipitates.
This
is inconsistent with our data. While the Sr range in the night carbonate is
reduced compared to
that
of day material, some short term Sr spikes are still present. Sr varies by up
to 300 ppm over
distances
of <100 µm, which is nominally equivalent to <1 week skeletal growth. These
spikes do
not
reflect variations in SST. We suggest that while biological effects on Sr
incorporation are
minimised
in night carbonate, significant biological effects may still occur in this
material.
Cohen
AL et al., Kinetic control of skeletal Sr/Ca in a symbiotic coral: implications
for the
palaeotemperature
proxy, Paleoceanography, 16, 20-26, 2001..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
8
LONG
TERM CHANGES IN MALDIVIAN CORAL REEF COMMUNITIES
William
R. Allison
Coral
Reef Research and Management
Rangas
First Floor, Violet Magu, Henveyru, Male, MALDIVES
The
author has studied community change in Maldivian coral reefs since 1990. Rasdu
and Addu
Atolls
were repeatedly surveyed during the period 1991 to 2001. Included in the survey
sites at those
atolls
are sites surveyed during the Xarifa (1958) and Indian Ocean (1964)
expeditions. Survey
methods
included line intercept and point transects, video transects, photo-quadrats
and visual
surveys.
The different quantitative methods were tested to assure comparable results.
COADS SST
data
was obtained for the period 1980 – 2000.
Comparison
of 1991 survey data with the data obtained some three decades earlier showed
that large
declines
in coral cover had occurred at most of the Xarifa and IOE survey sites.
Acroporidae and
Pocilloporidae
had declined the most. Large areas of dead branching corals in growth position
were
also
observed in many other parts of Maldives. During the period 1991 – 1998 coral
cover generally
increased
in Rasdu and Addu although there was little change at most of the IOE sites in
Addu and
one
site in Rasdu. In April – May 1998 a large proportion of the corals in both
atolls and the
Maldives
died during a severe bleaching event. Hardest hit were Acroporidae,
Pocilloporidae, soft
corals
(except dendronepthids) and Millepora. Although mortality was very high,
"extirpations" were
not
observed. At a few locations coral cover and dominant type seemed to change
little in 1998, but
one
large patch of coral that had apparently survived since 1958 died in 1998.
Large massive coral
colonies,
especially Porites, declined significantly in abundance over the entire period.
Reef
bleaching and mortality in 1998 were highly correlated with elevated SST's in
April and May of
that
year. It seems probable that the elevated SST's and bleaching observed in 1988
contributed to the
state
of reef communities documented in 1991. Anthropogenic effects were also
involved in some
locations,
most clearly at Gan in Addu and probably at Veligandu in Rasdu..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
9
ALLOCTHONOUS
STORM GENERATES DISPLACED DAMAGE ON DEEP REEFS IN
BONAIRE
(N.A.)
Rolf
P.M. Bak, Gerard Nieuwland
Netherlands
Institute for Sea Research (NIOZ),
P.O.
Box 59, 1790 AB Den Burg, Texel, The Netherlands
Shallow
reefs were destroyed and deep reefs suffered high coral mortality by displaced
hurricane
effects.
Hurricane Lenny never came near the island of Bonaire (N.A.) but waves
generated by the
storm
hit the leeward coast of the island. There were three main effects on the
fringing reefs: 1 where
westerly
waves hit the reefs frontally all living organisms were cleaned off the reef at
depths from 0
to 6
m. 2 Dislodged corals, debris and coarse sediment was deposited between 6 to 20
m on the reef
slope.
3 Fine sediment (diam 100 µm) was transported to the reef at greater depth
(> 30 m). This
sediment
accumulated at the deep reef in front of the damaged shallow reefs and, through
deep lateral
transport
along the reef slope, also at locations that were unharmed in the shallow reef.
Sediment was
efficiently
cleared off living surfaces by most corals at the reef slope shallower than 25
m but not at
greater
depths. Surveys (random quadrats) at 35 m depth showed the impact of fine
sediment to
depend
on coral species, and high mortality of dominant species such as Agaricia
lamarcki. The deep
reef
may be a stable habitat in terms of wave movement but rare events such as
sedimentation will
cause
catastrophic damage..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
10
SYMBIONT
COMMUNITIES IN REEF CORALS FOLLOWING THE 1997-98 EL NIŃO:
WILL
RECOVERING REEFS BE MORE RESISTANT TO A SUBSEQUENT BLEACHING
EVENT?
Andrew
C. Baker, Craig J. Starger, Tim R. McClanahan, Peter W. Glynn
Wildlife
Conservation Society
Center
for Environmental Research and Conservation, Columbia University, MC 5557, 1200
Amsterdam
Avenue, New York, New York 10027, USA
Coral
bleaching as a result of sustained seawater warming is a major threat to coral
reef ecosystems
worldwide.
The long-term capacity of reef corals to survive these episodes is likely to be
dependent,
at
least initially, on the diversity and specific identities of the symbiotic
dinoflagellates
(“zooxanthellae”)
they contain. Because different algal symbionts appear to vary significantly in
their
susceptibility
to bleaching, we hypothesized that the symbiont community structure of coral
reefs
following
a severe bleaching event: (1) differs from that of the same reefs prior to
bleaching; (2)
more
closely resembles the community structure of reefs found at higher
temperatures; and (3) has a
higher
bleaching threshold than before and is consequently more likely to survive
future temperature
anomalies
of similar magnitude. We tested the first two of these hypotheses by using
Restriction
Fragment
Length Polymorphisms (RFLPs) in large subunit ribosomal RNA genes to identify
the
symbionts
of reef corals from Kenya (Indian Ocean), Panama (far eastern Pacific) and
Saudi Arabia
(Arabian
Gulf and Red Sea) after the 1997-98 El Nińo event. We found that scleractinian
corals in
Kenya,
Panama and the Arabian Gulf contained symbionts in two clades of Symbiodinium
(C and D).
The
high relative abundance of one of these clades (Symbiodinium D) in Kenya
and Panama,
combined
with its virtual dominance in high-temperature Arabian Gulf reefs and
comparative
scarcity
in Panama prior to the El Nińo, suggest this symbiont lineage may have global
importance in
determining
the response of reef corals to future thermal bleaching events. Red Sea reefs
that were
relatively
unaffected by bleaching contained relatively little Symbiodinium D but
also contained
significant
numbers of a third Symbiodinium clade (A), perhaps due to their
high latitude location.
These
results indicate that, although an absolute upper limit must exist, we should
not assume that
bleaching
temperature thresholds remain constant over time. Recent bleaching history,
regional
symbiont
diversity and time between bleaching events may be important factors in
determining the
long-term
response of coral reefs to global climate change..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
11
BLEACHING
AND LYSIS OF THE CORAL POCILLOPORA DAMICORNIS BY THE
NOVEL
PATHOGEN VIBRIO CORALLILYTICUS
Yael
Ben-Haim, Eugene Rosenberg
Department
of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life
Science,
Tel-Aviv University, Ramat Aviv 69978 Israel
yaelbh@post.tau.ac.il
Coral
bleaching and other diseases of corals have increased dramatically during the
last few decades.
A
high correlation has been reported between increased sea temperature and the
incidence of coral
diseases.
A new coral pathogen was isolated from diseased Pocillopora damicornis corals
near
Zanzibar
in the Indian Ocean. Based on its 16S rDNA sequence, genomic DNA fingerprinting
analyses,
and phenotypic characteristics, the pathogen was classified as a novel species
of Vibrio,
named
Vibrio corallilyticus. Infection of corals in controlled aquaria at 26-29°C, with a pure culture
of V.
corallilyticus caused tissue lysis of P. damicornis fragments. At 29°C, lysis began as small
white
spots after 3-5 days, rapidly spreading so that by 2 weeks the entire tissue was
destroyed,
leaving
only the intact bare skeleton. When an infected diseased coral was placed in
direct contact
with
a healthy one, the healthy coral lysed in 2-4 days, further indicating that the
disease was
contagious.
Inoculation with as few as 30 bacteria per ml was sufficient to infect and lyse
corals.
Seawater
temperature was a critical environmental parameter for the infectious process:
infection and
lysis
occurred rapidly at 27-29°C, slowly at
26°C but tissue lysis was not observed
at 25°C. At 24-25°
C,
pure cultures of V. corallilyticus caused bleaching of all 16 corals
infected within 2-4 weeks.
The
pathogen was reisolated from the diseased tissues of the infected corals.
Uninoculated control
corals
at 24-25°C showed no bleaching. The bacterial bleached corals contained less
than 12%
zooxanthellae
concentration compared to healthy corals.
During
the summer of 2001 when seawater temperature in the Red Sea (Eilat, Israel)
reached over
27°C,
there was considerable diseased corals. High numbers of V. corallilyticus were
found in
diseased
tissues, whereas it was not detected in healthy corals. V. corallilyticus was
found to be
geographically
distributed. Five additional strains of V. corallilyticus have been
isolated, three from
diseased
P. damicornis in the Red Sea, and aditional two strains from bivalve
larvae, from the
Atlantic
Ocean (Brazil) and Europe (Kent Region). These five strains showed high
genotypic and
phenotypic
similarities to V. corallilyticus type strain, and all were also
pathogenic to P. damicornis.
These
findings support the bacterial hypothesis of coral bleaching, and indicate a
relationship
between
temperature and the outcome of bacterial infection of corals..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
12
DETERIORATION
INDEX: A NEW APPROACH TO CORAL REEF MONITORING
O.
Ben-Tzvi, Y. Loya, A. Abelson
The
Institute for Nature Conservation Research,
Tel-Aviv
University, Ramat-Aviv, Tel-Aviv 69978, Israel
bentz@post.tau.ac.il
Coral
reefs are deteriorating globally. Concern to the future of coral reefs drove
governments, NGOs
and
scientists to enhance reef monitoring worldwide. Monitoring would be valuable
if it can point to
changes
in the state of the examined coral community. The value of this indication can
be especially
high
when deterioration begins, since at early stages of deterioration the chance of
reversing the
process
is higher. Some widely used monitoring methods compare coral community
parameters such
as
live cover, mortality rate, size-frequency distribution, species richness and
diversity. Coral
communities
differ naturally from each other due to their depth, location, exposure to
water flow and
their
history of disturbances. It is expected to find significant differences in all
of the above-mentioned
parameters
when comparing different coral communities. In many cases however, these
differences
are not indicative of the state of the coral community, do it remains stable or
is it
changing.
Only repetitive monitoring exactly at the same site can accurately and
objectively point out
if
the examined reef state is changing.
Here,
we suggest a practical approach that offers a solution to the above problem by
providing an
indication
of the relative state of the community in addition to an indication of the
trend of reef health
(developing
or deteriorating). This approach is based on an index (Deterioration Index; DI)
that
compares
community parameters (i.e. mortality and recruitment rates) within the community
as
opposed
to comparing the same parameter between different reefs.
The
DI was developed during a study of young coral communities developed on
artificially laid rocks
in
shallow water along the coast of Eilat (Gulf of Aqaba), where it was relatively
straightforward to
identify
the disturbed communities.
Subsequently,
we examined this method on natural coral reefs at Eilat and the Seychelles. The
DI
values
obtained at Eilat clearly indicate that some of the examined reefs are
experiencing
deterioration
while others are in a relatively reasonable shape. High DI values were
calculated for the
southern
part of Eilat’s Nature reserve (i.e. the Japanese Gardens) indicating a
declining community.
This
part of the Nature Reserve reef is of high species diversity and live cover.
However, the
recruitment
rate is very low and the mortality rate is relatively high. The DI, therefore,
indicates a
problem
despite the illusive image of a well-preserved reef community, as may be
misinterpreted
from
the high live cover and species diversity. This indication acquired from the DI
during a single
monitoring
occasion shows the same results obtained by the reserve management team, after
a long
term
monitoring.
Results
from the Seychelles surveys demonstrate that most reefs were severely damaged
during the
last
bleaching event. The DIs obtained there, show that most of these reefs are
rehabilitating.
However,
at some sites the DI values were quite high. Among them are sites that were
bleached and
now
have a high algal cover, and sites where the bleaching rate was relatively low
but now
experience
low recruitment. The results show that the DI approach can serve as an
efficient tool for
MPA
selection and management. This is due to the low-cost, fast-yielding and reliable
data, which
can
be obtained by inexperienced surveyors within a short-time (one hour)
training..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
13
CORAL
COMMUNITIES OF THE HADRAMAUT AND SHABWA PROVINCES, YEMEN
Francesca
Benzoni, Carlo Nike Bianchi, Carla Morri
Acquario
Civico e Stazione Idrobiologica di Milano
Viale
G. B. Gadio 2, I-20121 Milano, Italy
The
coral communities of the Gulf of Aden have been traditionally believed to be
sparse and poorly
developed
due to the effects of the cold, nutrient-rich water of the Arabian Sea
upwelling. Recent
studies,
however, have shown that they are actually significant and diverse. A survey of
the coasts of
Hadramaut
and Shabwa provinces, Republic of Yemen, in early 1998, found extensive coral
communities
at all hard-bottom sites examined along a 130 km stretch of coast, from Al
Mukalla
(14 o 31’N 49 o 9’E)
westwards to Belhaf (13 o 58’N 48 o 11’E). Due to the lack of detailed cartography
of
the
region, hard bottom sites were located within the study area by means of spot
check surveys.
Coral
communities were assessed using line intercept transects carried out at sites
with high coral
cover
at different depths. Coral life- form categories were recorded, while dominant
hard and soft
corals
were identified to genus level. A diverse array of coral communities was found
through the
study
area. The main type, particularly at depths greater than 4 m, was a high cover Porites
community,
typically composed of very large massive and sub- massive colonies. Large
monospecific
areas
of branching corals, especially Pocillopora damicornis, were common on
shallower hard
substrates,
a feature these coral communities share with those of Oman to the east.
Islands, both near-shore
and
offshore, tended to have better developed and more diverse coral communities
than were
found
fringing the mainland shore. The main factors influencing the presence,
structure and
composition
of coral communities in the study area seem to be the presence of available
substrate,
depth
and distance from the Arabian Sea upwelling. At the time of the 1998 survey the
Hadramaut
and
Shabwa coral communities were in excellent general health conditions, with no
sign of bleaching
mortality
in the recent past. True coral reefs have been reported to be very rare in the
northern Gulf
of
Aden, and this applies to our study area as well. Nonetheless, unexpected
extensive and high-cover
coral
carpets have been found in Hadramout and Shabwa. These surprising features of
coral
communities
in Yemen, as well as the striking patterns revealed in recent years in other
sites of the
Gulf
of Aden claim for further investigation in the whole area..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
14
PATTERNS
OF CORAL MORTALITY, SURVIVAL AND RECRUITMENT IN
MALDIVIAN
CORAL REEFS, FOLLOWING THE 1998 BLEACHING EVENT
Bianchi
C.N., Pichon M., Morri C., Colantoni P., Bernardini G., Benzoni F., Baldelli G.
Marine
Environment Research Centre, ENEA Santa Teresa
P
O Box 224, I-19100 La Spezia, Italy
The
1998 bleaching event, which followed abnormally high sea surface temperatures
(up to 34 °C),
caused
widespread mortality in the reefs of the Maldives. Mortality rates were highest
(approaching
100 %
in certain sites) for branching and tabular species of the genus Acropora, for
the
Pocilloporidae
and for the hydrocoral Millepora, particularly in shallow water.
Mortality rates were
lower
below 20 m and in general for massive species, for which colonies affected by
bleaching
mostly
displayed only partial discoloration of the tissues and death. No mortality at
all was observed
on
the octocoral Heliopora caerulea. A recent (April 2002) survey of coral
populations in 12 sites
(reef
slopes in inner and outer locations as well as within passes) has shown that a
majority of
colonies,
for nearly 140 species belonging to virtually all reef coral families and especially
Poritiidae,
Agaricidae,
Fungiidae, Mussidae and Faviidae, presented adult sizes and minor or no sign of
mortality
- an observation which suggests that most of them had survived the bleaching
event. Very
large
colonies of Porites sp.p. and Diploastrea heliopora have managed
to survive although only in
relatively
small patches over the whole colony, with average patch size ranging from 5 to
15 cm in
diameter.
Patterns of recruitment were followed through yearly surveys. As early as April
1999, two
different
size classes of Acropora had settled on the reefs. Largest recruits were
up to 14 cm tall,
suggesting
that the first wave of recolonization arrived soon after the mortality event.
No Pocillopora
recruits
were observed until 2000. In 2001, Pocillopora recruits were recorded
mostly above 5 m
depth
on the outer slopes and in the passes, with densities up to 5 recruits m -2 . The density of recruits
was
similar for Acropora, but the recruits were spread over a larger depth
range, and were also
observed
in other types of reef environment than outer slopes and passes. In 2002, the
abundance of
Acropora
recruits did not change, while a relative lower number of Pocillopora recruits
were
recorded.
Small- sized colonies (< 5 cm in diameter) were the most represented in both
years,
suggesting
renewed recruitment waves. A relative higher proportion of comparatively
large-size
colonies
(up to 25 cm in diameter for Acropora) would indicate rapid growth.
Faviidae, Poritidae and
Agariciidae
were the most abundant recruiters other than Acropora and Pocillopora,
and the genera
Pachyseris
and Leptoseris, in particular, showed the highest number of
non-branching recruits. No
Millepora
recruits have been observed to date. Overall, the se data allow for
cautious optimism with
respect
to the recovery capacity of Maldivian coral reefs following a major bleaching
event..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
15
SEA
-LEVEL CONTROL ON REEF ACCRETION:
THE
HISTORY OF RIBBON REEF 5, GREAT BARRIER REEF
C.
J. R. Braithwaite, H. Dalmasso , L. F. Montaggioni
Division
of Earth Sciences, Glasgow University, Glasgow G12 8QQ
A new
deep borehole, drilled to a depth of 210 mbsf (metres below sea floor), on
Ribbon Reef 5 on
the
Great Barrier Reef off Cooktown, NE Australia, reveals a shallowing- upwards
succession
punctuated
towards the top by a series of erosion surfaces. Reef accretion has been
controlled by the
response
of the system to changing sea level.
Carbonate
deposition began about 770 ka ago, during isotope stage 16, with a series of
debris flows.
These
reflect deposition on a relatively deep slope or ramp rather than a shallow
platform and are
represented
in the core from 210 to around 180 mbsf. Lithoclasts indicate that carbonate
deposition
began
in the area before the period represented by the cored succession, and was
followed by a
period
of lower sea-level that resulted in erosion. However, the cored succession shows
no evidence
of
erosion at these depths.
Overlying
carbonates, from 178- mbsf to 155 mbsf are fine-grained grainstones with few
relatively
large
coral fragments and rhodoliths dominated by melobesioids. These originated in
water less than
about
60 m deep but deposition was probably at greater depth. From 155 mbsf the
succession is
dominated
by locally coarse grainstones and wackestones, again with intervals of
rhodoliths. An
upward
transition from melobesioids to lithophylloids implies a progressive warming
and shallowing
of
waters, reflecting progradation of the platform margin. Downslope sediment
movement may have
resulted
from local oversteepening or storm activity on the shallower platform. The
corals present
from
120-95 mbsf imply derivation from shallower water, but steeply inclined laminae
suggest
continuing
downslope transport. Rhodoliths, Halimeda and symbiont-bearing benthic
foraminifera
indicate
derivation from waters less than 60 m depth.
Typical
reef assemblages were probably not established until about 100 mbsf depth in
the core,
isotope
stage 11. Grainstones are typical of the succession from 100-74 mbsf. Coral
fragments in
these
are predominantly of massive forms with bored surfaces and crusts of coralline
algae. They
suggest
derivation from quiet and/or relatively deep (15-30 m) water.
An
upwards transition to an assemblage of robust branching corals, is paralleled
by a change in the
dominant
algae, from melobesioids and lithophylloids to mastophoroids. These changes imply
a
progressive
shallowing, and deposits probably reflect reworking on a shallow slope. More
coral-bearing
limestones
were deposited during isotope stages 11 and 9. The lack of evidence of a
progressive
shallowing to emergence implies that the upper part of the succession has been
removed
by
erosion. The apparently unbroken succession to 36 mbsf and the lack of evidence
of emergence
below
this indicates a progressive accretion in which changes in sea level in the
vicinity of the
borehole
did not fall below the depositional surface..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
16
CHLOROPHYLL
AS AN INDICATOR OF NUTRIENT STRESS ON REEFS OF THE
GREAT
BARRIER REEF
Jon
Brodie, Michelle Devlin, Glenn De’ath
Australian
Centre for Tropical Freshwater Research
James
Cook University, Townsville, Australia
Phytoplankton
chlorophyll a has been monitored monthly since 1992 at 86 stations in
the Great
Barrier
Reef (GBR) lagoon. The stations are located on eight transects across the shelf
from 13 0 S to
23 0 S. A primary objective of the monitoring
program is to detect changes in the inshore environment
of
the GBR resulting from the rapidly increasing loads of nutrients being exported
from the
catchment
of the GBR. Data were analysed using generalized additive models and accounted
for
spatial
and temporal effects. In the analyses stations were grouped by ‘inshore’ (<
25 km from the
coast),
likely to be influenced by terrestrial runoff, and ‘offshore’ (> 25 km),
unlikely to be strongly
influenced,
and by five latitudinal regions of the GBR.
Strong
differences in chlorophyll a exist across the shelf with inshore
stations mean concentrations in
most
transects significantly greater than offshore except in the north. In northern
transects mean
chlorophyll
concentrations are low ( ~ 0.25 mg/L) both inshore and offshore. Mean
concentrations in
offshore
stations in the rest of the GBR are similar (0.15 – 0.27 mg/L) except in the
Capricorn region
in
the far south where offshore mean chlorophyll is 0.55 mg/L. In contrast to
northern transects
inshore
mean chlorophyll concentrations from Port Douglas south fall in the range 0.45
– 0.75 mg/L.
Strong
seasonal effects are evident with mean summer/wet season (December – April)
values ~ 50%
greater
than those in winter/dry season (May – November). Significant temporal patterns
in the data
over
the ten year period in each transect were observed and these may be correlated
with the
influence
of ENSO on river discharge but analysis of this possibility is not complete.
Mean
chlorophyll concentrations in inshore areas adjacent to catchments highly
developed for
agricultural
and urban uses are more than double mean concentrations in inshore areas
adjacent to
Cape
York catchments in the north which are largely undeveloped. Discharge of
nitrogen and
phosphorus
from developed catchments has increased approximately fourfold over the last
150 years,
with
the largest increase occurring in the last 50 years. Phytoplankton appears to
be responding to
this
enrichment. This signal of nutrient enrichment is of significance to the
ecosystem health of inner-shelf
reefs
of the GBR. In addition mean concentrations of chlorophyll above 0.6 mg/L in
the inshore
Townsville
to Port Douglas region of the GBR are relevant to theories which link the
initiation of
crown-of-thorns
starfish outbreaks to nutrient enrichment..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
17
FLORIDA’S
DEEP-WATER CORAL REEFS: PROTECTION, RESEARCH AND
RESTORATION
S.
D. Brooke, C. Koenig, C. M. Young
Harbor
Branch Oceanographic Institution, Fort Pierce, Florida 34946
The
Ivory Tree Coral Oculina varicosa, forms extensive bioherms or “banks”
of azooxanthellate
colonies
at depths of 70-100m along the edge of the Florida Hatteras slope. Healthy
reefs support
invertebrate
and fish communities as diverse as those of tropical coral reefs, and are a
critical
spawning
habitat for a number of commercial fisheries species. In 1984 the Oculina Banks
were
declared
a Habitat Area of Particular Concern (HAPC) and were protected from damaging
benthic
activity.
During the 1990’s it became apparent that despite protected status, large areas
of the banks
had
been physically damaged and fisheries were in decline. In 1994, the OHAPC
status was changed
to
Experimental Oculina Research Reserve to protect snapper and grouper
fisheries, and a coral
restoration
effort was initiated. Several types and configurations of concrete structure
were deployed
over
several years along damaged reef tract using large concrete structures. These
structures were
intended
to promote coral settlement in areas of denuded substrate, but after several
years, most
showed
no signs of coral recruitment. In 1998, study of reproduction and larval
development was
initiated
in order to assess natural re-colonisation potential and optimise restoration
efforts. Research
revealed
that O. varicosa is a gonochoristic broadcast spawning species, with
small eggs (~100mm)
and
an average fecundity of 850 (sd: 478) eggs per polyp. The gametogenic cycle
begins in the early
summer
and spawning occurs during late summer and fall, with no obvious relationship
to lunar or
tidal
phase. Planulae are small, approximately 160mm
in length, and settle approximately 21 days
after
spawning. Larval planktonic duration was integrated with hydrodynamic
information to
estimate
larval dispersal potential. It appears that larvae not only have the potential
to be transported
between
the deep reef tracts, but may also contribute larvae to near-shore
zooxanthellate populations
during
summer upwelling events. Preliminary genetic research supported ecological
evidence that
gene
exchange occurs between deep reefs and shallow water populations of O.
varicosa.
Unfortunately,
despite the protected status of the Oculina banks, and reproductive criteria
conducive
to
re-colonisation, the Banks have not recovered, and the healthy reef tracts have
been reduced to two
small
areas at the southern extent of the range. Possible explanations for the
continued demise and
lack
of regeneration of the Oculina reefs include illegal trawling, unknown
natural causes and very
low
coral recruitment rate.Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
18
STUDIES
ON THE ASSOCIATED COMMUNITIES OF SERPULA VERMICULARIS (L.)
REEFS
(POLYCHAETA: SERPULIDAE)
Nicola
Chapman, Colin Moore
Heriot
Watt University,
Riccarton,
Edinburgh, EH14 4AS
The
serpulid polychaete, Serpula vermicularis, is a common member of the
marine encrusting
community
in Europe. Throughout most of its range S. vermicularis occurs in the
form of individual
tubes
or occasionally as intertwining bundles of a few tubes, cemented to hard
substrata, such as rock
and
mollusc shells. However, at just three sites in northwest Europe massive reefs,
often exceeding a
height
of 50 cm and a width of 60 cm, they develop in shallow, sheltered waters.
The
greatest development of these serpulid reefs is found in Loch Creran, Scotland,
where their
presence
has been instrumental in the designation of Loch Creran as a Special Area of
Conservation
(cSAC)
under the EC Habitats Directive. This will necessitate the development of a
programme to
monitor
the status of the reef habitat, which is under potential threat from fishing,
aquaculture and
mooring
activities.
From
previous observations by divers it is believed that serpulid reefs provide a
habitat for a diverse
associated
community, although no detailed studies of the community have been published.
The aim
of
this study is to characterise the community, to provide a monitoring baseline
and to provide
information
to underpin the development of a monitoring strategy. The conservation
importance of
the
habitat will also be assessed by comparisons with the associated community of
other biogenic
reef
habitats.
Ten
entire serpulid reefs were removed by diver from Loch Creran, selected to
represent a broad
spectrum
of reef size. Reef size was measured in situ by determination of height
and width and in the
laboratory
by measurement of weight. Sessile and motile fauna and flora retained on a 0.5
mm screen
were
identified and counted.
The
presentation will describe the nature of the reef community and will illustrate
the relationship
between
reef size and community diversity and species richness. By employment of
multivariate
statistical
techniques the relationship between species composition of the community and
reef size
will
be examined. The conservation importance of the habitat will be discussed and
the implications
of
the work for future monitoring programmes established..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
19
TOWARD
CHARACTERIZATION OF MITOCHONDRIAL HEAT SHOCK PROTEINS IN
THE
SEA ANEMONE ANEMONIA VIRIDIS
Omer
Choresh 1 , Abdussalam Azem 2 , Yossi Loya 1
1 Department of Zoology, 2 Department of Biochemistry, George S. Wise
Faculty of Life
Sciences,
Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
omerch@post.tau.ac.il
Organisms
respond to stress, which causes damage to cellular proteins, by inducing
synthesis of Heat
Shock
Proteins (HSPs). Induction of HSPs is one of the most familiar mechanisms of
reaction to
various
stressful environmental conditions (e.g. adverse temperatures, increased UV
irradiation,
osmotic
stress and xenobiotics). These proteins play a major role in modulating protein
folding,
transport
and repair during normal conditions, with higher levels of their expression
being induced
under
stress. The relationship between environmental tolerance of organisms and the
expression of
HSPs
has been studied in diverse aquatic and terrestrial organisms. However, in some
groups of
organisms,
such as sessile marine invertebrates, some HSPs are not well characterized and
their
function
and significance to adaptation are not well understood. As a major step towards
characterizing
the stress response of marine invertebrates, we set out to develop general
protocols for
purifying
the mitochondrial (mt) HSP60 and HSP70 of the sea anemone Anemonia viridis. We
also
examined
the role of mt-HSP60 and mt-HSP70 in adaptation of marine invertebrates to
thermal stress
through
a study of the influence of changes in seawater temperature on the expression
of these
proteins
in A. viridis. Laboratory and field experiments reveal for the first time the existence
of mt-HSP60
and
mt-HSP70 in sea anemones; and furthermore, that their expression varies with
changes in
temperature.
A. viridis displayed high levels of both proteins when extreme temperature
conditions
(31°C) prevailed in stressful habitats, such as
tide pools. Further, we have developed purification
methods,
based on several chromatography columns and western blot analysis, fo r both
mt-HSP60
and
mt-HSP70. These methods allow purification of large amounts of the proteins for
further
sequence
analysis. We also found new antibodies that indicate changes in the expression
levels of mt-HSP60
and
mt-HSP70. Partial sequence data were obtained for the purified mt-HSPs. The
amino acid
sequences
for both proteins are homologous to amino acid residues of the mt-HSPs of
several
organisms,
including Drosophila and mammals, which show the proteins to be highly
conserved
between
organisms. However, these fragments showed less similarity when compared to
plastid
HSPs
from plants and to bacterial HSPs. We further found mt-HSP60 expression for the
first time in
various
marine invertebrates, including scleractinian corals. These results may be
particularly
significant
for coral reefs, which constitute one of the most spectacular and diverse
ecosystems on the
planet.
Our study may offer a useful tool for detecting mt-HSP60 and mt-HSP70 in marine
invertebrates,
and contributes to the understanding of the role of HSPs in the adaptation of
organisms
to
stressful environments. Identification of new HSPs of marine invertebrates is
expected to enable
rapid
and accurate quantitative monitoring of short-term and long-term fluctuations
in marine
ecosystems.
The importance of such research lies in using the expression of specific stress
proteins as
an
early warning system for changes in community structure in disturbed marine
habitats, and in
assessing
the ability of reef ecosystem to withstand global changes..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
20
CHARACTERISATION
OF THE BACTERIAL CONSORTIUM ASSOCIATED WITH
BLACK
BAND DISEASE IN CORAL USING MOLECULAR MICROBIOLOGICAL
TECHNIQUES
Rory
P. Cooney, Olga Pantos, Martin D.A. Le Tissier, John C. Bythell
Department
of Marine Sciences & Coastal Management,
Ridley
Building, University of Newcastle upon Tyne,
Newcastle
upon Tyne, NE1 7RU, UK
An
increasing number of reports have documented dramatic changes and continuing
declines in coral
reef
communities which have been attributed to both natural and anthropogenic
factors. It is widely
accepted
that diseases of reef corals are an important factor in determining coral reef
community
structure,
and that diseases may make a significant contribution to the observed coral
reef
degradation.
Although these diseases are a major ecological problem, their aetiology and
pathogenesis
is poorly understood. In fact, the overall knowledge of the microbial
communities
associated
with diseased and non-diseased corals remains poor, as most studies to date
were
constrained
by the limitations of traditional microbiological techniques based on
microscopy and
cultivation.
The
bacterial community associated with black band disease (BBD) of the
scleractinian corals
Diploria
strigosa, Montastrea annularis and Colpophyllia natans was
examined using culture-independent
techniques.
Two complementary molecular screening techniques of 16S rDNA genes
(Amplified
16S Ribosomal DNA Restriction Analysis [ARDRA] of clone libraries and
Denaturing
Gradient
Gel Electrophoresis [DGGE]) were used to give a comprehensive characterisation
of the
community.
Findings support previous studies indicating a low bacterial abundance and
diversity
associated
with healthy corals. A single cyanobacterial ribotype was present in all the
diseased
samples,
but this was not the same as that identified from Phormidium corallyticum culture
isolated
from
BBD. The study confirms the presence of Desulfovibrio spp. and
sulfate-reducing bacteria that
have
previously been associated with the BBD consortium. However, the species varied
between
diseased
coral samples. We found no evidence of bacteria from terrestrial, freshwater or
human
sources
in any of the samples. We report the presence of a previously unrecognised
potential
pathogen
(an a-proteobacterium identified as the etiological agent of Juvenile Oyster
Disease [JOD])
which
was consistently present in all the diseased coral samples. The molecular
biological approach
described
here gives an increasingly comprehensive and more precise picture of the
bacterial
population
associated with BBD..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
21
CONTRASTING
EFFECTS OF TEMPERATURE ON THE REPRODUCTION OF A
BROODING
SCLERACTINIAN AND BROADCASTING GORGONIAN FROM THE SUB-TROPICAL
CORAL
REEFS OF BERMUDA
Samantha
de Putron
Bermuda
Biological Station for Research
Ferry
Reach, St. Georges, GE 01, Bermuda
This
study examined the sexual reproduction of the brooding Scleractinian Porites
astreoides and the
broadcasting
Gorgonian Pseudoplexaura porosa in Bermuda. Variations in seawater
temperature at
the
study sites and across the years are related to a contrasting pattern of
temporal and spatial
reproductive
effort between the species. The lagoon of the Bermuda pseudo-atoll can be
divided into
three
physiographic reef zones that have different annual temperature profiles. The
temperature at
the
inshore reefs fell to 15.5 °C during winter and rose to 30.5 °C in the summer.
Oceanic waters
buffer
the outer rim reefs, which moderated the temperature range to 19-29 °C.
Inter-annual
variability
of seawater temperature profiles occurred over the study period, with summer
temperatures
in 1998 being relatively warm, those in 1999 being moderate and those in 2000
being
relatively
cool. P. astreoides released planulae in July and August of 1999 and
2000 from all three
reef
zones, extending into September both years at the cooler offshore reefs.
Overall, planulae
production
was greatest at the Rim Reef each year and an inclined temperature gradient is
shown
across
the reef zones to the Inner Lagoon with a corresponding decrease in
reproductive effort. There
is a
significant negative relationship between reproductive effort and the average
temperature for the
proceeding
month. There was no inter-zone difference detectable in P. porosa reproductive
effort;
however,
there was inter-annual variation. In 1998, when the temperature was slower to
rise and
remained
high throughout the summer, spawning occurred only during September and
October. In
1999
and 2000, when the temperature rose earlier in the year and remained high for a
short period,
spawning
was restricted to July and August. Reproductive effort was lowest in the cool
summer of
2000.
In contrast to P. astreoides, there is a positive relationship between
reproductive effort and the
average
temperature for the preceding month over the study years, although the
correlation is only
significant
for spermary production at the rim reef. The study of the reproductive biology
of corals in
Bermuda
is of particular interest because these reefs are the most northerly in the
Atlantic (32N
65W),
a distribution extreme for many species. The control of temperature on
reproductive cycles is
important
in the context of changing global conditions, increasing the need for a greater
understanding
of the effects of temperature on this sensitive part of the coral life cycle..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
22
CORAL
AND CORAL COMMUNITIES OF HONG KONG, CHINA 2001-2002:
ECOLOGICAL
VALUE, STATUS AND MANAGEMENT
Lyndon
M. DeVantier, Denise M c Corry
Australian
Institute of Marine Science, PMB 3, Townsville, Queensland 4810, Australia
We
undertook an ecological assessment of coral communities of Hong Kong in 2001-02
to assess
their
distribution, community structure and status, and to identify sites of high
conservation value.
Here,
corals and coral communities occur near the physico-chemical tolerance limits
for their
survival
and for reef growth. The communities exhibit strong gradients in distribution,
species
diversity
and abundance, all being highest in northeastern waters - more oceanic, being
further away
from
the estuarine influence of the Pearl River Delta. Hong Kong waters do not
support major reef
development,
rather the best developed coral communities form incipient reefs, but with
substantial
biogenic
accretion. Some of the coral communities are characterized by high coral cover
(> 50 %),
and
are comprised of a much richer coral fauna than known previously: 88 species in
30 genera of 12
families
of the Scleractinia, including approximately 45 new distribution records and an
undescribed
species
of the astrocoeniid Stylocoeniella. The corals form five major community
types with strong
geographic
and environmental affinities and key indicator species. Approximately one
quarter of
species
are ubiquitous, occurring in moderate - high abundance in more than one-third
of survey sites
and
across several of the community types. By contrast, over one third of species
have locally
restricted
distributions (occurring in < 10 % of sites) and low relative abundances,
and thus are
particularly
prone to local extinction following disturbance. Hong Kong’s naturally marginal
conditions
for coral and reef growth are exacerbated by turbidity, salinity and
temperature
fluctuations
(bleaching), predation, bio-erosion and further compounded by trawling
activity, fishing
traps
and nets, anchoring, sewage, dredging, dumping and land- fills. Minimizing the
controllable
local
impacts (trawling, netting, anchoring, run-off, pollution from local sources,
land- fills, dredging
and
dumping) through continued proactive management will help to sustain these
communities and
increase
their resilience to larger scale climatic impacts beyond local control. The
study demonstrated
that
the present marine parks were well selected in terms of conserving high quality
examples of two
coral-dominated
community types. Management recommendations include continued expansion of
the
established marine parks, development of additional marine parks encompassing a
coral-dominated
community
type not well represented in the park system at present, improved surveillance
and
policing of designated marine parks, continued implementation of ‘no anchor’
areas, raising of
community
awareness and other measures to help minimize human impacts at key sites..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
23
ASSESSING
PATCHINESS IN CORAL SURVIVAL FOLLOWING BLEACHING ON THE
GREAT
BARRIER REEF AND MODELING ITS IMPLICATIONS
Terry
Done 1 , Ray Berkelmans 1 , Roger Jones 2, Peter Whetton 2, Scott
Wooldridge 1
1 Australian Institute of Marine Science, PMB#3,
Townsville MC, Qld, 4810, Australia 2 Climate
Risk and Integrated Assessment Project, Climate Impact Group, CSIRO Atmospheric
Research,
Private Bag No.1, Aspendale, Victoria 3195 Australia
Impacts
of coral bleaching and patterns of survival of corals are patchy at spatial
scales from oceans
to a
single patch of reef. Reefs of the Great Barrier Reef are mostly several
kilometers in length and
breadth.
Following a bleaching event, their appearance and ecological structure in the
short term are
affected
by the relative abundance of coral species that are more and less
bleaching-prone. Coral
species
composition is also likely to affect each habitat’s future attractiveness and
productivity under
regimes
of increased frequency and severity of heat and light stress predicted to occur
with global
climate
change. We are exploring the likely appearance of the Great Barrier Reef in
coming decades
by
combining temperature monitoring, ecological assessments, a climate impact
model and an
ecological
disturbance and recovery model. Daily sea temperatures recorded at two AIMS
reef
weather
stations for a decade combined with Berkelmans’ bleaching threshold curves were
used in
the
CSIRO weather simulator ‘ReefClim’ to simulate various bleaching indices for
the years 2010,
2030
and 2050. Post-2002 ecological assessments of coral survival were used to
define six levels of
bleaching
impact, (from cosmetic to catastrophic) in terms of ‘set-back’ of the coral
community, and
to
link these to the bleaching thresholds predicted for the future. The future
scenarios generated for
coral
communities near the two AIMS weather stations will be presented, and the
sensitivities of the
modeling
approach discussed..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
24
DOES
COLOUR REALLY MATTER: HOST PIGMENTS AND BLEACHING?
Sophie
Dove
Centre
for Marine Studies, University of Queensland,
St
Lucia, QLD 4072, Australia
Recently
it has been suggested that host pigments may reduce the susceptibility of
reef-building
corals
to bleaching by offering their symbiotic dinoflagellates shade. Whilst elevated
temperature is
the
primary cause of bleaching, the rate at which corals bleach has been shown to
be faster under
higher
levels of irradiance. In an experimental study with three colour morphs of Acropora
aspera
collected
from adjacent positions on the reef flat of Heron Island GBR, we demonstrated
that a
heavily
pigmented coral morph whilst offering greater shade to their symbionts,
bleached at a faster
rate
than less pigmented morph and underwent significantly higher mortality if left
to recover for a
month
after heat is withdrawn. The experimental data suggests that the response to
temperature of
these
three colour morphs was highly variable with differential rates of
zooxanthellae and/ or tissue
loss.
Cytochrome b analysis of host failed to discriminate colour morphs and gross
cladistic analysis
of
symbionts revealed no distinctions. The properties of bacterially expressed
host pigments suggest
a
novel shading mechanism for these pigments that could be significantly affected
by elevated
temperature..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
25
PREDATOR
REMOVAL CAUSES PHASE SHIFTS
Nicholas
K. Dulvy, R. E. Mitchell, N.V.C. Polunin
Department
of Marine Sciences & Technology
University
of Newcastle-upon-Tyne
Newcastle-upon-Tyne,
NE1 7RU, UK
The
search for ecosystem features and processes that maintain resilience remains
the Holy Grail of
ecology.
The traditional view is that 'bottom up' factors such as recruitment, nutrients
and disturbance
drive
the structure and functioning of producer communities, e.g. corals and algae.
More recently,
theory
suggests ecosystem resilience is maintained by numerous weak trophic links
among species.
But
in reality a few strong links between predators and producers (known as trophic
cascades) may
also
exist. On reefs, the fulcra linking predators and producers are either
herbivorous urchins, or the
coral-
feeding starfish Acanthaster planci. These relatively strong trophic
cascade interactions have
the
potential to short circuit energy flow throughout ecosystems resulting in a
phase shift and
therefore
reducing resilience. While the importance of 'top down' predatory control for
ecosystem
resilience
has been suspected for a long time, the evidence has been elusive. We
demonstrate
increasing
densities of Acanthaster along a gradient of increasing fishing
pressure, consisting of 13
Fijian
islands. At the two most heavily fished islands, with lowest predator
densities, the benthic
communities
had phase shifted from domination by calcifying organisms to domination by non-calcifying
organisms,
e.g. algae, sponges, soft corals. We theoretically demonstrate how fishing
reduces
coral reef resilience by removing predatory controls of starfish populations..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
26
CHANGES
IN DIFFERENT FORMS OF CELL DEATH ACTIVITY OVER TIME IN
RESPONSE
TO DIFFERENT AMOUNTS OF HYPERTHERMIC STRESS DURING
EXPERIMENTALLY
INDUCED BLEACHING OF THE SYMBIOTIC SEA ANEMONE
AIPTASIA
SP.
Simon
R Dunn 1 , Jeremy C Thomason 2 , Martin D A LeTissier 2 , John C Bythell 2
1 School of Biological Sciences, University of
Liverpool, Life Sciences Building, Crown Street,
Liverpool,
L69 7ZB, UK
sidunn@liv.ac.uk
2 Centre for Coastal Management and Marine
Sciences, School of Biological Sciences,
University
of Newcastle upon Tyne, Claremont Rd, Newcastle upon Tyne, NE1 7RU, UK
Changes
in activity of different forms of cell death in the symbiotic sea anemone Aiptasia
sp. were
measured
in response to different amounts of hyperthermic stress over time. Programmed
cell death
(PCD)
and cell necrosis activity within the host and zooxanthellae were identified
using established
techniques
(Dunn et al. 2002). The results indicated the amount of cells undergoing
PCD within
anemone
host tissue increased from an underlying cell turnover rate within hours of
treatment. The
increase
in PCD activity was temperature dependent and correlated to the onset of
zooxanthellae
release
from degraded endoderm. As different temperature treatments continued, the
level of PCD
declined
and the amount of cell necrosis increased indicating a thermal threshold for
PCD activity.
Both
PCD and cell necrosis of zooxanthellae increased exponentially, from an
underlying cell
turnover
rate, with time in all temperature treatments. Host cell degradation,
zooxanthellae release
and
degradation was correlated to bleaching in response to different amounts of
hyperthermic stress.
Changes
in activity of programmed cell death pathways within host cells and
zooxanthellae is
important
to the understanding of bleaching events, raising interesting questions
regarding the
evolution
of this process and the activation of the cellular trigger mechanisms involved.
S.R.
Dunn, J.C. Bythell, M.D.A. Le Tissier, W.J. Burnett, J.C. Thomason (2002)
Programmed cell
death
and cell necrosis activity during hyperthermic stress- induced bleaching of the
symbiotic sea
anemone
Aiptasia sp. J. Exp. Mar. Biol. Ecol., 272 (1) 29-53..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
27
RESULTS
OF THE “CONTRAST” PROJECT:
TRANSPLANTATION
OF CORAL FRAGMENTS FROM SHIP GROUNDINGS ON
ELECTROCHEMICALLY
FORMED REEF STRUCTURES - TOOLS FOR REEF
REHABILITATION?
Eisinger,
M., Paster, M., van Treeck, P., Schuhmacher, H.
Institute
of Ecology, Dpt. Hydrobiology
University
of Essen
45117
Essen
Germany
We
report here on a research project aiming to develop rehabilitation measures for
mechanically
degraded
reef areas with a minimum of environmental harm and interference with living
resources.
The
CONTRAST project (COral Nubbin TRAnsplantation STudy) –
jointly run with the Egyptian
Environmental
Affairs Agency (EEAA) and the Ras Mohammed National Park authorities – mainly
focuses
on the application and further development of an environmentally friendly
technology for
reef
rehabilitation including trials to select suitable coral species for
transplantation.
We
used the ERCON (Electrochemical Reef CONstruction) technology to
build the substrate for
coral
transplantation. Through electrolysis, minerals from the seawater, mainly
calcium carbonate,
can
be precipitated onto a given matrix (preferably made of steel mesh) by
connecting the mesh as
cathode;
a titanium grid serves as anode. Installations with various designs were
applied to follow the
development
of the coral transplants.
Coral
fragments (“nubbins”) were derived from ship groundings and other damaged reef
sites. In
total,
597 nubbins were transplanted: 506 acroporids (Acropora hemprichii, A.
digitifera, A.
eurystoma,
A. granulosa, A. squarrosa, A. valida, A. hyacynthus, A. cytherea, A.clathrata)
and 91
milleporids.
Despite heavy grazing by the coralivorous snail Drupella cornus and
strong algal
blooms
during spring time 65% of all nubbins survived the first year. The lowest
mortality rates were
observed
in Millepora dichotoma (2%), Acropora hemprichii (19%) and A.
eurystoma (18%). Axial
growth
rates significantly varied between species. Among the acroporids, A.
hemprichii exhibited the
highest
values (19,4 mm/year), Millepora dichotoma grew 14,2 mm/year. All
nubbins developed a
strong
holdfast at their bases by overgrowing the grid and were hereby fixed in
addition to the
electrochemical
accretion process itself. Some nubbins extended their bases over more than 25
cm˛.
The
promising results could be the base for the creation of “stepping stones”
characterized by stable,
spaciously
heterogeneous substrates carrying donor colonies transplanted onto these small
“protoreefs”.
These protoreefs are intended to serve as receiver and provider of coral
recruits. In this
way,
the dispersal of sexual propagules could be enhanced over a large area. Apart
from the
application
of completely new structures in degraded reef areas (as demonstrated in this
study) single
units
could be inserted as “reef prostheses” in partially impoverished reefs..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
28
FACULTATIVE
CORALLIVORY BY THE CUSHION STARFISH PENTACERASTER
CUMINGI,
GALÁPAGOS ISLANDS, ECUADOR
J.
S. Feingold
National
Coral Reef Institute, Nova Southeastern University Oceanographic Center, 8000
North
Ocean Drive, Dania Beach, FL, 33004, USA
joshua@nova.edu
The
cushion starfish Pentaceraster cumingi was observed feeding within a
free- living coral
community
located adjacent to Devil’s Crown, Galápagos Islands, Ecuador. Here, numerous
individuals
of the fungiid coral Diaseris distorta and unattached branching colonies
of Psammocora
stellata
occur in 15m depth on calcareous sand and coral rubble substrata. Of 440 Pentaceraster
seen
within
the coral community during 13 different observation periods 58.2% were feeding
(cardiac
stomach
everted onto substratum and/or coral) and 41.8% were not feeding. During 4
observation
periods
39 Pentaceraster displayed strong avoidance of Diaseris individuals
and preferentially
consumed
colonies of Psammocora. Although Diaseris composed 29% of the
bottom cover around
these
feeding Pentaceraster, it was a food item 5% of the time. In contrast, Psammocora
composed
36%
of the bottom cover, but was a food item 64% of the time. No preference was
shown for feeding
on Psammocora
skeletons that commonly supported growths of macroalgae, bryozoans and
other
encrusting
macro-invertebrates. Dead Psammocora composed 32% of the bottom cover
and was a
food
item 31% of the time. The relative importance of Pentaceraster corallivory
in this community
will
be assessed with special reference to coral population dynamics following
disturbances
associated
with El Nińo-Southern Oscillation..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
29
SIGNATURES
OF LARGE-SCALE ATMOSPHERIC TELECONNECTIONS IN MIDDLE
EAST
CORAL RECORDS
Thomas
Felis 1 , Jürgen Pätzold 1 , Henning Kuhnert 1 , Saber A. Al-Rousan 1,2 , Salim M. Al-Moghrabi
2 , Gerold Wefer 1
1 Fachbereich Geowissenschaften, Universität
Bremen,
Klagenfurter
Str., 28359 Bremen, Germany 2 Marine
Science Station, P.O. Box 195, Aqaba 77110, Jordan
The
northern Red Sea is one of the rare locations where massive annually banded
corals grow at 28-29°
N. A
coral oxygen isotope record from this subtropical region revealed the strong
influence of
mid-
to high- latitude climatic modes on Middle East climate variability during the
past 250 years. An
oscillation
with a period of 5-6 years in the coral record reflects atmospheric
teleconnections
associated
with the Arctic Oscillation/North Atlantic Oscillation, the Pacific Decadal
Oscillation, but
also
with the El Nińo-Southern Oscillation.
Fossil
corals from the northern Red Sea provide the opportunity to investigate whether
these
teleconnections
where active during selected time windows throughout the late Quaternary. A
5-6-year
periodicity
is detected in a 44- year coral oxygen isotope record from the last
interglacial period.
This
could indicate Arctic Oscillation- like atmospheric variability during Marine
Isotope Stage 5e.
With
respect to late Holocene climate variability a new 100-year coral oxygen
isotope record from
about
3000 calendar years BP will be presented.
The
application of the coral Sr/Ca paleothermometer in conjunction with oxygen
isotopes indicates
cooler
and fresher mean conditions in the northern Red Sea during the last
interglacial, with a higher
sea
surface temperature seasonality of about 50%. Coral records for time windows
during the mid-Holocene
indicate
an increased seasonality in the hydrologic balance between 6000 and 4500
calendar
years BP.
Felis
et al. (2000), Paleoceanography 15, 679-694.
Rimbu
et al. (2001), Geophysical Research Letters 28, 2959-2962..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
30
EXCESSIVE
SEDIMENTATION AND REEF DEGRADATION, MOLOKA’I, HAWAI’I
Michael
E. Field, M. Bothner, E. Brown, S. Cochran, P. Jokiel, A. Ogston, C. Storlazzi,
US
Geological Survey, Pacific Science Center,
1156
High Street, Santa Cruz, CA, 95064 USA
Terrigenous
sediment run-off and deposition on coral reefs is recognized to potentially
have
significant
impact on coral condition in Hawai’i and other high islands in the tropical
Pacific and
Caribbean.
Human habitation of these islands has resulted in significant changes in the
drainage
basins
and to coastal areas, and these changes have in turn influenced the volume of
terrigenous and
carbonate
sediment released to the reefs. Within the past century, significant changes in
land use have
accelerated
the amount of sediment transported to and stored on the reef off south
Moloka’i.
Deforestation,
agriculture, domestic and feral grazers, hillside housing construction, and
coastal
development
have exacerbated historical run-off of sediment.
The
south coast of Moloka’i contains an extensive fringing reef nearly 50 km in
length, the longest
and
most extensive reef tract in the Hawaiian Islands. The reef exhibits a richness
and density of live
coral
that are amongst the highest in the islands; many areas of the reef exhibit
more than 80 % live
coral
cover. A contributing factor to the success of corals in constructing a major
reef structure on
south
Moloka’i is its setting. The reef is protected from damaging northerly storms,
from persistent
northeast
trade winds, and from most southerly swell events by its south- facing exposure
and
shielding
by neighbor islands.
Our
approach to understanding sedimentation and its impact on the Moloka’i coral
reef system
includes
three primary efforts: mapping terrigenous deposits and their sedimentologic
and
geochemical
characteristics; measuring relevant processes that inject and redistribute
sediment to the
reef
system; and real- time monitoring of sedimentation “events” on the reef.
The
inner most reef flat (within 50 m of the shoreline) is characterized by a 10-
to 30-cm thick
muddy
sand layer. Farther seaward (>500 m) sediment thickness over the hard
substrate is highly
variable
(0 to 50 cm, and in places > 1.0 m) owing to the variation in relief of the
ancestral reef
platform.
Areas of exposed limestone and exposed old coral ridges are barren of sediment
and
intervening
low areas and small reef holes are sites of accumulation. Mud, mostly
terrigenous in
origin,
dominates in the nearshore zone; elsewhere on the reef flat sediment is mostly
carbonate sand
with
minor amounts of admixed terrigenous-carbonate mud.
Terrigenous
mud is transported to the coast during major rain events that occur on annual
to decadal
time
scales. Fine sediment deposited on the reef flat is trapped in a ~200- m wide
belt where it resides
for
periods of years to decades. Measurements of waves, currents, turbidity show
that a portion of the
fine
sediment stored on the reef flat is resuspended daily by trade wind waves
occurring during high
tides.
Thus fine sediment is effectively recycled and small additions have repeated
effects in blocking
light,
abrading and mantling live coral, and decreasing recruitment sites. An added
impact from
hillside
erosion is an apparent increase in nutrients associated with sediment
particles, which leads to
rapid
growth of fleshy algae. Some impacted areas of the reef during the last century
now appear to
be
recovering, while others are not..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
31
COLONY
INTEGRATION AND RESOURCE TRANSLOCATION DURING CORAL
BLEACHING
Maoz
Fine, Yossi Loya
Department
of Zoology, Tel Aviv University, Tel Aviv, 69978 Israel
Bleaching
of corals results in the loss of their symbiotic algae (zooxanthellae) and/or
their pigments.
Coral
bleaching is often linked to global climate change, especially elevated
seawater temperature and
high
solar irradiance. When the coral loses its zooxanthellae, it loses its main
energy resource, putting at
risk
its essential biological functions. Certain coral species survive severe
bleaching events better than
others,
leading to major structural shifts in some coral communities. One of the most
intriguing
questions
consequently being asked by coral reef researchers is why are some coral
species more
resilient
to bleaching events and better survive them than others?
Integration
within hermatypic corals has long been the focus of scientific interest.
Resource integration
is a
basic life-preserving ability and one of the most important advantages of
clonal and colonial
organisms.
Nevertheless, this ability has never been investigated in corals undergoing
bleaching. In the
present
study, we focused on resource integration and translocation of 14 C-labeled photoassimilates in
the
temperate Mediterranean stony coral Oculina patagonica during and
between bleaching events.
Using
point labeling ( 14 C) techniques, we
labeled healthy parts of the colony and examined oriented
translocation
of photoassimilates towards regions of high demand, such as regions of the
colony that
undergo
lesion repair and regions interacting with competing neighboring organisms. In
each
experiment,
we labeled colonies at different bleaching stages. Lesion recovery rate,
competitive abilities
with
neighboring organisms and translocation of photoassimilates during these
processes were studied at
different
bleaching stages. We have showed that lesion recovery and competitive
superiority are coupled
with
oriented resource translocation. We also found the existence of a bleaching
threshold that
postpones
intra-colonial integration in O. patagonica at bleaching percentage
greater than 40%.
Bleached
colonies of O. patagonica with >40% bleached surface area showed low
resource integration
and
low translocation rates of photosynthetic products. This is reflected in low
lesion recovery rates of
bleached
colonies and competitive inferiority (with neighboring organisms) of bleached
colonies
compared
with non-bleached colonies. At the same time, it is possible that such
disintegration between
the
healthy sections of the colony and the bleached ones contributes to overall
colony survival by
preserving
the resources within the section with greatest chances of recovery after the
bleaching event.
Indeed,
over 90% of bleached O. patagonica colonies survive and recover from
bleaching during winter.
We
suggest that coral species with low bleaching threshold are better survivo rs
of bleaching events as
they
cease translocation of resources at earlier stages of bleaching, maintaining a
reservoir of resources
for
survival and recovery..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
32
CORAL
CHROMOSOME NUMBERS: TESTING THE RETICULATE EVOLUTION
HYPOTHESIS
Jean-François
Flot, Makoto Tsuchiya
Department
of Chemistry, Biology and Marine Science, University of the Ryukyus
Senbaru
1, Nishihara, Okinawa 903-0213, Japan
Human
cells contain 23 pairs of homologous chromosomes; this chromosome number is an
invariant
of
our species. Much information regarding our biology can be read directly by
looking at our
chromosomes:
for instance, biological gender depends in most case on the presence or absence
of
sexual
chromosomes, recognizable by their shape. The origin of our species can be
inferred from the
morphological
comparison of our chromosomes with the ones from apes and monkeys. In plants
such
as
wheat, loss and gain of chromosomes and hybridization lead to network- like
(and not tree-like)
phylogenies.
In
spite of the huge interest on chromosomes numbers and morphologies in other
groups of living
organisms,
there is little information available concerning scleractinian coral
chromosomes. Up to
now,
chromosome numbers in tropical reef corals have only been published for 29
species out of
about
800, which represents less than 4%. These researches have addressed so far only
6 genera (out
of
about 110), in 3 families (out of 18) (Heyward 1985; Kenyon 1997).
Existing
protocols all make the task of determining chromosome numbers very cumbersome
and
time-consuming,
as the starting material is living coral embryos and the method yields only a
small
fraction
of exploitable chromosome preparations. In this research, we have been trying
to improve
existing
protocols and to find new methods to quickly produce accurate and reliable
chromosome
preparations
that may allow us not only to determine chromosome numbers but also to study
their
morphologies.
Coral
embryos were collected at James Cook University’s Orpheus Island Research
Station, in the
central
section of the Great Barrier Reef Marine Park (North Queensland, Australia),
from December
1 st to 12 th ,
2001; at the Akajima Marine Science Laboratory, Japan from May 26 th to June 2 nd ,
2002;
and
at the Hawaii Institute of Marine Biology at Coconut Island, Oahu, from June 16
th to August 14 th ,
2002.
10-11 hours embryos were put in seawater containing 3% colchicine for two
hours, which was
followed
by a 30- minute osmotic shock treatment in a mix of 65% seawater and 35% tap
water.
Embryos
were then fixed and their chromosomes observed using a wide array of different
methods.
Heyward,
A. (1985). Proc. 5th Int. Coral Reef Congress, Tahiti, 1985, vol.6: 47-51
Kenyon,
J.C. (1997). Evolution 51(3): 756-767
Acknowledgments:
J.-F.F's
research was supported by a scholarship from the Japanese Ministry of Education
(Monbusho)
and by a research grant from the PADI Project Aware Foundation...Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
33
EXPERIMENTAL
ASSESSMENT OF THE INFLUENCE OF SETTLEMENT STRATEGY
ON
PREDATION ON CORAL REEF FISH
Galzin
René, Lecchini David
Ecole
Pratique des Hautes Etudes – UMR CNRS 8046
Université
de Perpignan
66860
Perpignan cedex – France
lecchini@univ-perp.fr
The
settlement stage of coral reef fish, period during which larvae coming from the
ocean take up
residence
in a particular population, represents a relatively short time (just a few
weeks) in the life
cycle.
But it has been proposed as the crucial stage of the life cycle, because it can
determine the
dynamic
and structure of the adult communities. This stage is characterised by the high
mortality of
coral
reef fish new settlers (80 to 95 % of the population decrease by predation
within one to two
months)
and by a specific settlement strategy (selective choice of suitable habitat).
In the present
work,
we investigate the influence of specific factors of settlement strategy
(shelter availability,
interaction
with conspecifics or competitors, and density of new settlers colonising the
lagoon) on
predation
on coral reef fish new settlers. We choose to use Chromis viridis of 10
mm (fish just
settled)
and 20 mm long (fish already adapted in the reef) as study model. Our results
demonstrated a
significant
variation in the mortality of 10 and 20 mm new settlers according to
substratum. This
influence
may be due to the characteristics of shelter: adaptability of shelter to the
size of the new
settlers,
quality of shelter which corresponds to the possibility of access to the
habitat for the fish, and
acclimatization
of fish to an artificial habitat, identical to their natural habitat.
Alternatively,
predation
could inhibit interaction between conspecifics and competitors during the
settlement stage,
when
predation pressure is strong on the new settlers. Finally, the density of new
settlers could
influence
predation (density-dependent mortality) whe n the density is high. But when the
density
becomes
low, this mortality does not seem to be influenced by the density of new
settlers (density-independent
mortality).
This means that, according to the larval supply, either the density-dependent
mortality
(pattern of competition) or the density- independent mortality (pattern of
recruitment
limitation)
determines the juvenile population stock. This study, then, shows this high
mortality by
predation
and the determinant factors of settlement strategy influence each other, and
thus determines
the
dynamic and structure of the adult communities. This conclusion also finds a
field of application
in
projects of coral reef replenishment..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
34
INSTITUTIONAL
EVALUATION OF CARIBBEAN MPA’S AND OPPORTUNITIES FOR
PRO-POOR
MANAGEMENT
Caroline
Garaway, Nicole Esteban, Vicki Cowan
Marine
Resources Assessment Group Ltd
47
Princes Gate, London, SW7 2QA, UK
In
the Caribbean, MPA’s are seen as a prominent means of addressing coastal
resource management.
Ecological
impacts of MPA's have been well researched and are usually shown to be positive
for
biodiversity
(Dixon et al., 1993) and fisheries management (Roberts and Polunin,
1993; Wantiez et
al.,
1997). Amongst advocates of MPA’s there has been a tendency to extol their
potential value in
socio-economic
terms. In reality, the establishment of protected areas often generates deep
resentment
in communities that find themselves excluded from resources to which they have
traditionally
had access, undermining the viability of those protected areas (Horrill et
al., 1996).
Over
the last ten years, management of MPA’s has evolved from being a preservation
tool to
integrating
considerations of development, sustainable use of resources and stakeholder
participation
(Meffe
et al., 1997). With this focus, it is believed that they can play a key
role in conserving natural
ecosystems
and contribute substantially to sustainable development (IUCN, 1997).
The
purpose of this research is to identify current institutional constraints to,
and development
options
for, successfully implementing MPA’s in a way that leads to a sustained
improvement in the
livelihoods
of poor people in the Caribbean. A key premise of this work is that successful
implementation
and beneficial stakeholder outcomes, inc luding outcomes for the poor, are
inextricably
linked and priority will be given to understanding the dynamic relationship
between
processes
and outcomes. Particular attention has been paid to systems that include
community
participation
in decision- making to see what benefits this brings to the poorer groups and
to
understand
the structures and processes needed to achieve it.
An
initial review of institutional and ecosystem characteristics of 80 MPA’s in
the Central and
Antillean
biogeographic zones of the Caribbean took place mid 2001 (Geoghegan et al.,
2001) and
was
succeeded by an analysis of operational and non-operational MPA case studies in
Belize,
Jamaica,
Turks & Caicos Islands and Dominica to investigate factors contributing to
successful and
unsuccessful
outcomes of MPA management. The participatory basis to all methods of enquiry
and
series
of facilitated workshops has brought researchers and a range of stakeholders
together to
address
key issues and explore solutions. Research at the operational MPA case studies
involved
evaluation
of the impacts of successfully implemented MPA management on poor people’s
livelihoods
and included PA (participatory appraisal) exercises (e.g. wealth and well
being; trends in
capital
assets; changes in livelihood opportunities; ease of access to local institutions
to improve
livelihood
options) to understand poorer groups’ perceptions of MPA impacts. A series of
biophysical
studies were undertaken by the University of the West Indies (UWI) to assess
the
environmental
sustainability of MPA’s. A legal review was also conducted to understand how
the
external
policy environment influences MPA management.
This
presentation will explore research findings, including the overall review of
institutional and
ecosystem
characteristics of Caribbean MPA’s and a more in-depth evaluation of the
factors
contributing
to successful and unsuccessful outcomes of MPA management and evaluation of the
impacts
of successfully implemented MPA management..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
35
GLOBAL
DISTRIBUTION OF MICROBIOERODERS AND THEIR NORTHERNMOST
TROPICAL
REEF COMMUNITY AT 30 O N – EILAT,
ISRAEL
Gektidis,
M.1 , Chadwick-Furman, N. E.2 , Goffredo, S.3 , Dubinsky, Z. 2
1 Geologisch Paläontologisches Institut, J.W.
Goethe Universität, Senckenberganlage 32-34,
60054
Frankfurt am Main, Germany, science@gektidis.de 2 Faculty of Life Sciences, Bar Ilan University, Ramat Gan 52900,
Israel, and Interuniversity
Institute
for Marine Science, P. O. Box 469, Eilat 88103, Israel. 3 Department of Evolutionary and Experimental
Biology, University of Bologna, via F. Selmi 3,
I-40126
Bologna, Italy
The
distribution and abundance of carbonate-eroding microorganisms was investigated
along a
bathymetrical
gradient in waters of the Red Sea adjacent to Eilat, Israel. Experimental
carbonate
substrates
were deployed in depths of 0m, 6m, 15m and 30m, placed in clear and shaded
habitats for
a
period of 6 months. The community of microendoliths that had colonised the
substrates by then was
taxonomically
analysed. It shows a large correspondence with microendolithic communities from
Atlantic,
Caribbean and Pacific marine environments. The same array of species of
Cyanobacteria,
Chlorophyta,
Rhodophyta and Fungi was found to colonise comparable water-depths in Eilat.
This
study
concludes and summarizes a series of investigations on the impact of
microendoliths in marine
tropical
environments..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
36
IS
IT CURTAINS FOR CORAL REEFS IN THE SOUTHERN ARABIAN GULF?
J.
David George, David M. John
The
Natural History Museum
Cromwell
Road, London SW7 5BD, UK
Most
coral reefs in the southern Arabian Gulf are shallower than 10m and normally
are subject to
very
high summer seawater temperatures and year-round high salinities. In fact the
southern Gulf
has
the highest global summer seawater temperatures and the corals (or their
symbiotic
zooxanthellae)
are probably surviving near their upper physiological tolerance limits. These
reefs are
composed
primarily of the branching coral Acropora or of colonies of
mound-forming Porites. In
many
cases inshore reefs fringe the outer edge of shallow-water limestone platforms
that often extend
seaward
for many kilometres from a landmass, be it the mainland or an island. Offshore
patch reefs
form
a cap on a base of limestone, sandstone or fasht.
In
the summer through to the autumn of 1996 we observed that approximately 98% of
the Acropora
bleached
and subsequently died along the coast of Abu Dhabi and adjacent Dubai, although
the non-branching
corals
were largely unaffected. The death of the Acropora coincided precisely
with a
prolonged
period of higher-than-normal seawater temperatures. Later a similar mass
mortality of
Acropora
was reported by divers in Qatar and Bahrain where summer seawater
temperatures were
also
abnormally high for an extended period. An even more prolonged incidence of
abnormally high
seawater
temperatures occurred in the summer of 1998 and this resulted in the majority
of the
remaining
reef- forming corals in Abu Dhabi being severely affected; an estimated 50-80%
mortality
being
observed in the western and central regions of the Emirate.
A
consequence of the coral death has been a dramatic increase in cover of the
once relatively
inconspicuous
non- geniculate red coralline algae and mat or turf forms that have now
colonise the
dead
coral skeletons. The most abundant and conspicuous coralline alga overgrowing
the dead coral
(Lithophyllum
kotschyanum) is slowing the disintegration of the branching Acropora skeletons
in
particular,
by providing them with a coating of limestone. Nevertheless, the relentless
activities of
boring
clionid sponges and bivalve molluscs along with the grazing of greatly
increased numbers of
the
sea urchin Echinometra mathaei are gradually reducing the Acropora thickets
to rubble and in
some
places are significantly reducing the volume of the dead Porites mounds.
Some
coral regeneration and recruitment has taken place since the 1998 incident.
However, the
gradual
increase in average seawater temperatures in the region over the last 30 years
and the more
frequent
occurrence of prolonged higher-than-normal summer seawater temperatures leads
us to
believe
that the future of coral reefs in the southern Arabian Gulf is bleak. We
speculate that in the
next
few decades the once coral-dominated reefs will become transformed into ones composed
essentially
of coralline and turf- forming algae with shallower areas becoming overgrown
during the
cooler
winter months by dense forests dominated by fleshy brown macroalgae..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
37
HIGHER
LATITUDE CORAL REEF COMMUNITIES OFF DENSELY POPULATED
SOUTHEAST
FLORIDA, USA
David
S. Gilliam 1 , Susan L. Thornton 1 , Louis E. Fisher 2 , and Kenneth Banks 2
1 National Coral Reef Institute (NCRI)
Nova
Southeastern University Oceanographic Center (NSU OC)
8000
North Ocean Drive
Dania
Beach, Florida 33004 USA
2 Broward County Department of Planning and
Environmental Protection (BC DPEP)
218
S.W. 1 st Ave
Fort
Lauderdale, Florida 33301 USA
Significant
coral reef community development along the eastern shelf of the United States
is often
described
as stopping north of the Florida Keys (Latitude 25°
30’N). Nevertheless, a coral reef
ecosystem
continues northward (160+ km) of the Keys, through Miami- Dade, Broward, and
into
Palm
Beach Counties, Florida (Latitude 27° N).
The coral communities associated with this high
latitude
reef system have approximately 30 species of stony corals with a coverage of
2-3% and
includes
a diverse assemblage of soft corals, sponges and fishes. NSU OC and NCRI are
working
with
local resource mangers (BC DPEP) on a reef monitoring program that collects
information on
stony
(species richness, cover, mortality and disease) and soft corals (abundance),
sponges
(abundance),
fishes (abundance and species) and sedimentation (rate and grain size). The
reef system
of
Southeast Florida is typically described as having three reef ridges/terraces
that run parallel to
shore
in sequentially deeper water. The general depth of the crest of the inshore (or
first) reef is 5 m;
the
middle (or second) reef is 10 m; and the offshore (or third) reef is 17 m.
Water temperatures were
measured
in 2000 and 2001 and ranged from a minimum of 19.5 °C in the winter months
(December
–
February) to a maximum of 31.0 °C in the summer months (July – September). This
reef system
occurs
near a highly urbanized area (the population of Broward County exceeds 1.6
million people,
two
inlets discharge offshore, and the reefs are within 3 km of the coast). As
such, commercial and
recreational
fishing and diving, major shipping ports, ship groundings and dredging
activities
influence
the system. The unique features of this reef system, and its proximity and
value to the urban
community
of Southeast Florida, demand continued monitoring and increased investigation
into the
processes
that affect it..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
38
POPULATION
DYNAMICS IN THE MEDITERRANEAN SOLITARY CORAL
BALANOPHYLLIA
EUROPAEA (SCLERACTINIA, DENDROPHYLLIIDAE)
Goffredo
S., Mattioli G., Zaccanti F.
Department
of Evolutionary and Experimental Biology,
University
of Bologna, via F. Selmi 3, I-40126 Bologna, Italy
Studies
performed to date on the population dynamics in scleractinian corals refer,
mainly, to tropical
species.
Although scleractinian corals are common to the Mediterranean benthic fauna,
data
concerning
demography in species of this area are rare. Balanophyllia europaea is a
solitary
zooxanthellate
coral living off the rocky Mediterranean coast at depths ranging from 0 to 50m.
Its
reproductive
biology is characterized by simultaneous hermaphroditism and brooding. We
studied
individual
growth rates and the structure of the population living off the coast of
Leghorn at Calafuria
(eastern
Ligurian Sea). B. europaea individuals living in this area were found at
depths ranging from
1 to
13 meters with an average population density of 16 individuals m -2 (SE = 3); maximum density
was
reached at 6 m depth with a peak of 113 individuals m -2 (SE = 33). At this depth, we studied the
growth
patterns in 62 individuals for a two-year period. The linear growth rate was
found to be
inversely
correlated to the individual size of the polyps. As the polyps length increased
(= major
diameter
of the polyp’s oral disc) growth rate decreased. This correlation held true to
a maximum
length
of 21 mm at which point growth rate became practically zero. Von Bertalanffy’s
theoretical
growth
function obtained on the basis of measurements taken in the field was confirmed
by counting
the
annual skeletal growth bands on specimens scanned using CT (computed
tomography). From
growth
data, we estimated the ages of 1814 individuals. The resulting survival curve
showed that
average
age of individuals in this population was 4 years with a maximum longevity of
20 years.
Compared
to populations of B. elegans living off the north American Pacific
coast, the other
congeneric
species for which data on population dynamics and reproductive bio logy are
known,
individuals
of B. europaea achieve greater lengths and longevity (about two and
three times,
respectively)
and a lower population density (about 35 times lower). The difference in
existing
demographic
features pertaining to the two species summed to the actual differences in
their ecology
(B.
europaea is zooxanthellate and B. elegans is azooxanthellate) and in
their reproductive biology
(hermaphroditism
in B. europaea and gonochorism in B. elegans; and an elevated
fecundity, short
incubation
period with small planktonic planulae in B. europaea and the exact
opposite in B. elegans)
point
to the fact that in the two species exist two opposite life strategies..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
39
POPULATION
STRUCTURE OF DEEP-SEA CORAL LOPHELIA PERTUSA IN THE
NORTH
EAST ATLANTIC SEEN THROUGH MICROSATELLITES
Marie
Le Goff-Vitry, Alex Rogers
School
of Ocean and Earth Science
University
of Southampton
Southampton
Oceanography Centre
European
Way
Southampton
SO14 3ZH, UK
The
azooxanthellate scleractinian coral, Lophelia pertusa, is distributed
globally on continental
slopes,
mid-oceanic ridges and in fjords. In the North East Atlantic, it is the main
reef constructing
species
in the upper bathyal zone on continental margins and offshore banks. These
cold, deep coral
reefs
are associated with a highly diverse animal community. These ecosystems are
still poorly
understood,
but under increasing threat from the expanding human activities beyond the
continental
shelf,
and notably bottom-trawling. Recommendations are needed to monitor Europe’s
deep-water
coral
margin. In order to understand the capacities of the coral to withstand human
impacts and to
recover
from them subsequently, data concerning the population genetic variability,
mode of
reproduction
and dispersal must be gathered.
Efficient
molecular tools can be used to address such population genetic structure
issues.
Microsatellites
are non-coding DNA sequences constituted by short tandemly repeated motifs
dispersed
throughout the genome. Because they are inherited in a Mendelian manner,
selectively
neutral
and very variable among individuals, they can be used as high-resolution
molecular markers
for
investigating population substructure. For this purpose, a genomic library
enriched for
microsatellites
was constituted for Lophelia pertusa and ten specific microsatellite
markers were
developed
to screen a set of individuals sampled at different sites distributed along the
European
margin.
Comparison with a model population, described by Hardy-Weinberg principle as
panmictic
and
under no selection force, showed a marked departure from this state of
equilibrium. This reveals
the
substantial contribution of asexual reproduction to the maintenance of the
population and
suggests
the existence of local, isolated sub-populations in the considered geographic
area.
In
order to check these preliminary hypotheses, a more detailed analysis,
involving inter-site
comparisons
and using bigger sample sizes, was performed. As a result, North East Atlantic Lophelia
population
appeared highly structured, suggesting a very low gene flow between areas. The
relative
contribution
of sexual versus asexual reproduction to the maintenance of populations showed
considerable
variation among sites. These results have strong implications for the recovery
of the
reefs
following human impact; recolonisation of a disturbed area is likely to be
slow. Moreover, the
observed
heterogeneous distribution of the genetic diversity across the margin means
that the loss of
a
specific population can affect the overall genetic diversity for the species
across the entire area.
Further
statistical analysis is to be performed on the existing data and the
microsatellite approach will
be
combined with other molecular methods to check the validity of these
conclusions and to get a
broader
view of the genetic history of Lophelia populations along the European
margin..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
40
GLOBAL
PROTECTION OF CORAL REEFS
Ed
Green, Mark Spalding, Corinna Ravillious, Jamie Oliver
UNEP-World
Conservation Monitoring Centre,
219
Huntingdon Road, Cambridge, CB3 0DL, UK
With
increasing global environmental degradation calls for ‘protection targets’ are
being made more
frequently.
For example the 4 th World Congress on
National Parks and Protected Areas in 1993
advised
that 10% of each biome receive protection. Likewise, the 1 st Symposium on Marine
Conservation
Biology in 1997 called for an increase in the number and effectiveness of MPAs
so that
20%
of all nations’ Exclusive Economic Zones and the High Seas be protected by the
year 2020. One
problem
with such recommendations for marine ecosystems is that the data have not been
available
to
calculate the quantity protected and to estimate when targets for protection
have been reached.
Increases
in the accuracy and resolution of global coral reef maps have recently been
possible
through
the International Coral Reef Action Network (ICRAN) and the research behind the
World
Atlas
of Coral Reefs. Considerable improvement to global information on those marine
protected
areas
(MPAs) which contain coral reefs has been made through the same initiatives.
Consequently
our
understanding of the global distribution of coral reefs and the efforts being
made to manage them
through
the use of protected areas has never been better. New estimates of global coral
reef area have
been
produced and the inventory of data on coral reef MPAs – location, size,
boundaries - is more
complete.
The
results of ongoing analysis which has combined coral reef maps and MPA data
will be presented.
The
amount of coral reef presently being managed within MPAs will be estimated, and
variations by
region
and management regime will be calculated. A comparison will be made between
protection
offered
by nationally and internationally designated MPAs. The utility of global
‘protection targets’
for
coral reefs will be discussed in relation to management effectiveness, which
for most MPAs
remains
unknown..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
41
CORAL
REPRODUCTIVE SYNCHRONY ON SINGAPORE’S REEFS
Guest
JR, Baird AH, Goh BPL, Chou LM
Department
of Biological Sciences
National
University of Singapore
Blk
S2 14 Science Drive 4
Singapore
117543
There
are very few reports of multispecific, synchronous coral spawning from reefs in
Southeast
Asia.
It has been suggested that on low latitude reefs the ‘mass spawning’ phenomenon
may be
absent,
or significantly reduced. Singapore is a small, industrialized and heavily
populated Southeast
Asian
country, located approximately 1° north
of the equator. Despite there being high levels of
sedimentation
and turbidity in the coastal waters, reasonably diverse coral communities can
be found
around
some of the islands to the south of the mainland. Histological analysis of
selected coral
species
sampled between September 1999 and October 2000 showed the presence of mature
gametes
at
two times of the year (Feb – April and Sept – Nov). Sampling of Acropora species
to determine
the
extent of reproductive synchrony within the population was conducted at
Singapore’s southern
most
reef (Raffles Lighthouse, 1° 10’N 103° 45’E). Sampling was carried out by
breaking off a
branch
from the middle of the colony and noting the presence or absence of mature eggs
(which are
pigmented)
or immature eggs (which are white). In March 2002, a few days prior to the full
moon,
48.5%
of the Acropora population had mature eggs, 10% had immature eggs and
the rest had none (n
=
113). In April 2002, 23% of the Acropora population contained mature
eggs (n = 74), and in May
2002
none of the sampled colonies contained mature eggs (n = 79). On the 3 rd , 4 th and
5 th nights after
the
March 2002 full moon, synchronous spawning of corals was observed on the reef
at Raffles
Lighthouse.
At least 18 different coral species from 10 genera and 5 families (Acroporidae,
Faviidae,
Merulinidae,
Oculinidae and Pectiniidae) were observed releasing gametes over the three nights.
This
observation
demonstrates that mass coral spawning can indeed be a characteristic of
equatorial reefs.
The
possible environmental cues involved in synchronizing corals on low latitude
reefs will be
discussed..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
42
DEEP
CORAL REEFS, BOTH SIDES OF THE ATLANTIC: FISHERIES, EVOLUTION
AND
CLIMATE CHANGE ASPECTS
Jason
Hall-Spencer 1 , Michael J. Risk 2
1 University Marine Biological Station
Millport,
Isle of Cumbrae, KA28 0EG, UK
2 School of Geography and Geology,
McMaster
Univ., Hamilton ON Canada L8S 4M1
The
continental shelves of both Europe and North America support thriving
deep-water “reefs.” Their
distribution
is puzzling: northern Europe and the southern USA have Lophelia reefs,
whereas Canada
has
gorgonian forests. Hovland has suggested that Lophelia reefs are
nourished from below, via
hydrocarbon
seepage. All reefs, deep and shallow, may therefore be classified as to their
relative
dependence
on energy sources:
-sunlight:via
zooxanthellae- most modern offshore coral reefs.
-seepage:
via bacterial remobilization-northern Europe, Western Australia, Louisiana.
-exogenous:
zooplankton; POM and DOM from terrestrial sources- inshore reefs, Paleozoic
rugosan
reefs.
Deepwater
reefs are under at least as much stress as shallow reefs, with reports ranging
from
widespread
damage to complete extirpation (usually from trawling). They need protecting,
because of
their
immense value in fisheries, the priceless climate archive in the coral
skeletons, and (last but not
least)
as possible sources of gametes to recolonise and re-establish reefs on the
shelves if we ever
clean
up our act.
Both
types of reef-Lophelia bioherms and gorgonian forests-represent habitat
complexity, and hence
are
deep-water FAD’s. The Lophelia reefs are sometimes large accumulations
of skeletal debris, with
a
reticulate surface coral veneer-these seem to attract monkfish and demersal
roundfish (esp.
grenadiers).
The Canadian coral forests, B. T. (Before Trawling) formed extensive thickets,
with
individual
corals to 10 m in height. These were select areas for halibut, cod and redfish.
The decrease
in
fish catches concomitant with habitat destruction has caused erection of
deep-water MPA’s in
Norway
and off Tasmania. Canada has done nothing.
Evolution
of the deep coral fauna is a mystery. Atlantic zonation may be temperature
dependant, but
temperature
alone does not explain the disjunct distribution of Lophelia.
Reproductive habits of
individual
corals will be important. Some “deep” species can range from 4 km to 4 m in
depth, and
some
exist in zooxanthellate and azooxanthellate forms. If indeed dire predictions
come true, and we
lose
all our shallow reefs in the next few decades, the only hope of natural
recolonisation of the
shallow
shelves will be the deep survivors.
Verification
of some of these predictions will come from the corals themselves. Deep-water
corals
are
far better climate recorders than are reef corals: they live at all depths in
all oceans, and have
equivalent
lifespans (several centuries). They are reliable (and KIE-free) temperature
recorders, with
monthly
precision. Our research group has just retrieved a 250-year record of the North
Atlantic
Oscillation,
which drives the location of the Gulf Stream..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September, 2002
43
ECOLOGY,
SEDIMENTOLOGY AND HYDRODYNAMICS OF A REEF FLAT AND
CORAL
CAY BEACH, WARRABER ISLAND, TORRES STRAIT.
Deirdre
E. Hart
School
of Geography and Oceanography,
University
of New South Wales ADFA,
Canberra,
ACT 2600, Australia
dhart@adfa.edu.au
This
paper reports on a PhD project concerning the nature of contemporary
ecological, sediment and
hydrodynamic
interactions within a reef flat system, the relationship between different reef
flat
environments
and the adjacent island beach and, in particular, the present sediment sources
of the
beach.
Fieldwork
for the investigation was conducted on Warraber, a small, oval-shaped coral cay
and large
platform
reef system with a combined total area of 11 km 2
, in the central Torres Strait, Australia. An
array
of beach profiles and reef flat transects were surveyed, beach and reef flat
sediments were
sampled
and an ecological census was conducted on the reef flat. Wave, current and tide
measuring
instruments
were used to examine water flows across the reef flat and longshore and
cross-shore
flows
around the island margin. Twelve sets of four-directional sediment traps were
employed in
conjunction
with the hydrodynamic instruments.
Initial
analyses indicate that water flows across the reef flat were dominated by
topographically
modified
tidal flow. Reef flat exposure and submergence reflected the interaction of
platform
morphology
with water levels and exerted strong controls on the energy conditions, and the
ecological
and sedimentology characteristics of each reef flat zone. Eight distinct
ecological-sediment
reef
flat zones were identified. These include muddy-sandflats with brown algae,
large
areas
of sandflat covered with gastropods, broad bands of dense branching corals and
a diverse,
encrusted,
coral-algal rim. The size and composition of insitu reef flat sediments
was diverse,
variable
and related to the local carbonate producers. The beach sediments, in contrast,
were less
variable,
being dominated by gastropods and, to a lesser extent, coral and calcareous
algae fragments.
The
present supply of beach sediments originated from a limited area of the reef
flat, including
elevated
sandflats to the east and dense branching coral zones to the west of the
island. Sediment
transport
rates around the island were very variable and dominated by longshore movement.
Small
seasona
l changes were observed in the island beaches whilst significant seasonal
differences were
observed
in reef flat sediment deposits.
Initial
findings indicate that important factors controlling the variability of gross
sediment transport
rates
across the Warraber reef flat were exposure and submergence, the strength of
tidal currents and
the
availability of insitu material. The potential for material from each
reef flat zone to contribute to
beach
deposits was, in part, a function of proximity to the island. However, this
potential was also
strongly
controlled by more complex interactions between the tides, reef flat water
levels and
topography,
and by the availability of appropriately sized sediment. Further analyses will
aim to (1)
determine
the rate of sediment production in the various zones of the reef flat; (2)
refine the sediment
pathways
across the reef flat and onto the island beach; and (3) tease out the relative
roles of tides,
topography,
hydrodynamic patterns and distance as determinants of reef flat and beach
sediment
sources
and sinks..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
44
IN
VIVO MONITORING OF A CORAL-BACTERIAL ASSOCIATION
Marshall
L. Hayes*, Mark J. Vignola
Duke
University Marine Laboratory
135
Duke Marine Lab Rd.
Beaufort,
NC 28516 USA
mhayes@duke.edu
*
present address :
Observatoire
Océanologique Européen Centre Scientifique de Monaco
Av.
Saint Martin
Monte
Carlo 98000 Monaco
Research
interest in the association between corals and microbes has increased
dramatically in recent
years,
particularly in response to evidence of disease emergence in the world’s coral
reef ecosystems.
Here,
we explore the potential of using bacteria labelled with fluorescent proteins
in experimental
studies
of bacterial interactions with the coral mucosal surface and the underlying
epithelium. Three
fluorescent-protein
expression vectors (p519gfp, p519cfp and p519rfp) have been successfully
transferred
via tri-parental conjugation to a bacterial strain implicated in the white
plague type II
disease
in scleractinians. The genes encoded on these plasmid vectors differ in the
spectral signal of
their
fluorescent products, thus providing flexibility when dealing with problems of
coral
autofluorescence.
In our studies, the temperate stony coral, Oculina arbuscula, serves as
the host
organism
for closed-system inoculation experiments. We show that fluorescent-protein expression
does
not adversely affect bacterial survival and activity and that maintenance of
the plasmid vector
remains
stable even in the absence of the counterselectable marker. Epifluorescence and
confocal
laser
scanning microscopy are used to visualize the presence of pathogenic bacterial
cells in
association
with coral cells. In principal, this approach may promise a rapid and
non-destructive
method
to track bacterial adhesion, colonization, and perhaps even invasion of coral
tissue in situ..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
45
GLOBAL
CORAL REEF HEALTH: FIVE YEARS OF STEADY DECLINE
Gregor
Hodgson, Jennifer Liebeler, Georg Heiss
Reef
Check, Institute of the Environment
1362
Hershey Hall Box 951496
University
of California at Los Angeles
Los
Angeles CA 90095 – 1496 USA
gregorh@ucla.edu
During
the five-years from 1997 to 2001, 1081 reefs in all oceans were monitored using
the Reef
Check
protocol. The results of the 1997 survey were the first to demonstrate that
there was a global
coral
reef crisis due to overfishing. Subsequent results have shown a continuing
decline in many of
the
25 Reef Check indicators of reef health such as butterflyfish, grunts, grouper,
parrotfish and sea
cucumber.
Several indicators such as lobster and Tridacna clams are missing from most
reefs. Over
the
five-year period, the percentage of living hard coral has been consistently
higher in the Pacific
than
the Atlantic. Recently killed coral was four times higher in the Pacific than
the Atlantic in 1998
following
the global bleaching event, but is now equal in the two regions. Since 53% of
the
monitored
reefs have some form of legal protection, and 90% are in developing countries,
enforcement
appears to be a continuing challenge. In these protected sites, diver damage
was ranked
as a
major perceived impact in both oceans, with fishing and sewage also important.
The theory that
participation
in Reef Check wo uld lead to increased stewardship has been demonstrated by
teams
helping
to establish and maintain successful marine parks in Africa, Asia and the
Caribbean..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
46
IOC/UNESCO-WB
TARGETED WORKING GROUP ON CORAL BLEACHING
Ove
Hoegh-Guldberg
Centre
for Marine Studies,
University
of Queensland, St Lucia,
QLD
4072, Australia
The
growing link between mass coral bleaching and global climate change is driving
an urgent need
for
information on how changes in global sea temperature, the major factor driving
coral bleaching
events
across the globe, will affect the viability of the world’s coral reef
ecosystems. The potential
scale
of this ecological change is of major concern in both developing and developed
nations. In
response
to this concern, UNESCO’s Intergovernmental Oceanographic Commission (IOC)
established
an expert Study Group focused on Coral Bleaching and Related Indicators of
Coral Reef
Health
in 2000. The aim of this group was to integrate and develop research that will
allow more
reliable
predictions of climate impacts and the development of better bioindicator tools
for managers.
At
the first meeting held 9-11 April 2001 at IOC, Paris wide ranging discussions
between the group
and
the representative of a related World Bank project led to the fusion of the
group to become the
IOC/UNESCO-World
Bank Targeted Working Group on Coral Bleaching. The immediate goals of
the
reconstituted group are to identify critical gaps in our knowledge of the
molecular to ecological
processes
involved in mass coral bleaching, and to develop specific, testable hypotheses
that will be
the
focus of targeted investigations in four key ocean areas. The ocean areas
selected are located in
East
Africa (Zanzibar), the Philippines (Bolinao), Eastern Australia (southern GBR)
and Mexico
(Puerto
Morelos). In addition to targeted research activities, the work plan is aiming
to involve local
scientists
and students in a series of activities that will range from training workshops
to collaborative
experiments.
The project development is partially funded by a World Bank Block B grant, in
addition
to funding from host institutions like the University of Queensland and is
designed to
explore
how a full work plan can be implemented to pursue a complex set of questions
over 5 years.
A
2002 workshop on Heron Island was the first step in testing the concept of
targeted research within
one
of the four ocean areas. A large group (32 scientists and 18 postgraduate
students) collaborated
on
testing hypotheses developed during the April 2001 discussions in Paris. The
coincidence of a
major
bleaching event across the Great Barrier Reef during the workshop led to some
unusual
opportunities
for the targeted working group to pursue questions associated with a “natural”
bleaching
event. Among the highlights of this successful workshop were a major audit of
symbiotic
dinoflagellate
strains, the discovery of new coral diseases for the GBR region, new insights
into the
role
of cell suicide and apoptosis in bleaching and the important role of clonal
variability in coral
stress
tolerance..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
47
THE
RELATION OF BLEACHING SUSCEPTIBILITY TO ZOOPLANKTON FEEDING
BEHAVIOUR
IN THE CORAL GENUS MONTASTRAEA
C.
Hueerkamp*, E. Weil**
*Center
for Tropical Marine Ecology ZMT, Bremen, Germany.
chrhueerkamp@hotmail.com
**Dep.
Marine Sciences, U. of Puerto Rico. Box 908, Lajas PR 00667 USA
Reef-building
corals can complement their nutrition needs in many different ways. The two
most
important
are translocation of photosynthetic products from the endosymbiotic
zooxanthellae and
capture
of zooplankton by the tentacles of the polyps. Corals bleach under temperature
stress
conditions;
the density of their symbionts declines and the corals lose not only their
colour but also
their
main nutritional source. Two massive species of the genus Montastraea from
the Caribbean
coast
of Puerto Rico were selected to conduct feeding experiments under temperature
stress; M.
faveolata
with relatively small polyps and M. cavernosa with larger polyps.
Two distinct morphs of
M.
cavernosa were separated, M1 has very large polyps, and M2 has
significantly smaller polyps.
However,
both M1 and M2 morphs have significantly larger polyps than M. faveolata.
Experiments
were
designed to compare the role of feeding by tentacle capture under temperature
stress conditions
and a
control. Non-bleached coral pieces were collected from the field and exposed to
elevated water
temperature
in an aquarium to compare the effects of enhanced zooplankton feeding (with
nauplii of
Artemia
salina) on bleaching induction. Pieces of the same colony were kept in an
aquarium with
normal
temperature. Zooxanthellae counts were made in tissue samples to quantify the
extend of
bleaching.
The amount of ingested Artemia was determined to assess feeding
activity, and the
nitrogen
content was also measured. M. cavernosa M1 exhibited the least bleaching
susceptibility
whereas
M. faveolata (with smaller polyps) showed a fastest decrease in the
density of zooxanthellae.
The
most resistant species was M. cavernosa with higher zooplankton feeding
rates at higher
temperatures
compared to ambient temperature conditions. The less tolerant coral was M.
faveolata
which
showed the same trend of increasing feeding rates at higher temperatures but,
this trend was
less
consistent over time.
The
results suggest that zooplankton feeding can partly substitute the loss of the
zooxanthellae up to
a
certain degree and duration of bleaching. It is proposed that corals with
bigger polyps and larger
tentacles,
like M. cavernosa, can increase zooplankton feeding during bleaching for
a certain time
period
and therefore, can better compensate the decline of zooxanthellae and the
resulting nutritional
deficit
during sea warming episodes. This may be an explanation of why M.cavernosa bleaches,
when
it does, later during intensive bleaching events..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
48
DEFINING
SUCCESS IN MARINE PROTECTED AREAS
Hutchinson,
D.J., Brown, K., Côté, I.M.
University
of East Anglia
Schools
of Biological Sciences and Development Studies UEA Norwich NR4 7TJ, UK
Marine
protected areas (MPAs) are the primary form of protection in the marine coastal
zone and are
being
used by many as a spearhead for marine conservation. However, there is much
debate with
regard
to their effectiveness. This paper addresses a key question in this debate,
namely, “What
defines
MPA success?”, and in doing so will highlight areas for potential research and
discussion.
Reef
communities are both biologically and socially dynamic systems which form
complex
interactions.
This complexity is often not fully recognised, and hence leads to complication
in the
operation
of many MPAs. Through a review of the objectives and outcomes of a large number
of
Caribbean
MPAs, we show that an understanding of context is essential for effective
analysis and
hence
recommendation. This is further supported by a detailed examination of the
social and natural
systems
of three Eastern Caribbean MPAs; Barbados, Bonaire and St. Lucia. We show that
the use
of a
priori performance criteria in the evaluation of MPA success requires
careful consideration
before
implementation. This is a highly relevant exercise considering the increasing
number of
attempts
from both the social and natural sciences to assess MPA success using such
methods. The
use
of most performance criteria implies an inherent assumption that the system
under study should
match
a predefined template. However, the objectives stated on paper during MPA
establishment
may
not often match real outcomes due to the complex nature of
institution-ecosystem interactions.
We
suggest that defining the success of reef-encompassing MPAs depends very much
on the
responsible
and intelligent use of criteria. A precursor to their implementation, which
will lead to a
more
realistic appraisal, is to take into account constantly shifting social
intentions and the ability of
the
whole system to respond to change. To accurately define success will depend on
a thorough
understanding
of the natural and social environment, which can only come about through a
balanced
interdisciplinary
approach..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
49
THE
EVOLUTION OF CORAL-ZOOXANTHELLA SYMBIOSIS IN TURBID HABITATS
AND
IMPLICATIONS FOR RESPONSE TO GLOBAL CHANGE
J.
Rebecca Jacobs, Donald C. Potts
Ecology
and Evolutionary Biology,
University
of California,
Santa
Cruz CA 95064 USA
Appreciation
for the long-term consequences of global change on coral reefs and the
coral-zooxanthella
symbiosis
may be constrained by a late Holocene perspective that tends to limit
thinking
about scleractinian ecology and evolution to predominantly oceanic settings,
without
considering
either the conditions under which scleractinians and coral- zooxanthella
symbiosis
evolved
during the Triassic or those experienced since then. We propose that a variety
of turbid,
inshore
habitats have been continuously available to scleractinians through geological
time, that these
have
provided both ecological and evolutionary continuity, and that they have served
as both refugia
for
scleractinian corals during non-reefal periods and as primary habitat. We
propose such turbid,
inshore
environments have influenced the evolution of scleractinian corals and the
evolution of coral-zooxanthella
symbiosis.
Since these coastal habitats are now strongly influenced by human
activities,
it is important to consider the consequences for long-term coral survival in
these habitats,
especially
since anthropogenic activities on land are degrading coastal ecosystems and may
be
increasing
the distribution of turbid habitats. With the ever- increasing stresses on
coral reef
ecosystems,
consideration of how corals respond, and of possible advantages that may be
conferred
by
the coral- zooxanthella symbiosis in inshore environments may enhance
understanding of the
capacity
of scleractinians to adapt to global change..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
50
PREDICTING
THE LONG TERM EFFECTS OF CORAL BLEACHING AND CLIMATE
CHANGE
ON THE STRUCTURE OF CORAL COMMUNITIES
1 Craig R Johnson, 1 Piers K Dunstan, 2 Ove Hoegh-Guldberg
1 School of Zoology, and Tasmanian Aquaculture
and Fisheries Institute, University of Tasmania,
GPO
Box 252-05, Hobart, Tasmania, Australia 7001 2 Centre for Marine Studies, University of Queensland,
Queensland, Australia 4072
Because
coral species show differential susceptibility to bleaching, and coral
communities are so
variable,
predicting the effects of coral bleaching on benthic coral reef communities
requires
developing
predictive models of particular reef locations. We developed a spatial
(cellular automaton)
model
of shallow benthic communities on two midshelf reefs on the Great Barrier Reef
(GBR). We
considered
only corals, turf algae, and non-geniculate coralline algae since these are the
principal space
occupants.
The dynamics of the model is driven entirely by local processes, namely,
outcomes of
neighbour-specific
interactions, neighbour-specific growth rates, and recruitment and mortality rates.
These
parameters were estimated from observations in 140 fixed quadrats photographed
every 6
months
over 3 years.
Despite
that the potential state-space of predicted communities is very large, actual
community
structure
of the real reefs in terms of the absolute cover of 12 life- form
(physiognomic) categories was
predicted
accurately as an emergent property of the models. Having derived a model that
predicts
community
structure of the real reefs, we simulated several scenarios of coral mortality
as a result of
bleaching
and climate change. In all simulations, bleaching events occur at intervals of
10 years over a
100
year period, and there is annual recruitment of all 12 life-form groups. The
effect of bleaching
events
on coral mortality was as observed in the 1998 bleaching event on the GBR when
maximum
water
temperatures rose to 31.5 °C.
For
all scenarios, the model predicts significant degradation of reefs in <100
years. With no further
warming
and a single bleaching event each decade, cover of turf and coralline algae
increases to ~75%
while
coral cover declines to ~25% in 60 years. If ocean warming continues at 0.1 °C
per decade, and
assuming
100% mortality of corals at 32.5 °C (based on recent observations of thermal
tolerance
thresholds
over the latitudinal range of the GBR), then coral cover declines steadily to
<15% after 100
years.
Control reefs without bleaching support 60% coralline and turf algal cover, and
40% coral cover.
Notably,
different guilds of corals respond differentially to bleaching. Some groups
decline gradually
with
successive bleaching events (e.g. most Acroporidae), others show little effect
for several decades
before
declining suddenly (e.g. Faviidae), while groups little affected directly by
bleaching (e.g.
massive
Porites) can increase in abundance under some bleaching scenarios. The
abundance of
thermally
‘tolerant’ genotypes may persist at relatively constant levels for several
decades of bleaching
before
suffering sudden reductions in cover.
Because
this type of spatial model can readily integrate processes from the molecular
to community
level,
it is a strong candidate for further refinements of predictions of the effect
of climate change on
the
community structure and dynamics of coral reefs..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
51
MONITORING
CHANGES IN THE FULLY PROTECTED ZONES OF THE FLORIDA KEYS
NATIONAL
MARINE SANCTUARY
Brian
D. Keller
Florida
Keys National Marine Sanctuary
P.O.
Box 500368
Marathon,
FL 33050, USA
brian.keller@noaa.gov
The
Florida Keys National Marine Sanctuary is a 9,850-km 2 marine protected area managed by the
U.S.
National Oceanic and Atmospheric Administration and the State of Florida. A
comprehensive
management
plan was implemented in 1997 to protect and conserve marine resources of the
Florida
Keys.
One aspect of the management plan is the creation of a network of 23 fully
protected zones
(marine
reserves); the Tortugas Ecological Reserve was implemented in 2001 as the 24 th fully
protected
zone, the largest marine reserve in U.S. waters (518 km 2 ). An ongoing monitoring program
is
designed to determine effects of “no-take” protection on heavily exploited
fishes and invertebrates,
benthic
communities, and human activities. Data on the abundance and size of reef fish,
spiny
lobster,
and queen conch; algal cover; and coral cover, diversity, and recruitment are
collected from
fully
protected zones and adjacent reference sites. Socioeconomic analyses are also
being conducted.
Preliminary
reports indicate increases within the fully protected zones in the number and
size of
heavily
exploited species such as spiny lobster and certain reef fishes. Slower-growing
benthic
species
such as corals and sponges have not shown significant changes within fully
protected zones,
possibly
because the zoning plan was implemented less than five years ago..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
52
UPWELLING
REFUGIA IN TIMES OF ENVIRONMENTAL STRESS
Rebecca
Klaus, John Turner 1
Ecology
& Epidemiology Group, Department of Biological Sciences,
University
of Warwick, CV4 7AL, UK
1 School of Ocean Sciences, University of Wales,
Bangor,
Menai Bridge, Anglesey, LL59 5EY, UK
Efforts
to map and assess the global extent of coral reefs at risk have ignored the
significant extent of
non-reefal
coral communities. Although lacking the classical geomorphological structures
of a ‘true’
reef,
these communities can harbour diverse and unique assemblages and confer many of
the same
benefits.
In addition, non-reefal coral communities typically occur in marginal
locations, subject to
unusual
physical regimes, which may confer additional resilience during times of
environmental
stress.
Glynn proposed the theory that upwelling areas could act as refugia for species
diversity
during
mass coral bleaching events in the Pacific. Mass coral bleaching events have
been linked to
both
prolonged exposure to solar radiation and elevated sea temperatures associated
with large-scale
disturbances
in ocean-atmospheric dynamics. The theory that zooxanthellate coral communities
in
areas
subject to cool upwelled water could act as potential species refugia is
investigated with respect
to
the severe 1997-1998 Indian Ocean wide coral bleaching event, with particular
reference to the
islands
of Socotra (Republic of Yemen), including Samha and Darsa, Abd Al Kuri,
Sabunya, and Kal
Farun,
located in the extreme northwest Indian Ocean (12-13 o N, 52-55 o E). The islands
of Socotra
are
exposed to a wind-driven upwelling system, known as the Great Whirl, resulting
from the
northwards
passageof the Somalia current along the east African coast during the boreal
summer
months.
Recent surveys have found that these islands support a diverse (250+ species)
scleractinian
coral
fauna. Coral dominated communities found along the northern shores of these
islands naturally
intergrade
with mixed macroalgal and coral communities on expose southern shores.
Bleaching
induced
mortality of coral communities around the islands of Socotra was spatially
variable and
ranged
from negligible around the outer islands to severe (>90% mortality) along
northern shores.
The
spatial distribution of bleaching induced mortality around the islands was
compared with high
resolution
(9km daily AVHRR Pathfinder) sea surface temperature (SST) to determine whether
upwelling
had influenced bleaching outcomes..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
53
LITHOPHAGA
(BIVALVIA: MYTILIDAE), INCLUDING A NEW SPECIES, BORING IN
MUSHROOM
CORALS (SCLERACTINIA: FUNGIIDAE) AT SOUTH SULAWESI,
INDONESIA
Karl
Kleemann 1 , Bert W. Hoeksma 2
1 Institute for Palaeontology, University of
Vienna, Althanstr. 14, A-1090 Vienna, Austria 2 National Museum of Natural History / Naturalis,
P.O.
Box 9517, 2300 RA Leiden, The Netherlands
Bivalve
species of the mytilid genus Lithophaga, including a new one, are
recorded from Indonesian
mushroom
corals (Scleractinia: Fungiidae). True associations with live hosts include L.
laevigata, L.
lessepsiana,
L. lima, L. punctata spec. nov., and L. simplex, while
specimens of L. malaccana and L.
mucronata
have been found in bore holes in encrusted or dead parts of infested
corals.
Diagnosis
for L. punctata n.s.: Valves with minute, elevated dots antero-laterally
to postero-ventrally,
periostracum
darker above that area. Largest available specimen: 13.5-5.0-4.7 mm. Host
corals are
Fungia
(Pleuractis) paumotensis, F. (Verrillofungia) repanda, F. (V.) scabra,
Halomitra pileus,
Lithophyllon
mokai, and Sandalolitha robusta.
Host
corals of L. laevigata are Fungia (V.) scabra, and F. (V.)
spinifer.
Host
corals of L. lessepsiana are Fungia (Danafungia) horrida, Halomitra
pileus, Herpolitha limax,
and Lithophyllon
undulatum.
Host
corals of L. lima are Fungia (P.) moluccensis, F. (V.) scabra,
Lithophyllon undulatum.
Host
corals of L. simplex are Fungia (Wellsofungia) granulosa, and Sandalolitha
robusta.
It is
obvious that there is no clear host-specificity in the associations of Lithophaga
and mushroom
coral
species.
The
present results suggest that the Lithophaga species recorded from
mushroom corals at the
Spermonde
Shelf, South Sulawesi, predominantly occur on nearshore reefs..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
54
GROWTH
CHARACTERISTICS OF THE CORAL-ASSOCIATED BACTERIAL
COMMUNITY
IN HEALTHY, STRESSED, AND DISEASED CORALS
David
Kline, Mya Breitbart, Nancy Knowlton, Forest Rohwer
Marine
Biology Research Division
Scripps
Institution of Oceanography
University
Of California, San Diego
La
Jolla, CA 92093-0202 USA
dkline@ucsd.edu
Coral
disease incidence has increased dramatically since first being reported in the
early 1970s.
Increasing
numbers of coral colonies and species over wider geographical ranges are
affected by
disease,
resulting in extensive mortality throughout the Caribbean. Despite the major
ecological
impact
of coral disease, the etiology of most coral diseases remains unclear. Corals
harbor unique,
associated
microbial communities. These coral-associated bacterial communities are
diverse, species
specific,
and similar in corals from widely separated reefs. The nature of the
relationship between
corals
and their associated bacteria has yet to be established. The balance of a
symbiotic relationship
is
not static, and under stressful environmental or physiological conditions it is
possible that the
associated
symbionts can multiply and cause disease. Whether any of the uncharacterized
coral
diseases
are caused by imbalances in the regulation of the normally associated
microbiota remains to
be
determined. Mitchell and Chet (1975) demonstrated that certain stresses kill
corals via bacterial
overgrowth
(i.e., coral treated with antibiotics did not die when exposed to crude oil,
copper sulfate,
or
dextrose). However, the Mitchell and Chet study used concentrations of
stressors that are unlikely
to
occur even on extremely polluted reefs. This study expanded upon the work of Mitchell
and Chet
(1975)
by testing a greater range of environmental and anthropogenic stresses, at more
environmentally
relevant concentrations. To elucidate the nature of the relationship between a
coral
and
its associated bacteria, methods were developed to determine bacterial growth
rates and numbers
on
corals. These methods were used to determine how the bacterial community growth
characteristics
change with anthropogenic stress and disease. Our results indicate that the
coral-associated
bacterial
community is tightly regulated, possibly through nutrient limitation, and this
regulation
breaks down with carbon (glucose) addition and disease..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
55
GENETIC
POPULATION STRUCTURE OF THE LIONFISH
PTEROIS
MILES (SCORPAENIDAE: PTEROINAE) IN THE GULF OF AQABA AND
NORTHERN
RED SEA
Kochzius
M, Söller R, Khalaf MA, Blohm D
Department
of Biotechnology and Molecular Genetics, FB2-UFT,
University
of Bremen, P.O. Box 330440, 28359 Bremen, Germany
Fishes
on coral reefs, such as the lionfish Pterois miles, have a life history
with two totally different
phases:
adults are relatively strongly side-attached, whereas larvae of virtually all
species are
planktonic.
Therefore, large-scale dispersal and high gene flow could be expected. However,
due to
the
fjord-like hydrography and topology of the Gulf of Aqaba isolation of
populations might be
possible.
The gulf is a 180 km long and 6-25 km wide northern extension of the Red Sea
and
separated
by a shallow sill. The aim of this study is to reveal genetic population
structure, genetic
diversity,
and gene flow between populations of the lionfish P. miles in the Gulf
of Aqaba and
northern
Red Sea. The applied molecular marker is a 166 bp sequence of the 5’
mitochondrial control
region.
It is the most variable mitochondrial gene in fishes and a suitable marker to
investigate
genetic
population structure. Among 94 P. miles specimens 32 polymorphic sites
were detected,
yielding
38 haplotypes. Sequence divergence among haplotypes ranged from 0.6% to 9.9%
and
genetic
diversity was high (h=0.85, =1.9%). AMOVA indicates no restriction of
gene flow between
the
Gulf of Aqaba and northern Red Sea ( ct =
0.05258). Consideration of observed high genetic
diversity,
paleoceanography of the Red Sea, and life history of P. miles indicate
that the revealed
genetic
population structure reflects high gene flow and panmixia. However, it is not
possible to
estimate
on which time-scale gene flow operate. Therefore, coastal zone management in
the Gulf of
Aqaba
has to follow the precautionary principle and should not rely upon fast
replenishment or re-colonisation..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
56
STRATEGIES
IN SURVIVAL OF CORALS FROM STRESSED ENVIRONMENTS:
FUNGIA
GRANULOSA A CASE STUDY
E.
Kramarsky-Winter, Y. Loya
Dept
of Zoology, George S. Wise Faculty of Life Sciences,
Tel
Aviv University, Tel Aviv, Israel
wintere@post.tau.ac.il
Coral
reef degradation due to anthropogenically induced stress has recently been the
cause of much
concern
For corals found in these areas, the ability for sustaining the population
depends on the
survival
at the individual (clone) level as well as at the genet level. Survival at the
individual level is
a
result of the individual”s capacity for physiolo gical plasticity. Reproduction
and the ability to repair
damage
are two aspects of the coral’s physiology that play cardinal roles in their
ability to survive
stress.
In the Red Sea the solitary free living fungiid coral Fungia granulosa, is
common in areas of
high
sedimention and physical abrasion, thus providing a good model system for
studying the
mechanisms
for overcoming stress. To ascertain what physiological adaptations may aid
these corals
to
survive, the reproductive cycle and capacity for repair following damage was
followed for a period
of
three years using standard histological techniques and in situ obsrevations.
Moreover the effect of
tissue
damage on reproductive effort and conversely of reproductive state on the
capacity for repair
was
examined in experimentally manipulated corals. Results showed that F.
granulosa is a
gonochoric
broadcast spawner. Gametogenesis begins in early March at a time of high
productivity in
the
Gulf of Aqaba. Only individuals over 5.0 cm in diameter are reproductive.
Spawning occurs in
July-
August when the water in the Gulf is relatively calm. This led to the choice of
spring and fall as
the
experimental periods for inflicting tissue lesions. Lesions were inflicted on
mature and immature
corals
using an air pick and the corals were maintained in situ. This procedure
was carried out on one
set
of corals during gametogenic months (spring), and on another set during post
reproductive months
(fall).
Tisse repair and regeneration were monitored using photography and computerized
image
analysis.
Corals that underwent damage during post reproductive months, underwent complete
repair
within
8 weeks, while those that were damaged at the beginning of gametogenesis did
not. Immature
corals
did not undergo complete repair regardless of season. Moreover when
reproductive effort was
investigated
two months following removal of 30% of surface tissue, results showed that
fecundity
was
reduced by 50%, though gametogenesis continued, indicating cellular and
energetic trade-offs
between
the two processes. The relationship between amount of tissue damage and tissue
repair in
this
coral was also studied. Corals that had up to 50% of the oral surface tissues
removed underwent
complete
repair providing at least part of the polyp mouth remained. When the polyp
mouth was
removed
coral tissues began developing new mouths buds. In addition following periods
of
“catastrophic”
disturbances where many individuals underwent extensive damage to their tissues
the
corals
survived by a reorganization of the remnant tissues and the formation of buds
which then grew
into
new polyps. A model illustrating how environmental disturbance affects the
relationship between
regeneration
and reproduction is proposed..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
57
CYCLONE
PUMPING AND SEDIMENT PARTITIONING IN THE DEVELOPMENT OF
THE
GREAT BARRIER REEF SHELF SYSTEM
Piers
Larcombe, Bob Carter
Marine
Geophysical Laboratory, James Cook University,
Townsville
4811 Australia
piers.larcombe@jcu.edu.au
Understanding
the relative impact on shelf sediments of daily low-energy versus episodic
high-energy
phenomena
(e.g. cyclones, tsunami) is crucial to our understanding of how shallow water
sedimentary
systems function. Around 30-40% of today’s continental margins lie in the
tropics and
sub-tropics,
where cyclones are major mechanisms of sediment supply to the shelf, and
sediment
transport
upon it. Understanding the sedimentary dynamics of tropical shelves at various
stages of sea
level
is therefore a fundamentally important issue. However, current sedimentation
models for
tropical
shelves are strongly influenced by studies of ocean plateaux such as the
Bahamas, and often
do
not fit well with the characteristics displayed by mixed terrigenous-carbonate
systems, which are
geologically
common and important in petroleum exploration.
The
modern Great Barrier Reef (GBR) is part of the world’s largest and best known
mixed
terrigenous-carbonate
continental margin. The GBR shelf contains three shore-parallel sedimentary
belts.
An inner shelf zone of terrigenous sedimentation at depths of 0-22 m; a middle
shelf zone of
sediment
starvation at depths of 22-40 m; and an outer shelf reef tract with its inner
edge at c. 35-40
m
depth. These zones are controlled by the dynamics of northward, fair-weather,
alongshelf drift,
driven
by southeasterly trade winds, and by the regular passage of tropical cyclones.
Cyclones cause
wind-driven
north-directed middle shelf flows in excess of 130 cm/s, which erode the
seabed,
concentrate
the sparse mobile sediment into sand ribbons, and advect suspended load onto
the outer
part
of the nearshore terrigenous sediment prism and into inter-reef depocentres
within the reef
complex.
Cyclones largely control the input of new sediment into the Great Barrier Reef
system, via
river
flooding, seabed erosion or reef breakage. They also help to control the
partitioning and
dispersion
of the main shore-parallel belts of terrigenous inner shelf, sediment-starved
middle shelf,
and
outer shelf carbonate reef tract sediment. Acting as a sediment pump,
especially during
interglacial
highstands, cyclones have exerted great control on the development of the
modern GBR
province
and its sediments by maintaining a broad shelf-parallel zone of episodically
mobilised
sediment
and scoured seabed, upon which coral reefs have been unable to form.
Contrary
to current models, (i) GBR storm beds are most likely to be preserved intact
close to the
shoreline,
and they also become coarser-grained away from the shoreline; and (ii) for the
central
GBR,
“highstand shedding” only applies to carbonate sediment at the scale of local
reefs; system-wide,
oceanographic
controls cause high rates of carbonate sedimentation on the slope during both
sea-level
rise and highstand; concomitantly, terrigenous sediment accumulates fastest on
the slope
during
sea- level rise, and slowest during sea- level lowstand and highstand..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
58
THE
SUCCESS OF DANJUGAN ISLAND MARINE RESERVE AND SANCTUARIES
LEADS
TO A NETWORK OF PROPOSED MARINE PROTECTED AREAS IN NEGROS
OCCIDENTAL,
WESTERN VISAYAS, PHILIPPINES
Gerrardo
L. Ledesma 1 , Jean-Luc Solandt 2 and Peter Raines 2
1 The Philippine Reef and Rainforest
Conservation Foundation, Inc.,
#3
Dona Ceferina Building,
Mandalagan,
Negros Occidental,
Philippines
gll@mozcom.com
2 Coral Cay Conservation Ltd., The Tower, 125
High Street, London SW19 2BL, UK
jls@coralcay.org
The
Danjugan Island Marine Reserve and Sanctuaries (DIMRS) (Cauayan municipality,
Negros
Occidental,
Philippines) was established via a collaborative project that pioneered a
unique approach to
marine
resource management. The Philippine Reef and Rainforest Conservation
Foundation, Inc.
(PRRCFI)
has been working in partnership with Coral Cay Conservation (CCC) since 1995,
in order to
carry
out survey and education work to create the DIMRS, which was fully gazetted in
February 2000
by
the provincial council. Baseline surveys and training of fisherfolk, community
members and
government
personnel has expanded since 2000 to the adjacent municipalities of Sipalay and
Hinoba-an
where
further potential reserve areas have been proposed. This work has come under
the umbrella of
a
provincial environmental programme called The Southern Negros Coastal
Development Programme
(SNCDP).
A local community (Barangay Elihan) has requested to have their own marine
sanctuary due
to
the success of DIMRS, and with the assistance of PRRCFI and CCC scientists,
surveys have been
carried
out together with trained local community members to help establish reserve
boundaries. This
area
has particularly high coral cover for Negros Occidental, and good potential for
future coral
accretion
through recruitment and adult coral growth. Similarly, after initial CCC
surveys in early
2000,
further marine reserves have been recommended in other municipalities, and
PRRCFI aim to
continue
the work of the SNCDP within the municipalities of Sipalay and Hinoba-an.
Therefore, as a
result
of baseline marine biological surveys coupled with community education and
technical training
by
the PRRCFI/CCC partnership, there has been an increase in the number of
potential and existing
marine
protected areas in Negros Occidental as a knock-on effect of the successful
establishment of the
DIMRS.Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
59
COLD-WATER
CORAL REEFS ALONG THE NORTHERN NORWEGIAN MARGIN
Björn
Lindberg, Christian Berndt, Jürgen Mienert
Dept.
of Geology, University of Tromsř 9037
Tromsř,
Norway
Bjorn.Lindberg@ibg.uit.no
The
University of Tromsř studies the northernmost known occurrences of cold-water
reefs as a
contributor
to the EU- funded program ECOMOUND (Environmental Control on Mound Formation
along
the European Margin). The presence of cold-water coral reefs along the entire
coast of Norway
has
been known for some time, but the reefs have only recently been subjected to
thorough stud ies.
Several
prerequisites for the existence of the reefs are known, including water
temperature, current
activity
and the presence of hard substrate on which reef- growth can initiate. Several
of the reefs
found
on the Norwegian margin seem to be closely linked to micro-seepage of
hydrocarbons from
deeper-lying
reservoirs, but elevated HC- levels have not been proved at all locations. The
question
still
remains, whether or not the presence of the reefs is linked to the local (and
regional) sub-surface
geology.
High-resolution
acoustics (seismics and side-scan sonar), video- imaging, coring, HC-analyses
and
isotope-analyses
provide a solid data-set for the study of the Fuglřya reefs (first discovered
by
Hovland
et al. during a pipeline survey). The reefs can be more than 30 m high and
are dominated by
Lophelia
pertusa. They are found from 130 to 180 mbsl, consistently located on
topographic highs of
morainic
material deposited during the last glaciation. The oceanic conditions are
strongly influenced
by
the influx of Atlantic water (Norwegian Current) with temperatures of ~7.7°C
and salinity of
34.7‰,
and tidal currents with velocities up to >30 cm/s were measured. A local
basin containing
primarily
sandy sediments nearby the reefs displays circular depressions of ~5 m depth
and ~20 m
diameter,
interpreted to be pockmarks due to migration of fluids from the sub-seafloor.
The region is
on
the boundary to the Barents Sea, and existing geologic maps indicate that the
underlying bedrock
is
crystalline, thus pointing towards a non-thermogenic origin of the migrating
fluids causing the
pockmarks
in the area.
Further
studies of the reefs can assess their value as an indicator of the sub-surface
geology as well as
a
possible paleoclimatic proxy, given that the d
13 C and d 18 O values are linked to
the environment in
which
the corals grow, and the parameters are recorded in the skeleton..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
60
REEF
GROWTH AND ACCRETION IN A TURBID LAGOON ENVIRONMENT
Iain
A. Macdonald
Manchester
Metropolitan University
Department
of Environmental and Geographical Sciences, John Dalton Building, Chester
Street,
Manchester, M1 5GD, UK
Turbid
reefs have been the subject of many ecological investigations and have commonly
been
associated
with lower living cover of benthic organisms, decreased diversity of organisms
and a
general
range reduction of fore-reef bathymetric zonation. Whilst these studies stress
the impacts of
increased
sedimentation on reef composition, the longer-term potential for carbonate
accumulation
and
the processes controlling accumulation under these conditions remain poorly
understood.
This
study examines these processes within a lagoon environment at Discovery Bay,
Jamaica. The
site
is naturally turbid, and these conditions are exacerbated by additional
external inp uts of bauxite
dust.
This results in high mean sedimentation rates (average 5.2 ± 2.2 mg.cm -2 d -1 ),
although at times
these
reach the proposed threshold levels (10 mg.cm -2 d
-1 ) beyond which reef development is
suppressed.
In-situ measurements of light also indicate high attenuation rates, such
that the surface
illumination
is reduced to 9.5% at 15m depth. Models are presented which illustrate patterns
of reef
development,
community structure and framework preservation for shallow (0-10 m) and deep
(15-25
m)
parts of the site.
Shallow
sites are characterised by a rigid reef structure of dead in-situ Acropora sp.
Live coral cover
is
minimal (3.7%) with Siderastrea sp. (domed morphology) and Madracis
mirabilis dominating.
Sediment
production is dominated by the calcified green algae Halimeda sp. (5m –
19.7%; 10m –
39.0%)
and the articulated coralline algae Amphiroa sp. (5m – 37.6%; 10m –
16.0%). Framework
preservation
is influenced by high rates of internal bioerosion (mainly by sponges and
worms) and
low
encrustation rates (coralline algae and the foraminifera Gypsina plana dominate
the secondary
framework
community). In combination these factors contribute to a predicted low
accretion rate.
Deep
sites are characterised by loose sediment with little solid reef structure.
Live coral cover is very
low
(5.4%). Montastrea annularis dominates the coral community and exhibits
flat tiered growth
morphologies.
Partial mortality and rejuvenation are common. Sediment production is dominated
by
bivalves
(20m – 36.5%; 25m – 39.5%). Framework preservation is influenced by high
infestation by
internal
bioeroders (particularly sponges and bivalves) and by minimal encrustation
(mainly
serpulids).
In combination these factors contribute to a predicted very low accretion rate.
This
study demonstrates restricted framework development under conditions of high
sedimentation
and
turbidity, coupled with only a small effect from secondary framework
contributors and an
infestation
of borers. The major sediment contributors (Amphiora sp., Halimeda sp.,
and bivalves)
also
differ from typical fore-reef (coral dominated) assemblages. Overall, low
carbonate
accumulation
rates are predicted for these reefs..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
61
TROPICAL
REEF COMMUNITIES OFF NORTH CAROLINA: AT THE NORTHERN
LIMIT
ALONG THE US EAST COAST
Ian
G. Macintyre
Smithsonian
Institution, National Museum of Natural History,
Washington,
DC 20560, USA
Two
species of zooxanthellate or tropical reef corals occur in patches on flat rock
outcrops in Onslow
Bay,
North Carolina. Solenastrea hyades (Dana) and Siderastrea siderea (Ellis
and Solander) were
found
in water depths of about 20 to 40 meters. These corals survive temperatures of
less than
16degC
for three months of the year (mid-January to mid-April), which is the generally
accepted
minimum
tolerance limit for the survival of tropical reef corals. These corals were
found scattered on
mostly
Miocene quartz sandstone outcrops and are not forming a reefal framework.
Dominantly
tropical
benthic macro algae and a variety of tropical reef fish are associated with
these reef patches.
Rock
outcrops are abundant in Onslow Bay because of a restricted sediment supply
related to limited
river
outflows. These suitable substrates and the inshore migration of the Gulf
Stream during summer
months
are major factors that allow these tropical reef communities to exist so far
north. The inner
depth
limit of about 20 meters is related primarily to a lack of suitable hard
substrate and suspended
sediments
caused by water turbulence. More work is needed to study the life histories of
the two
coral
species to reveal if they are capable of reproducing under these hostile
conditions and also to
document
the settlement periods for their planulae. In addition, more information is
needed on other
groups
that are associated with these tropical coral patches, particularly octocorals
and sponges..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
62
RELATIONSHIP
OF d 13 C VERSUS d 18 O IN
CORAL SKELETONS. A NEW PROXY FOR
ECOLOGICAL
ADAPTATION?
Cornelia
Maier 1 , Jürgen Pätzold 2 , Rolf P.M. Bak 1
1 Royal Netherlands Institute for Sea Research,
P.O.
Box 59, 1790 AB Den Burg, Texel, The Netherlands
2 University of Bremen,
Dept.
of Geosciences, Postfach 33 04 40, 28334 Bremen, Germany
Scleractinian
corals hosting endosymbiotic algae (zooxanthellae) occur over a wide depth
range
within
the photic zone of coral reefs. Different species are distinct in their
distributional depth range,
with
some species being confined to a narrow depth range while others can be found
over the whole
reef
slope. We investigated the skeletal d 13 C versus d 18 O, zooxanthellae densities and photopigments
of
three different species of the genus Madracis. The species M.
pharensis is abundant over a wide
range
between 5 and > 60 m depth, while M. mirabilis and M. formosa are
restricted to a narrow
range
growing shallow (<20 m) or deep (> 40 m), respectively. We hypothesize,
that the distinct
distributional
depth range of the three species is due to adaptation to the respective light
regimes.
Because
coral d 13
C and d 18 O are both controlled by kinetic isotope effects and, because d 13 C
is in
addition
affected by the coral / zooxanthellae metabolism (P:R ratio), any species
specific adaptation
to
particular depth regimes must be reflected in the skeletal d 18 O
versus d 13
C ratios. Apart from
environmental
factors (temperature and salinity), photosynthesis and calcification rate are
controlling
factors
in coral isotope fractionation. The efficiency with which corals under various
light regimes
photosynthesize
and calcify, and the linkage between photosynthesis and calcification, become
apparent
when applying skeletal d 13 C versus d 18 O of the 3 Madracis species. The d 13 C
vs. d 18 O
ratios
of e.g. M. pharensis (broad depth range) and M. formosa (narrow
range, deep) - both sampled
at 50
m depth – indicate that M. pharensis has hardly been growing and is
hence at its distributional
depth
limit, while M. formosa has even in 50 m depth a positive P:R ratio and
skeletal growth. We
consider
the ratio of d 13 C and d 18 O a useful ‘proxy’ to determine the
ecological adaptation of single
species
to various depth or light regimes. Moreover applying skeletal d 13 C
versus d 18
O may be a
vital
tool in reconstructing past conditions of reef health and reef growth..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
63
BENTHIC
COMMUNITY STRUCTURE AND SEDIMENT PRODUCTION IN A
FLUVIALLY
IMPACTED EMBAYMENT , RIO BUENO, JAMAICA.
Jennie
Mallela
Manchester
Metropolitan University, Department of Environmental and Geographical
Sciences,
Chester Street, Manchester, M1 5GD, UK
j.mallela@mmu.ac.uk
This
study examines the structure and composition of fluvially impacted coral reef
communities and
associated
sediment production in Rio Bueno, Jamaica. Rio Bueno is a small (ca. 0.5
km wide)
embayment,
located on the northern coast of Jamaica (N 18° 28’, W 077° 27’). The area is
characterised
by clastic sediment and freshwater inputs from the Dornock River, resulting in
abiotic
conditions
exhibiting pulsed fluctuations (e.g. variation in salinity, turbidity,
light attenuation).
Detailed
fieldwork during the summer of 2001 demo nstrated that mean (± SE)
sedimentation rates in
the
central western embayment area were 10.6 (± 0.98) mg cm -2 day -1 . Outer embayment
areas
demonstrated
a mean (± SE) sedimentation rate of 3.1 (± 0.40) mg cm -2 day -1 . In addition to
continual
natural disturbances, the study area has historically been subjected to
mangrove and
seagrass
clearance, whilst the over-exploitation of fisheries resources continues.
Inner
embayment areas appear heavily impacted by the Dornock River, with a substrate
composition
of
close to 100% silt (occasional patches of seagrass (less than 1%) occur). No
other habitat types
occurred
at these innermost sites. Framework production was bathymetrically restricted
to areas
shallower
than 27 - 35 m within the central, fluvially impacted sites. In contrast, the
outer, less
impacted
sites have been demonstrated to support drop-offs to = 200 m, with corals
present to depths
of
=60m. The spatial and bathymetric restriction observed in the central embayment
areas can be
considered
an effect of a highly turbid, reduced- light environment.
Macro
algae and turf dominated the community composition, comprising between 25% and
30% of
benthic
cover in the central fluvially impacted sites, and between 40% and 70% at less
impacted
sites.
However, hard coral cover comprised 9% to 11% of benthic cover at the central
fluvially
disturbed
sites and 8% to 12% at less impacted outer sites.
The
results of the study are discussed in the light of ongoing work, which is
focused on developing a
carbonate
bud get for inner and outer regions of the Rio Beuno embayment area..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
64
GFP-LIKE
PROTEINS AND EVOLUTION OF COLORATION IN REEF ANTHOZOA
Mikhail
V. Matz, Yulii Labas, Konstantin Lukyanov, Sergey Lukyanov
Whitney
Laboratory, University of Florida, 9505 Ocean Sho re Blvd,
St
Augustine, FL 32080, USA
Coral
reef ecosystems are characterized by the amazing variety of colors, but the
evolutionary roots
of
this diversity remain largely unknown. Anthozoa represent a unique case when
each visually
perceptible
basic color is essentially determined by the sequence of a single protein,
homologous to
green
fluorescent protein (GFP) from Aequorea victoria. This provides unique
opportunity to address
the
question of color evolution in the environment directly by applying the tools
of molecular
phylogenetics,
and in addition, to characterize and monitor variations in coloration in terms
of
expression
of individual genes. GFP-like proteins of Anthozoans are a very diverse family
that
existed
in the form of at least four separate lineages even before separation of
sub-classes Zoantharia
and
Alcyonaria. The most surprising fact is that, notwithstanding these ancient
diversity roots,
origination
of new colors seems to happen right now: there are multiple independent events
of color
diversification
observed in the most terminal parts of the phylogenetic tree. Combining this
fact with
the
molecular data obtained for the proteins of different colors, such as results
of site-specific and
random
mutagenesis and X-ray crystallography, we hypothesize that the phylogenetic
pattern and
color
polymorphism in reef Anthozoa is a result of a balance between selection for
GFP- like proteins
of
particular colors and mutation pressure driving the color conversions. An
in-depth phylogenetic
analysis
will clarify whether the color diversification process goes on continuously
within the protein
family,
or we are witnessing a unique one-time event triggered by some environmental
changes in the
recent
past..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
65
CORAL
RECORD OF RIVER RUNOFF AND HUMAN IMPACTS ON THE INNER GREAT
BARRIER
REEF OF AUSTRALIA
Malcolm
McCulloch, Stewart Fallon, Timothy Wyndham,
Erica
Hendy, Janice Lough, David Barnes
Research
School of Earth Sciences, Australian National University, Canberra 0200, and
Australian
Institute of Marine Science, Townsville, Australia
The
impact of European settlement on water quality in the Great Barrier Reef (GBR)
of Australia is a
longstanding
and still highly controversial issue. Studies of erosion and sediment transport
in river
catchments
have shown substantial increases since European settlement; a consequence of
large-scale
modification
of the river catchments from grazing, agriculture, mining and associated
activities such
as
land clearing. The magnitude and scale of these anthropogenic induced changes
and importantly
their
impact on the marine environment, however remains highly uncertain. Here we
describe a new
approach
to assist in the quantification of both anthropogenic and natural
(pre-European) sediment
fluxes
entering the GBR. This approach is based on the application of in-situ
geochemical tracers in
corals
and has the advantage of providing a direct quantitative measure of the
sediment/nutrient (P)
fluxes
that are actually reaching coral reefs.
Using
the relatively new technique of high resolution (weekly to fortnightly) laser
ablation ICP-MS,
continuous
scans of the trace element compositions were undertaken on 300-400 year old Porites
coral
cores (growth rate of ~1-2 cm per year) from the GBR of Australia. During high
intensity
rainfall
events, there are massive discharges of freshwater and suspended sediments into
the GBR
lagoon,
particularly from the Burdekin River. Barium concentrations in corals, a tracer
of suspended
sediment
load, reveals two distinctive patterns. In the 1770’s when Captain Cook first
explored the
east
coast of Australia, there is only limited evidence for flood-plume related
suspended sediment
fluxes
entering the inner GBR. However, immediately following European settlement in
1870, there
is a
sustained increase in the Ba during flood events. This is indicative of a significant
increase in
suspended
load being delivered to the inner GBR, coincident with the first grazing
activities by
European
settlers in the river catchments of the GBR. These results therefore provide
unequivocal
evidence
for river flood-plumes transporting substantially increased fluxes (x4 to x8)
of suspended
sediment
and hence nutrients into the inner GBR reef. Sediment fluxes are modulated by
land-use
intensity
and climate, principally droughts. Following the drought of 1968/69, the
suspended
sediment
load increased x3 during the subsequent 1970 flood, presumably due to enhanced
erosion of
the
highly denuded catchments. In the 1970’s and 1980’s sediment loads in the
Burdekin River
further
increased following the introduction of more drought resistant cattle breeds
such as Bos
indicus.
This
study provides both a ‘natural’ pre-European baseline as well as a quantitative
measure of
anthropogenic
fluxes against which reduction of sediment loads to the GBR can be targeted.
Reducing
terrestrial runoff into coral reefs is essential if they are to survive the
lethal combination of
direct
anthropogenic impacts and now climatic stresses from unusually warm ocean
temperatures..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
66
‘EACH
REEF ITS OWN STORY’
SEA-LEVEL,
ISLAND EROSION AND TWO OF J S GARDINER’S ATOLLS: FUNAFUTI
(TUVALU)
AND GOIDHOO (MALDIVES)
Roger
McLean
School
of Geography and Oceanography
University
of New South Wales
Australian
Defence Force Academy
Canberra
ACT 2600 Australia
At
the age of 24, J Stanley Gardiner joined the ‘Coral Reef Boring Expedition’ to
Funafuti atoll for
the
first of the three expeditions to test Darwin’s subsidence theory of coral
reefs. Gardiner spent
upwards
of three months on Funafuti. His 1898 publication appeared in the same year the
third
expedition
ended and six years before the major results of the expedition were published
by the
Royal
Society/British Museum. Among other things, Gardiner concluded that Funafuti
‘had been
elevated
by about 10 feet’ and that the islands on the atoll were ‘now being washed
away’. In 1899
Gardiner
spent 10 days on Goidhoo atoll, the first of the Maldivian atolls he visited
during his six
month
expedition to the Maldives. On Goidhoo, he came to the same conclusions as on
Funafuti, viz
he
found ‘proof of elevation’ as well as the ‘slow but steady erosion’ of islands.
Three decades later,
in
reviewing his own and others work on reefs and islands in the Pacific and Indian
Oceans, Gardiner
admitted
that he ‘had not materially altered his views’, though he had become much more
precise
about
the timing of the higher sea level, endorsing Daly’s deduction that it was
3500-4000 years ago.
What
was Gardiner’s evidence for these conclusions on Funafuti and Goidhoo? Were his
interpretations
similar to those of his contemporary expeditioners and later researchers? And,
how
does
his sea- level history and island erosion hypothesis stack- up now, after 100
years?
This
paper addresses these three questions. Generally Gardiner’s conclusions have
been endorsed.
Indeed,
on the face of it they stack-up pretty well. For instance, Dickinson, in a
recent paper
(Quaternary
Research, 1999) indicates that the shoreline morphology of Funafuti ‘reflects
a relative
mid-Holocene-sea-level
high stand’, and that the shoreline erosion, which is presently occurring on
Funafuti,
foreshadows the potential impact of global warming on atoll islands.
Dickinson’s evidence
on is
based primarily on field observations and data from secondary sources, as well
as a notion of
where
Funafuti fits within the regional sea- level context.
An
extensive geomorphic survey, including levelling profiles and mapping all of
the islands on
Funafuti,
and a more modest survey using similar techniques on Goidhoo atoll has been
carried out
by
the author and colleagues. These surveys, showed no indisputable evidence for a
higher mid-Holocene-
sea-
level high stand nor any evidence for chronic island erosion, apart from
shorelines that
have
been subject to substantial modification from human impact. Radiometric dates
from reef flats
and
islands of both atolls are consistent with this view, which is contrary to the
conclusions of
Gardiner
and other workers on Funafuti and Goidhoo. Reasons for this situation are
advanced,
including
the views of some of Gardiner’s contemporaries which were more ambiguous about
the
field
evidence..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
67
DOES
SUBSISTENCE FISHING INFLUENCE SEA URCHIN POPULATIONS IN FIJI?
Rebecca.
E. Mitchell, N. K. Dulvy, N. V. C. Polunin
Department
of Marine Sciences and Technology
University
of Newcastle upon Tyne
Ridley
Building
Newcastle
upon Tyne NE1 7RU, UK
If
fishing alone determines sea urchin abundance through removal of predators and
grazing
competitors,
then urchin density will be greater on reefs with higher exploitation pressure
where
other
anthropogenic impacts do not exist. We tested whether sea urchin abundance
differed across a
gradient
of fishing pressure among thirteen traditional fishing grounds, in a region of
Fiji where
additional
human disturbances are negligible. The abundance of sea urchins in Lau was low,
ranging
from
0.1-0.8 urchins m -2 , and although
differences in both their total abundance and diversity were
evident
among grounds, these differences did not relate systematically to variations in
fishing
pressure
or benthic variables. Only the abundance of juvenile urchins indicated a
positive relationship
with
fishing pressure. Multiple regression models were used to explain relative
influences of benthic
variables
alongside fishing pressure, but significant results with juvenile urchins appear
to be
influenced
primarily by the most heavily fished ground. We conclude that in the absence of
other
anthropogenic
inputs, recruitment to adult urchin populations at low subsistence- levels of
fishing is
more
likely to be driven by a combination of processes rather than by predation
alone..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
68
PETROGRAPHIC
AND GEOCHEMICAL ANALYSIS OF A NON-TROPICAL
MEDITERRANEAN
CORAL (Cladocora caespitosa): IMPLICATIONS FOR ITS USE AS A
PALAEOCLIMATIC
PROXY
Montagna
Paolo, Mazzoli Claudio, Silenzi Sergio, Corain Livio
Dept.
Mineralogy and Petrology, Padova Univ., C.so Garibaldi 37, I-35137 Padova,
Italy
paolo.montagna@unipd.it
Many
palaeoclimatic studies focus on the atmosphere-ocean relationship as the major
point to
understand
decadal and longer-term climate variability. Although the most evident effects
of climate
changes
on seawater mainly concern the oceans, also in minor basin, such as in the
Mediterranean
Sea,
deep and complex changes are commonly observed and therefore they could be
analysed,
studied
and related to the global climate system.
The
highly seasonal nature of the Mediterranean climate regime makes this region
particularly
sensitive,
and potentially very vulnerable, to climate changes. Thus there is a need for
rigorous
assessment
of the patterns, causes and impacts of Mediterranean climate fluctuations. Such
understanding
needs reliable measurements of relevant parameters, such as sea surface
temperature
(SST),
for an adequate interval of time; in the lack of both instrumental observations
and historical
records
of relevant meteorological parameters we have to rely on indirect measurements
(proxy
data),
such as corals.
A
living non-tropical coral (Cladocora caespitosa) (L.) from the
North-western Mediterranean Sea,
has
been examined by optical polarized light (PL) and scanning electron microscopy (SEM)
and
chemically
analysed by electron (EMPA) microprobe with the aim to define in detail its
microstructural
features and determine the reliability of its use as a palaeo and living
environmental
and
climatic proxy. Petrographic observations and geochemical data show different
morphological
and
compositional portions of the primary aragonitic texture of the coral and the
presence of a
secondary
aragonitic precipitation (interseptal filling). Aragonitic crystals that form
interseptal
filling,
show lamellar arrangement completely different from trabecular structure that
forms septa,
paliform
lobes and theca wall. Different morphological features were analysed, and
geochemically
characterised.
The aim of the research was to carry out a detailed investigation on the
calcification
centres,
the needle-shaped crystals and the interseptal fillings, by studying the
distribution of minor
and
trace elements such as Sr, Mg, S, Si and Al, in order to recognise possible
microchemical
differences
in small coralline areas and reveal little scale heterogeneities which are
averaged in
conventional
bulk sampling techniques.
Minor
and trace element distribution between centres of calcification and the
surrounding fibres in
different
areas of the corallite has been pointed out. Small spatial scale study has
allowed to
determine
the microstructural geometry of the coral and its geochemical features,
improving the
analytical
methods for the future use of C. caespitosa as a environmental proxy
(SST, Salinity,
anthropogenic
inputs, etc.). This study has been extremely important to understand how to
obtain
geochemical
information from primary aragonite, without a contamination of a secondary
aragonitic
contribution.
Since C. caespitosa is the only shallow coral existing in the
Mediterranean Sea, such
petrographic
and geochemical characterization is fundamental to prove the reliability of
this species
as a
climate proxy, and it offers the possibility to obtain long time series, never
documented before in
the
Mediterranean marine environment..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
69
EARLY
MARINE DIAGENESIS IN CORALS AND CONSEQUENCES FOR PALEO-RECONSTRUCTIONS
OF
CARBONATE SATURATION STATE IN CORAL REEFS AND
ATMOSPHERIC
CO2
Anne
Müller 1 , Michael K. Gagan 2 , Janice M. Lough 3
1 Department of Geology, Australian National
University, Canberra, ACT 0200 2 Research
School of Earth Sciences, Australian National University, Canberra, ACT 0200
3 Australian Institute of Marine Science, PMB 3,
Towns ville MC, QLD 4810, Australia
A
major and recently topical question concerns the effect of increasing
atmospheric CO2 on coral
calcification
rates. Coral calcification rates have been used to derive information on
carbonate
saturation
state in the ocean and to derive conclusions on atmospheric CO2 levels in the past and
future.
We present coral skeletal density, extension, calcification, d 18 O
and d 13 C
data for two long
coral
cores spanning ~ 1840-1994 AD at Ningaloo Reef Marine Park, Western Australia,
one of
which
includes significant secondary precipitation of marine inorganic aragonite. We
show that this
secondary
aragonite can lead to the incorrect conclusion of reduced calcification in the
20th. In our
coral,
a 30% cementation at the start of the century corresponds to the decrease in
calcification
towards
the present derived from modeling and experimental studies. While calcification
rates alone
are
ambigous for conclusions on reef calcification and coral growth, calcification
rates in
combination
with d 13
C values allow to see diagenetic alteration in recent corals.
Furthermore, the
combined
use of coral density, growth rate and calcification data supports correct
conclusions on
coral
calcification. We show that diagenesis can seriously effect paleoceanographic
reconstructions
from
calcification rates and d 13 C and may have serious implications for
paleo-CO2 reconstructions
and
conclusions on past episodes of coral bleaching..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
70
THE
KEY LARGO LIMESTONE REVISITED: PLEISTOCENE SHELF-EDGE FACIES,
FLORIDA
KEYS, USA
H.G.
Multer 1 , E. Gischler 2 , J. Lundberg 3 , K.R. Simmons 4 ,
E.A. Shinn 5
1 9855 State Route 961-F, Arkport, NY 14807, USA
2 Geologisch-Paläontologisches
Institut, J.W. Goethe -Universität, 60054 Frankfurt/Main, FRG 3 Dept. Geography, Carleton University, Ottawa
Ontario K1S 5B6, Canada
4 US Geol. Survey, Federal Center, Denver CO
80225, USA 5 US Geol. Survey, St.
Petersburg FL 33701, USA
The
southern margin of the Pleistocene Florida Platform is well known from the
coral-bearing Key
Largo
Limestone and the ooid-rich Miami Limestone that crop out along the island
chain of the
Florida
Keys between Miami and Key West. These units were deposited during the last
interglacial
highstand
of sea level ca. 125 yr BP (oxygen- isotope stage 5e). Based on
sedimentological and
chronological
(U-series dating) investigations of 12 long and 57 short cores, the youngest of
the
Pleistocene
Q-units (Q1-Q5) of the Key Largo Limestone of south Florida was further
subdivided
into
Q5e and post-Q5e. Individual units correspond to highstands of sea level, and
units are, to a
large
part, separated from each other by subaerial exposure horizons reflecting sea
level lowstands of
the
Pleistocene. Units Q1 and Q2 are characterized by abundant quartz and to a
lesser extent by
skeletal
fragments of molluscs and foraminifera. We speculate that units Q1 and Q2 may
have been
deposited
during the high sea levels of oxygen-isotope stage 11 between 420-360 ka.
Abundant
carbonate
production and reef development occurred during deposition of unit Q3,
presumably
during
isotope stage 9. The abundance of corals and coral boundstone decreases in unit
Q4
(corresponding
to isotope stage 7), which can be subdivided in a lower quartz-rich and an
upper
carbonate-rich
succession. Unit Q5e (equivalent to isotope stage 5e), which forms the present
day
emergent
Florida Keys, is again rich in massive corals (Montastrea annularis) and
reefs. The
seaward-dipping
geometry of this unit and the scarcity of the Atlantic breakwater Acropora
palmata
support
the contention that this Q5e platform margin had a ramp-type character. Shelf-
margin reefs
with Acropora
palmata developed during deposition of post-Q5e units and correspond to
highstands
of
sea level during isotope stages 5a and 5c. These deposits, which exhibit shelf
margin wedge and
offshore
outlier reef geometries, act as foundations of the Holocene bank barrier reefs
at the modern
south
Florida shelf edge..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
71
DO
COMPETITIVE HIERARCHIES EXIST IN CORAL-ALGAL INTERACTIONS?
M.
M. Nugues, M. van der Geest, H. Waska, R.P.M. Bak
Netherlands
Institute for Sea Research (NIOZ), PO Box 59,
1790
AB Den Burg, Texel, The Netherlands
Over
the past two decades, many coral reefs in the Caribbean have experienced an
increase in the
abundance
of macroalgae which has resulted in a greater frequency of direct encounters
between
corals
and macroalgae. Yet, few studies have examined how these interactions and their
effects vary
with
species characteristics and anthropogenic influence and whether they form
definite and
consistent
hierarchical structure. Here, naturally occurring interactions between corals
and three
species
of macroalgae, Halimeda opuntia, Dictyota menstrualis and Lobophora
variegata, were
surveyed
at two different depths on six reefs along the South coast of Curacao,
Netherlands Antilles.
Reefs
were chosen upstream and downstream of local human impacts to represent a gradient
of
human
influence. Damage to both parties in interactions was recorded in the form of
recently dead,
bleached
or discolored coral tissue or physical damage to the alga. In addition,
experimental field
contacts
between corals and algae were conducted to study the competitive abilities of
different coral
species
and the mechanisms of damage to the algae. The survey showed the number and
impact of
interactions
to depend on both coral and algal species, but also on reef location along the
gradient.
Upstream
reefs showed fewer interactions and less damaged coral tissue per interaction
at both
depths
compared to downstream reefs, suggesting a strong influence of local human
factors. The
forced
interactions experiments did not always reflect the pattern observed in the
reef survey. Results
indicated
differences in aggression among corals, with some species able to damage algal
blades by
extrusion
of mesenterial filaments. However, in the field, overgrowth and damage of these
corals by
macroalgae
was conspicuous. The complexity of the development of dominance pattern over
time
and
variation in environmental factors may preclude any consistent competitive
hierarchies between
corals
and algae..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
72
DYNAMICS
OF FISH ABUNDANCE ACROSS BOUNDARIES OF A NO-TAKE ZONE IN
NABQ
MANAGED RESOURCE PROTECTED AREA, SOUTH SINAI
Rupert
F.G.Ormond, Jennifer S. Ashworth, Randolph J. Velterop
University
Marine Biological Station
Millport,
Isle of Cumbrae, KA28 0EG
Underwater
visual census counts were conducted across a small no-take zone and its
adjacent open
fishing
zones in Nabq with the aim of analysing fish abundance and size distribution
across boundary
areas
at three depths and for eight fish families. Although fishing pressure from the
artisanal
Bedouin
fishery is considered moderate, differences in fish abundance since reserve
creation have
been
found and this study provides a more detailed examination of the reserve
dynamics. The
families
Serranidae (groupers) and Lethrinidae (emperors) displayed higher abundance in
the no-take
zone
over all depths whereas Acanthuridae (surgeonfishes) showed the reverse pattern
of increased
abundance
in the open areas. Fishing gear is predominantly gill and trammel nets leading
to
differential
fishing pressure at the various depths surveyed with deeper areas of reef slope
too deep
for
the nets, resulting in altered patterns of abundance with depth. Seven of the
eight families showed
significantly
higher abundance in the no-take zone in the backreef lagoon, whereas only two
families
showed
significant differences in abundance at 10m depth. Gradients of abundance from
the centre
of
the reserve outwards were also influenced by depth, with Siganidae
(rabbitfishes) showing a
decrease
in abundance from the centre in the lagoon but an increase at 3m and 10m. One
species
each
of snapper and grouper (Lutjanus ehrenbergi and Cephalopholis argus)
showed a significant
decrease
in abundance with distance from the reserve centre (over the combined depths)
whereas four
species
of surgeonfish (Acanthurus nigrofuscus, Ctenochaetus striatus, Zebrasoma
desjardinii and
Naso
unicornis) and one species of rabbitfish (Siganus argenteus) showed
significant increases in
abundance.
Habitat differences coupled with differential fishing pressure (both between
depths and
areas),
the small size of the no-take zone and imperfect enforcement of fishing
regulations have lead
to
varying dynamics across this no-take zone..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
73
EARLIEST
STEPS OF DIAGENESIS IN LIVING SCLERACTINIAN CORALS:
EVIDENCE
FROM ULTRASTRUCTURAL PATTERN
AND
RAMAN SPECTROSCOPY
Christine
Perrin 1 , David C. Smith 2
1 Laboratoire de Paléontologie, 8 rue Buffon,
Muséum National d'Histoire Naturelle,
75005
Paris, France
2 Laboratoire de Minéralogie, 61 rue Buffon,
Muséum National d'Histoire Naturelle,
75005
Paris, France
In
carbonate skeletons, including corals, the presence of organic matrices is well
known. These
skeletal
matrices have been recognized to play a major role in skeletogenesis and
formation of
biocrystals.
Sleractinian skeletons are therefore characterized by a compositional
heterogeneity which
is
fundamentally based on this organo- mineral duality. Effects of early
diagenesis on scleractinian
skeletons
are primarily controlled by their initial ultrastructural patterns and the
composition and
spatial
distribution of these skeletal organic matrices.
The
earliest stages of diagenesis in coral skeletons have been investigated by
comparing
microstructural
and ultrastructural features from the uppermost skeletal parts of living
colonies (i.e.
previously
occupied by the living soft tissues) with those obtained from the older part of
the same
skeleton.
The various ultrastructural and diagenetic patterns observed with SEM have been
analysed
by
Raman microspectroscopy in order 1) to characterize mineral and organic
skeletal phases in situ,
and
2) to detect transformation of any of these mineral or organic phases due to
very early stages of
diagenesis.
Microstructural
and ultrastructural patterns:
In
addition to its organo- mineral duality, the initial heterogeneity of a
scleractinian skeleton is shown
by
the occurrence of a micron-scale zonation of fibres resulting from incremental
growth during
elementary
cycles of biomineralisation, and also by the presence of two basic structural
features,
fibres
and calcification centres, clearly differentiated from each other. Within the
species analysed,
micro-
and ultrastructural data reveal an additional fine-scale diversity related to
taxonomy. At the
timescale
of colony life, the earliest processes of diagenesis produce a thin fringe of
syntaxial
aragonite
cements, alteration of the incremental zonation of scleractinian fibres and
also preferential
diagenetic
changes within calcification centres. These first modifications of coral
skeletons are
obviously
controlled by the biological ultrastructural characteristics of scleractinian
taxa and also
suggest
that early diagenesis does not necessarily imply drastic changes of
environmental conditions.
Raman
microspectroscopy:
The
characteristic 155 & 1085 cm -1 bands
common to both aragonite and calcite were evident in all
spectra
and attention was thus focussed on the other bands in order to distinguish
these two
polymorphs.
Most spectra revealed no specific trace of calcite. Organic matter has been
recognised in
some
spectra on the basis of several bands in the range typical of C-H vibration. A
few extra bands in
various
spectra have not yet been identified as belonging to organic or mineral matter
or to yet further
parasites.
Hence, at the present time, the existence of organic material is detected with
confidence,
but
no chemical assignment is yet possible..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
74
CORAL
REEFS IN A SILICICLASTIC BARRIER ISLAND SETTING: REEF
DEVELOPMENT
AND SEDIMENT PRODUCTION, INHACA ISLAND, SOUTHERN
MOZAMBIQUE
Chris
Perry
Manchester
Metropolitan University
Department
of Environmental & Geographical Sciences,
Chester
Street, Manchester M1 5GD
c.t.perry@mmu.ac.uk
Inhaca
Island, southern Mozambique (lat: 26 o S,
long: 33 o E) is located towards the
southerly
latitudinal
limits of coral reef growth in the Indian Ocean. The island forms part of a
small barrier
island
complex produced by the northward transport of sediment along the Natal coast.
The island
comprises
a series of high (up to 115 m) vegetated dunes, interspersed by low, freshwater
marsh
areas.
High energy conditions and significant clastic sediment transport occurs along
the eastern
(Indian
Ocean) side of the island, whilst western shores of the island (Maputo Bay)
represent areas of
deposition
and are characterised by low energy conditions, and the development of
extensive
intertidal
sandflats and seagrass beds.
Reef
development around the island is at best patchy and restricted to the margins
of channels which
dissect
the extensive intertidal flats on western and southern fringes of the island.
Three main sites of
coral
growth are currently identified but, at all sites, active framework
accumulation is severely
restricted
(both spatially and bathymetrically). Coral growth is limited to the upper 4–6
m, but
framework
accumulation is only significant in the upper 1–3 m. In many cases large Porites
sp.
‘bommies’
produce a basic reef structure, with other common coral genera including Acropora
sp.,
Favia
sp., Platygyra sp., Pocillopora sp. and Montipora sp..
In addition, the diversity of the reef-associated
fauna
is severely restricted. In contrast to lower latitude reef systems, reef
development is
therefore
both spatially and bathymetrically constrained and reflects low carbonate
production rates
in
these marginal (high latitude) and high turbidity sites.
Sediment
samples recovered from reef and reef-related areas also indicate very low
productivity of
carbonate
sediments. Three main carbonate sediment producing environments are identified,
1) intra-reef
areas,
2) intertidal coral rubble zones, and 3) seagrass beds. Intra-reef sediments
comprise
predominantly
coral (40–50%) and mollusc (15–30%) grains, with secondary coralline algae (5–
10%),
echinoid (~5%) and foraminifera (1–2%). Coral rubble zones are characterised by
mixed
carbonate:siliciclastic
sediments, with corals (~25%), molluscs (~10%) and coralline algae (~5%)
again
representing the dominant carbonate constituents. Siliciclastics comprise
around 50% of the
substrate.
Seagrass beds are also characterised by mixed carbonate:siliciclastic sands,
but with lesser
amounts
of carbonate (typically <20%). Predominant carbonate grains are molluscs
(10–15%) and
foraminifera
(10–15%). Halimeda which is typically an important reef sediment
producer is absent at
all
sites. Areas of open, intertidal sands, which occur between these carbonate
producing areas, are
siliciclastic
dominated (80-90% quartz) with lesser amounts of glauconite, feldspars and
lithoclasts.
Carbonate
grain assemblages do not, therefore, conform to typical chlorozoan (tropical)
associations,
further
emphasising the marginal nature of carbonate production in these high latitude
reef systems..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
75
GRAZER
CLUES TO REVERSING PHASE SHIFTS ON CARIBBEAN REEFS
Nicholas
Polunin, Ivor Williams
School
of Marine Science & Technology,
University
of Newcastle, Newcastle upon Tyne NE1 7RU, UK
Can
we extrapolate the events of the 1980s on shallow N Jamaican reefs to other
Caribbean reefs,
what
does ‘phase shift’ imply, and what do we really know about underlying
mechanisms and their
reversibility?
On deeper (12-15m) reefs where it seems Diadema was never abundant, a
strong
negative
correlation across 19 sites in 5 Caribbean locations between herbivorous fish
biomass and
macroalgae
hints at a gradual, not step-wise, transition via grazing from high- to
low-coral states.
However
there appears to be a limit to the amount of substratum (~60% cover) scarids
and
acanthurids
can keep macroalgal- free at the present time. Further, an experiment in Belize
with
‘pseudocorals’
suggests that loss of coral and limited herbivore pressure can contribute to
macroalgal
overgrowth
through spatial escape from grazing. We suggest that (i) the consequences of
coral
bleaching,
disease and hurricane impacts and (ii) loss of grazing fish through fishing
contributed to
large
scale algal overgrowth on deeper reef tracts. The Jamaican phase shift (i)
appears not to be a
systemic
switch between alternative states more (ii) a dramatic change which occurred in
a short
space
of time. Systematic comparison of protected reefs with those unprotected from
fishing tends to
remind
us that at shallow and deep reefs the connection between fishing and the phase
shift has been
indirect;
reef degradation will not simply be reversed by excluding fishing..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
76
DEVELOPING
CORAL REEF DATABASE WITH WEB-BASED GIS
CASE
STUDY AT TELUK CENDRAWASIH MARINE NATIONAL PARK, INDONESIA
Juniawan
Priyono, Prof. Dr. Dulbahri
Faculty
of Geography Gadjah Mada University, Yogyakarta, Indonesia
Coral
reef ecosystem at Teluk Cendrawasih Marine National Park, Papua, Indonesia has
inside very
big
potential resources, unfortunately its exploitation bring about damaged. The
exploitation and
development
need more planning in an integrated manner, with rationally coral reef
management.
Former
step in this management system is developing coral reef spatial database in
digital format that
rounds
up its existing, distribution, wide area, conditions, type, and its species.
Coral reef data that
having
spatial and temporal references need a system for collecting, storing, and
management.
Geographic
Information System (GIS) as a computer-based system with four capabilities to
handle
geographical
reference data, i.e. entering, data management, manipulating and analyzing,
along with
output;
most appropriate to apply. GIS product also could be published on World Wide
Web that can
be
accessed by everyone in everywhere through internet browser.
The
development of coral reef spatial database, with Web-based GIS (Geographic
Information
System)
application, rounds up activity: (1) Digital mapping of area restriction and
management
zones
are carried out over digitizing, editing, UTM transformation, tabulation of
attribute data, and
map’s
layout process; (2) Coral reef condition mapping is carried out by image
processing of Landsat
Thematic
Mapper base on Lyzenga’s algorithm application. Field surveys for classify
determining
are
carried out base on line intercept transect (LIT) method for remote sensing
purpose; (3) Coral
tabular
database in digital format is arranged base on US Fish & Wildlife Service
Division of Law
Enforcement
(1991) and Australian Institute of Marine Science (1994) standard; (4) Web
pages are
taken
for relate on map and tabular database in an interactive manner with internet
mapping software
and
to publish database on internet.
The
result of this research can be accessed pass through :
http://www.wwf.or.id/
sahul/tcmnp/mapdb/coralmap.asp.Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
77
INHERITED
ASPECTS OF MODERN BARRIER REEF MORPHOLOGY
Edward
G. Purdy, Edward L. Winterer
Foxbourne,
Hamm Court
Weybridge,
Surrey KT13 8YA, UK
The
Darwinian model for the successive evolution of fringing reefs, barrier reefs
and atolls with
progressive
subsidence has been generally accepted following the indisputable proof of
subsidence
provided
by drilling results on Pacific atolls. Nonetheless, there is no proof that
subsidence ever
produced
such a genetic succession of reef types. Instead, there are data that don’t fit
the
expectations
of the model, such as the similar lagoon depths of barrier reefs and atolls as
opposed to
the
subsidence theory’s prediction that atolls should have significantly greater
depths.
As in
the case with atolls, the maximum lagoon depth of 69 modern barrier reefs is
statistically
correlated
with the lagoon catchment area for modern rainfall. Present day, low latitude,
oceanic
rainfall
patterns would seem to be an appropriate proxy for relative geographic
differences in glacial
lowstand
rainfall, even though the absolute amounts of rainfall are unknown.
Consequently, the
correlation
suggests the importance of Pleistocene subaerial solution in contributing to
barrier reef
morphology.
Further support for antecedent influence occurs in the form of barrier reef
passes in
which
the depth of the reef pass is correlated with onshore drainage volumes. Choked
or partially
blocked
reef passes seem likely to represent breaching of a pre-existing drainage
divide that
separated
seaward from lagoonward directed meteoric drainage during glacial low stands of
sea level.
The
role of carbonate deposition in contributing to lagoon morphology relates to
lateral infilling of
the
lagoon by rim-derived sediment and the vertical accentuation of antecedent
relief. In at least one
instance
bilateral progradation in both a seaward and lagoonward direction can be
demonstrated.
Resulting
barrier reef morphology reflects the alternating consequences of Pleistocene
fluctuations in
sea
level. During sea level rise, there is an accentuation of antecedent relief
followed by highstand
progradational
infilling of the lagoon by rim-derived sediment. During lowstands the infilling
is
terminated
and the lagoonward facing infilled edge is eroded, commensurate with the
development of
solution
morphology on the subaerially exposed carbonates. The consequences of the
numerous
Pleistocene
and perhaps earlier fluctuations of sea level are the barrier reef morphologies
that we see
today..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
78
CLASSIFICATION,
ACCURACY ASSESSMENT AND UTILITY OF REEF-TOP BENTHIC
HABITAT
MAPS DERIVED FROM LANDSAT DATA OF THE EGYPTIAN RED SEA
Samuel
Purkis, Jeroen Kenter
Dept.
Sedimentology
Faculty
of Earth and Life Science
Vrije
Universiteit
De
Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
purs@geo.vu.nl
Presented
is a technique to monitor benthic assemblages on the fringing coral reef tops
of the central
Egyptian
Red Sea using Landsat TM imagery calibrated by field measurement. Above water
spectral
reflectance
measurements of reef top substrates were made on a section of reef top
surrounding
Marsa
Shagra using an OceanOptics spectrometer. An analytical model was formulated
and proven
capable
of removing the influence of a water column of known thickness from an above
water
measurement
provided that values for the water’s inherent optical properties were
available. Both the
field
spectra and atmospherically corrected TM image were corrected for the influence
of the
intervening
water column using the model to retrieve values of substrate reflectance.
Unlike the field
spectra,
depth was not known for every pixel in the satellite imagery, as ancillary
bathymetric data
for
the area was not available. Instead, a simple generic model of reef topography
and in situ tidal
measurements
were combined to provide an estimate of depth. The processed field spectra were
assembled
into 7 classes representing the dominant substrate assemblages present on the
reef top and
resampled
to the bandwidths and sensitivity of the 3 visible bands of Landsat TM. Image
classification
was afforded using a maximum likelihood method based on a normal probability
density
function. Each image pixel was assigned to the substrate class to which the
probability of
membership
was greatest based on the covariance distribution of the field spectra.
Accuracy
assessment
of the resulting benthic habitat maps was performed against 87.3 km˛ of
metre-scale
ground-truth
data using both Kappa and Tau coefficients calculated from standard error
matrices. In
areas
where bathymetry was absent, classification accuracy was calculated to be 47%
higher than
would
be expected through chance agreement. In the limited areas where bathymetry was
known,
classification
was found to be significantly (P=0.01) more accurate and over 70% better than
chance.
The
work indicates that in areas where bathymetry data is absent, but predictable
using a simple
topographic
model, Landsat TM can be used to resolve both the geographic extent and
geomorphological
and ecological zonation of the reef top at a regional scale. In areas where an
independent
measure of bathymetry is available, it is shown that benthic habitat
distribution can be
predicted
with a high degree of accuracy and that quantitative analysis is possible. As
differentiation
between
optically similar substrates such as seagrass and green algae is displayed, the
detection of
community
phase-shifts of such classes can be used as a sensitive proxy for environmental
stress.
Landsat
offers a 25 year archive of imagery with which to investigate the seasonal,
annual and
decadal
dynamics of the reef-top. Such information is valuable to quantify the temporal
dynamics of
carbonate
depositional environments, as well as the impact of construction and habitat
alteration
related
to tourism development in the area. The results highlight the utility of
spaceborne remote
sensing
techniques to monitor short-term events in real time that could not be tackled
through in situ
survey
for logistical reasons..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
79
SPATIAL
AND TEMPORAL VARIABILITY OF
CORAL
COMMUNITY DYNAMICS IN THE RED SEA
Götz
B. Reinicke, Helmut Schuhmacher
German
Oceanographic Museum
Katharinenberg
14/20, D-18439 Stralsund, Germany
Goetz.Reinicke@meeresmuseum.de
Coral
reef benthic community structures reflect the temporal integration of species
specific
ecological
demands over prevailing environmental conditions. Dynamic processes, such as
recruitment,
colony fragmentation, growth and retreat or mortality, however, create
within-community
fluctuations
in composition and abundance on the species level. The quantification of the
natural
„noise“ in community dynamics is essential for the status evaluation of recent
coral reefs and
coral
community recovery (succession) after natural perturbations or anthropogenic
disturbances.
Repetitive
surveys of test squares (25 m˛) were used to estimate rates of species and area
turnover in
the
living benthic coverage. Four pristine reef sites (wind- and leeward outer reef
and lagoon slopes
respectively,
all at 10-12 m depth) at the Sanganeb-Atoll/Sudan were first mapped in 1980
(Mergner
H
& Schuhmacher H 1985 Helgol Meeresunters 39: 375). Resurveyed in 1991, the
data analysis
revealed
relative species turnover values (Trel,
Schoener TW 1983 Oikos 41: 372) ranging 1.97-3.24
%yr -1 (median 2.67 %yr -1
). They largely agree with values calculated from transect data of
Caribbean
coral
communities: 2.28 ± 1.04 %yr -1 , n=21
(Carysfort Reef, Florida, Dus tan P & Halas JC 1987
Coral
Reefs 6: 91).
Rates
of areas colonised or cleared by new or disappearing species during the census
interval were
used
to estimate areal turnover periods of living coral communities: the overall
recruitment periods
calculated
from newly recruited species in the test areas (median 416 ys, ranging 323-755
ys)
exceeded
the overall clearing periods calculated from disappearing species (median 342
ys, ranging
312-527
ys). Assuming a balanced overall area budget of colonising and clearing
processes (with
rather
stable ratios of unoccupied substrate, Sheppard CRC 1985 Mar Ecol Prog Ser 25:
259) the
difference
most likely is compensated for by recruitment and vegetative propagation of
persistent
species.
Comparison
with a coastal fringing reef near Aqaba/Jordan (Gulf of Aqaba, test square
first mapped
in
1976, by Mergner H & Schuhmacher H 1981 Helgol Meeresunters 34: 115)
revealed significant
differences
in community turnover parameters. Different clearing rates during two census
intervals of
6 and
7 ys resulted in a high value for Trel (4.3
%yr -1 ) during the first interval with a
subsequent
period
of increased recruitment. Calculated periods of overall area turnover (205 ys
for species
recruitment,
22 ys (!) for clearing) lay well below the reference values from the central
Red Sea and
appear
to reflect onshore anthropogenic impact.
Results
demonstrate the relevant time scale of several hundreds of years for coral
community
development
and highlight their vulnerability to short term impacts.
This
study was supported by the Deutsche Forschungsgemeinschaft (Schu 75/13).Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
80
CHARACTERIZATION
OF SUPEROXIDE DISMUTASES IN SYMBIOTIC
ANTHOZOANS
Sophie
Richier 1 , Pierre -Laurent Merle 1 , Paola Furla 1 , Francois Sola 1 ,
Denis Allemand 1,2
1 UMR UNSA-INRA 1112, Faculte de Science,
Universite de Nice-Sophia Antipolis, BP71, F-06108
Nice
Cedex 02, France
2 Centre Scientifique de Monaco, Avenue
St-Martin, MC-98000 Monaco, Monaco
Plants
have acquired, through their evolution, defense mechanisms against oxidative
stress, which
mainly
act against ROS generated consequently to the photosynthetic O2 production. Such a ROS
production
is however not limited to plants but also to some animals living in symbiosis
with
chlorophyllian
organisms. One of the best-known symbiotic systems is the phototrophic
association
between
Cnidarians and Dinoflagellates (Symbiodinium sp. known as zooxanthella).
Among these,
hermatypic
Scleractinian corals and sea-anemones are largely distributed in the oceans.
The aim of
the
present study is to characterize the first enzyme involved in the cellular
oxidative defenses, the
superoxide
dismutase (SOD), in a Mediterranean sea anemone (Anemonia viridis) and
in a
hermatypic
coral (Stylophora pistillata). During oxidative stress conditions, the
SOD act by
dismutating
O2° - in
H2O2, which
is subsequently transformed in H2O and O2 by another enzyme, the
catalase.
First results have confirmed the presence of coelenteric oxygen variations in a
tentacle of the
sea
anemone, with a hyperoxia state during the daytime (60 % of dissolved O2) and an anoxia state
during
the night-time. The isozymes of Cnidarian SOD were visualized on native
polyacrylamide gel
and
the specific activities were measured by spectrophotometry. In Anemonia
viridis, three classes of
SOD
have been identified using specific inhibitors. They differ from each other by
the metallic co-factor
(Cu/Zn-SOD,
Mn-SOD and Fe-SOD) and tissue-specific isozymes have also been shown for
each
class. An active Cu/Zn-SOD isozyme was restricted to animal compartment
(ectodermal and
endodermal
cells), although an inactive one was localized by Western Blot in the
zooxanthellae. Four
Mn-SOD
isozymes were distributed among symbiotic partners. One of those was common to
both
Cnidarian
and zooxanthella cells and located in the mitochondrial compartment, three
others were
restricted
to endodermal cells and to the zooxanthellae. Finally, two Fe-SOD are located
not only in
the
zooxanthella compartment but also in the endodermal cells. The apparent
molecular weight
(MWapp) and isoelectric point (pI) were determined
for each isozyme. Analysis of the Stylophora
pistillata
SOD isozymes shows a different pattern of the electrophoretypes, which
suggests a species-specificity
of
the SOD isozymes. Nevertheless, S. pistillata presents also at least 7
isozymes with
three
main electrophoretypes having pharmacological Mn-SOD characteristics. The
presence of high
isozyme
diversity, typical to photosynthetic organism, is supposed to be involved in
the extraordinary
adaptation
of the symbiotic Cnidarians to oxygen variations..Oral
Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
81
EXTREME
CLIMATIC EVENTS AND HIGH-LATITUDE REEF-BUILDING: WHAT
CONSEQUENCES
FROM GLOBAL CLIMATIC CHANGE?
Bernhard
Riegl
National
Coral Reef Institute, Nova Southeastern University Oceanographic Center,
8000
N. Ocean Drive, Dania FL 33004, USA
Particularly
in high latitudes (and on reefs in extreme settings) reef-building by in
situ framework
production
is strongly influenced by extreme climatic events that can cause coral mass
mortality.
Subsequent
break- up of coral skeletons and heavy bioerosion remove the framework and can
thus
lead
to a reef switch-off. Examples of such events are sea-surface-temperature
anomalies, frequently
associated
with ENSO events, and extreme-wave-energy events frequently associated with
tropical
cyclones
(hurricanes). For a series of high- latitude coral areas (Florida, South
Africa, Red Sea,
Arabian
Gulf) in comparison with some tropical reef areas (Indonesia, Cayman, USVI) the
effects of
climatic
teleconnections in the predicted global warming scenarios is explored. Factors
examined for
possible
importance for high- latitude reef building processes are: increase in
frequency of ENSO and
teleconnected
events, latitudinal changes in the tropical cyclone (hurricane) belts. Also
warm-water
delivery
into the South Atlantic via Agulhas rings and the North Atlantic thermohaline
circulation as
well
as the possible link between increased SST and emergent diseases is briefly
revisited..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
82
REEF
MANAGEMENT IN THE 21 ST CENTURY:
EFFECTIVE MONITORING AND
LEGISLATIVE
GUIDELINES FOR LAND-BASED SOURCES
Michael
J. Risk
School
of Geology and Geography,
McMaster
Univ. Hamilton ON Canada, L8S 4M1
Despite
recent emphasis on the effect of “global change” on reefs, the evidence of
relative impacts is
quite
clear: the world’s coral reefs have already suffered widespread damage.
Managing this decline
will
require effective community-based monitoring, coupled with objective criteria
by which
discharges
from the land may be regulated. The first criterion in MPA location should be
distance
from
land-based sources.
Virtually
every monitoring protocol uses some variant of the line transect method (Risk,
1972), with
video
records scored by trained biologists. These efforts are technology- intensive,
require
taxonomically-trained
personnel, and are inappropriate for Third World settings (where most of the
reefs
are). In addition, almost all of them fail to include several critical aspects
of reef health, such as
bioerosion.
This is a particularly serious oversight, as bioerosion rates increase in
lockstep with
coastal
eutrophication. We should therefore abandon traditional monitoring, in favour
of
bioindicator-based
methods that can be used by untrained people. These “early warning” indicators
can
then be policy triggers linked to programs to identify and quantify sources of
stress.
Community-based
monitoring using stomatopods is very effective in Indonesia: village women are
trained
to classify and count these organisms as they glean for food at low tide
(Erdmann’s work).
Kate
Holmes and co-workers, in both the Caribbean and Indo-Pacific, have
demonstrated that local
people
can quickly be trained to assess extent of bioerosion in coral rubble. The
method is quick,
cheap,
and can be linked directly to coastal contamination levels. Whatever method the
local
community
uses, there needs to be a level of change that triggers a policy response.
The
major anthropogenic stresses on reefs are sedimentation, sewage, industrial
discharge and
fishing.
Inappropriate fishing techniques (blast- fishing, cyanide, muro-ami) are a
problem worldwide,
are
always “illegal”, and hence require effective application of existing policies
rather than enactment
of
new legislation. In regions where the bulk of incoming sediments are
siliciclastic, sediment stress
may
be cheaply and quickly assessed by determining insoluble residues of coral
samples. In general,
residues
exceeding 0.2% signal stress, and this can be the trigger level to involve
policy measures.
Reef
growth is clearly inhibited at SPM values >10 mg per litre; where these
values occur, mitigation
may
include watershed reforestation and modification of agricultural practices.
Sewage stress will be
detected
by bioerosion bioindicators, and the levels assessed via analysis of d 15 N in coral tissue. For
legislative
purposes, an increase of 2 per mil over time on any given reef, or between
affected and
comparison
reefs, can trigger policy intervent ions such as sewage treatment plants.
Assessment of the
relative
impacts of sediments and sewage costs about $300 per reef.
Although
trigger levels for industrial discharge levels have not been worked out, corals
themselves
can
serve as monitors. Levels of heavy metals and POP’s can be determined over
time, via analysis
of
coral and gorgonian skeletons. Once water/coral partition coefficients have
been determined,
corals
can be used to determine safe levels for human habitation..Oral Presentation
Abstracts Volume
International Society for Reef Studies
European Meeting – Cambridge, 4-7 th September,
2002
83
MONITORING
ENVIRONMENTAL VARIABILITY AROUND COLD-WATER CORAL
REEFS
USING A BENTHIC PHOTO LANDER
JM
Roberts, OC Peppe, DJ Mercer, JD Gage, DT Meldrum
Scottish
Association for Marine Science
Dunstaffnage
Marine Laboratory, Oban, Argyll, PA37 1QA, UK
Current
estimates of the environmental sensitivity of cold-water corals and their
associated biota are
limited
by our incomplete understanding of the variability of the cold-water coral reef
environment.
The
sensitivity of reef biota to sedimentation and resuspension events is largely
unknown and the
influence
of seasonal phytodetrital deposition has not been studied in situ. Here
we describe the use
of a
benthic photo lander to monitor this variability by the Sula Ridge reef complex
on the mid-Norwegian
continental
shelf. The photo lander provides a platform for time- lapse digital and film
cameras
to image the seabed while the optical characteristics (light transmission,
backscatter and
fluorescence)
of the seawater and the current regime are recorded. At a water depth of 280m,
the
photo
lander recorded a dynamic environment with a tidal current regime and mean
estimates of
sediment
resuspension 0.5m above the bed of 136µg/l (maximum 771µg/l) over a four day
period.
Initial
analysis of the seabed photographs shows intense feeding activity of echiuran
worms
(probably
Bonellia viridis) pointing to rapid bioturbation of the sediment around
the reef areas. Only
with
longer term monitoring of cold-water coral reef environments in situ can
informed inferences
about their environmental sensitivity and eventual management be