From Balls of Concrete
|Designer reefs made from concrete balls help replace and support natural ones as overfishing, pollutants and disease take a toll on vital ecosystems. WSJ's Guatam Naik reports.|
But copying Mother Nature isn't easy. An artificial reef may work in one location but flop elsewhere. Some coral fragments thrive only in shallower waters. Others must be oriented just so or they won't grow. On the Caribbean island of Curacao, a reef-ball team made the mistake of planting corals upright instead of sideways, and they fell off in a big storm. In Oman, which isn't known for hurricanes, a storm earlier this year wiped out some coral growth on reef balls.
Reefs that develop naturally are created from colonies of tiny coral polyps. When these animals die, they leave behind a limestone "skeleton" on which other polyps grow, slowly creating larger and larger structures. These reefs range from the size of a small flower bed to the Great Barrier Reef, a coral edifice that stretches 1,400 miles along the Australian coast.
Sea creatures depend on reefs for shelter and feeding and mating grounds. For humans, they are a rich source of fish and, increasingly, a destination for snorkeling, diving and other recreational activities. The U.S. National Oceanic and Atmospheric Administration estimates that coral reefs world-wide provide as much as $375 billion of services annually.
|Shown at low tide, the breakwater helps reduce beach erosion.|
But reefs face increasing danger as traditional threats are compounded by the effects of global warming. Higher sea temperatures have weakened or killed a large number of coral reefs through a process known as bleaching. Warmer oceans may also be triggering more frequent intense hurricanes, and a single such storm can trash parts of a 10,000-year-old reef in minutes. In addition, as more carbon dioxide is pumped into the air, more gets dissolved in the oceans -- turning the water more acidic and hurting coral growth.
"About 30% of the world's reefs have been destroyed in my lifetime," says the 43-year-old Mr. Barber. If current conditions continue, as many as 70% of the world's reefs could disappear within 50 years, according to NOAA.
In Mexico, authorities from the National Marine Park off Cancun are relying on Mr. Barber's expertise to safeguard their reefs, which have been damaged by boat groundings, powerful hurricanes and a crush of tourists. Many snorkelers, for example, are nowadays dispatched to artificial reefs with terrestrial pedigrees instead of those that sprouted from sea beds. "The natural reefs need to rest," says Jaime Gonzalez Cano, director of the Cancun marine park, who estimates 600,000 snorkelers and divers visit the area every year.
Molded from concrete, a reef ball can be as small as a basketball or as large as a car. An inflatable bladder placed in its hollow center allows the ball to float, making it easy to transport and maneuver in the water. Fragments of living coral are glued to the surface of the ball, which is then submerged. If all goes well, the coral grows and eventually attracts fish and other marine life.
|Rescued corals growing|
Mr. Barber's team and the Mexican authorities have placed reef balls in three locations near Cancun. During a dive at one of the sites, Mr. Barber pointed out several reef balls that had been planted with coral fragments a month earlier. The balls still had little growth, looking more like huge, abandoned Wiffle balls than anything Jacques Cousteau might have happened on.
At the second location, where 100 balls were placed in 2004, large sea fans waved in the current and tropical fish darted through the reef's hollows. But even artificial structures are vulnerable: When Hurricane Dean hit Mexico in August, it tore a lot of soft growth, including colorful sponges and barnacles, from the reef balls.
The reef balls at the third site, 30 feet down, weren't planted with coral fragments. Instead, in a decade's time, coral, sponges and other organisms sprouted spontaneously on the concrete surfaces and attracted a multitude of fish. When one of the divers brushed aside some sea grass to get a better photograph of a moray eel, the frightened creature slithered from its cranny and lunged at him. "It almost got my hand," said the diver, who was equally startled.
Mr. Barber got interested in restoring coral reefs in 1988, when a hurricane wiped out a Cayman Islands reef he first visited as a teenager. Sitting on the beach with his dad, he wondered what would happen if a beach ball plastered with concrete was rolled onto the ocean floor. Would coral eventually sprout on its surface?
Early experiments suggested it would. So Mr. Barber quit his lucrative job as a consultant at Towers Perrin and put $50,000 of his savings toward making reef balls. In 1996, Mr. Barber turned his company into a nonprofit, publicly audited foundation, figuring that would lead governments -- some of his biggest clients -- to trust it more. The group has coral experts and volunteers who install reef balls all over the world.
Others have licensed the technology. Eternal Reefs Inc., of Decatur, Ga., charges as much as $6,500 to put a person's cremated remains into a reef ball. (It asks less for animal burials.) The Reef Ball Foundation gets part of the revenue and has final say about where the balls will be placed.
Mr. Barber says his foundation, based in Athens, Ga., will oversee the installation of 100,000 reef balls this year, double the number in 2006. It costs an average of $500 to make and install a single reef ball. There are now 550,000 in waters around the world. The president of the United Arab Emirates has them fringing an island he owns.
Says Mr. Barber: "We're trying to keep up with global warming" and other factors that imperil reefs. "You've got to be an optimist and keep plugging on."
Write to Gautam Naik at firstname.lastname@example.org