Coral fixation: Can we grow these Caribbean reefs on a farm? (Bequia Island, St. Vincent and The Grenadines) Photo copyright: iStockphoto.com/Dennis Sabo
Reversing Reef Grief
By Kirk Fernandes
Martha Campbell leans over a large concrete tub filled with a forest of grayish-green undulation. “This is our most popular item,” she says, pointing to hundreds of inch-high Pulsing Xenia, a soft tree-like coral with tentacles that open up like petals on a time-lapsed flower. Only these “flowers” can’t decide whether to stay open or closed; they blink feverishly at rapid intervals. The aquarium hobbyists like the movement, she explains.
Campbell is a salt-water breeding specialist for Aquatica Tropicals, a Florida-based producer of fish and live coral for home aquariums. For the last five years, she’s cultivated nearly a dozen species of Indo-Pacific coral in a land-based facility, instead of in the ocean. She often makes up the techniques as she goes along. “There’s no how-to handbook out there for raising corals,” she says.
While such coral farms certainly have commercial promise, many scientists see them as valuable tools that can be used to help restore disappearing coral colonies. The nascent field of land-based coral propagation has blossomed in the last decade, largely due to increasing concerns about the health of the world’s reefs. Earlier this month the U.S. Coral Reef Task Force called for more public awareness and education regarding the problem, citing reports that two-thirds of Caribbean reefs are considered “significantly degraded” by disease, warm-water bleaching events, and human interaction, among other causes.
Restoration projects are already underway. The Florida Aquarium, University of Florida and several government agencies have been growing seven species of Caribbean corals from fragments recovered at a Key West harbor construction site. Like cuttings from a tree, the coral fragments can develop into new parent colonies, provided they have a steady, clean flow of water and sunlight. The fragments are glued to concrete plates and reared over a period of six months or longer. On Dec. 4-8, researchers are scheduled to plant more than a hundred coral-seeded discs at Western Sambo reef in Key West, where ship groundings have damaged coral colonies.
In addition to developing techniques for propagation, the scientists are trying to gauge how well the cultured corals will fare in the wild. An earlier planting in May showed promise when the site was revisited in August, although one species with a brain-like appearance – Diploria clivosa – appeared to be struggling, says Dr. Ilze Berzins, the Aquarium’s project manager.
The other purpose of the research is to develop a system that ensures cultured corals don’t introduce potential disease into the natural ecosystems. “One of the things we’ve been working on is trying to minimize or remove that fear,” says Berzins. She and the other researchers are developing a health certification process to ensure only the best, bacteria-free candidates are used to seed reefs.
With adequate funding available, Berzins sees the potential for emergency coral nurseries patterned after mangrove restoration initiatives. “The future dream is you call up a nursery and say, hey I need a hundred pounds of palmata.” (In June 2006, Acropora palmata became the first coral species, along with A. cervicornis, to be designated as “threatened” under the Endangered Species Act.)
Others have attempted to grow coral from earlier stages. Alina Szmant, a professor at the University of North Carolina-Wilmington, has spent the last six years capturing samples of sperm and eggs during annual coral spawning events. She rears the resulting larvae for four to eight days, until they’re old enough to potentially attach themselves to a solid base for growth. It’s already painstaking work, but such efforts haven’t been easy as of late for another reason. “We had two years in a row where we had hurricane after hurricane,” says Szmant, who’s seen the storms annihilate burgeoning coral colonies and alter spawning patterns.
Though hurricanes are an unyielding force, there are causes of reef decline that can be controlled, such as over-fishing and pollution. “If we can resolve some of the problems that have affected the adult coral population, then we can probably do more restoration good,” says Szmant. Until these larger issues are addressed, coral farming can only temporarily hold back the tide of coral extinction.