Stocking aquariums might be endangering Florida's reefs

Stocking aquariums with marine life is becoming profitable; but despite care used by divers, it could be costly for our reefs

David FleshlerSunSentinel.com 24 Nov 08;

At a depth of 95 feet, in a silent world illuminated in shades of dark violet, Jeff Turner takes a net in each hand and begins to hunt. Gliding along the ocean floor, he snares a Cuban hogfish, a rock beauty fish and several sponges.

He takes half an hour to bring the fish to the surface and uses a hypodermic needle to extract air from their swim bladders, preventing them from bursting in the unfamiliar low-pressure environment. Like a bounty hunter — and unlike the typical commercial fisherman — he wants his quarry alive.

Turner, who lives in Parkland and operates a high-end aquarium design business, is one of about 130 highly skilled divers whocomb the reefs of southeastern Florida to supply pet stores and aquarium hobbyists with tropical fish, undersea plants and other forms of marine life. But the business has changed in ways that some scientists fear could threaten the reefs, despite the care exercised by divers.

With the growing popularity of living reef aquariums, divers have begun going after the unglamorous crabs, snails and other invertebrates that eat algae, consume dead things and filter water. Scientists, state wildlife officials and many of the divers worry that the removal of vast numbers of these species for home aquariums could upset the ecology of Florida's reefs.

"There has been a change in consumer demand," said Jessica McCawley, a biologist with the Florida Fish and Wildlife Conservation Commission. "People used to just keep a fish in a tank with some dead coral. They want invertebrates now, especially the cleanup crew: snails, crabs."

The invertebrate catch for the aquarium trade has risen steadily, with divers landing 117,889 crabs in 1994, for example, compared with 1.8 million this year.

The commission will consider quotas for several of these species at its meeting Dec. 4 in Key West. Worked out in consultation with people in the business, the rules would set bag limits for a variety of species, for example, establishing trip limits of 400 emerald crabs, 2 gallons of the snail Lithopoma tectum and 200 Condylactis anemones.Turner, one of the divers advising the commission, said limits were important to protect the reefs as the market changes.

"The proposals for invertebrates are needed," he said. "There's a whole set of new species being listed, and this is essential for conservation."

But the state's limits may not be enough to protect the reefs, said Andrew Rhyne, a biologist at Roger Williams University in Rhode Island and the New England Aquarium who has studied the Florida aquarium dive business.

"What scares me is we don't know anything about the effect of removing 2 1/2 million hermit crabs from their habitat," he said.

"There might not be any effect. But you don't know. The emerald crabs are scraping the bottoms of the corals and keep the algae off them. Now will these corals live without the crabs?"

He said there's a lack of scientific research behind the rules and insufficient ability to enforce them.

"If you remove the emerald crabs from the system, will it collapse?" he asked. "We don't know. You all are doing a very large-scale experiment."

Diving to supply home aquariums can be a lucrative business, with the limited number of state-issued licenses fetching up to $30,000 on the open market. The aquarium divers concentrate on the reefs that run from Martin County to the Keys. Several divers interviewed said the proposed restrictions would not cost them too much business and they support the restrictions in order to protect the reefs.

"We don't want to eliminate any of these species," said Bill Parks, a diver in Boynton Beach. "We want them there for people to see. We're dealing with a fishery where most species are not migratory. If you go into an area and fish them, we need to let them recover."

Clay Jackson, editor of Freshwater and Marine Aquarium magazine, said the vast majority of saltwater fish and invertebrates sold in pet stores are caught in the wild because, unlike freshwater species, they're difficult to farm. As hobbyists have become more sophisticated and technology has improved, he said many people rely on species caught in the wild to create aquariums that reproduce highly specific ecosystems, such as a Caribbean rubble zone or tropical seagrass.

"I think the state of Florida is doing the right thing," he said. "These invertebrates are becoming more and more popular. You get them in your tank, and they don't live forever.... I don't think there's a problem at this point, but they're putting these in place so it won't become a problem in the future."

Photographer Carey Wagner contributed to this report.