Fishermen call it the "Hell Hole," this place of whistling winds and smashing waves in the north Atlantic Ocean. Above a chasm in the Northeast Channel, which runs between the submerged Georges and Browns banks off Nova Scotia, fishermen catch cod, haddock and other fish with hooks at the ends of long lines, and by dragging nets along the sea floor. "It takes guts to fish 'Hell Hole,' " said Sanford Atwood, a 54-year-old Nova Scotia fisherman who has braved Hell Hole's elements aboard his boat, the Ocean Legend. "But the risks are worth the rewards. Whenever I'm out there, I come back with a boat loaded with fish. It's 'trees' on the bottom of the sea that are providing this bounty." In "Twenty Thousand Leagues Under the Sea," Jules Verne wrote of a forest of coral hidden from human eyes in the depths of the ocean. Although Verne couldn't have known that Hell Hole and other places like it existed, his century-old novel of undersea derring-do presaged a discovery made only recently by fishermen and scientists. Deep-sea corals -- fishermen call them "trees" -- line undersea canyons and dot the "peaks" or edges of fishing banks, where currents in steep-sided channels carry food to the corals. And where there are deep corals, it turns out, there are fish in abundance. "Some of us are beginning to worry, though," said Atwood, "that fishermen using bottom-dragging gear are knocking over all the 'trees.' If that continues to happen, [what will happen to] all those fish? They'll be gone." When most people think of coral, they think of the reefs of Hawaii or the Caribbean. But cold waters have their own wonders. Extensive stands of deep-sea corals now have been found off Nova Scotia, Maine, Alaska, Scotland, Ireland and Norway. Unlike tropical-sea corals, which depend for sustenance on algae called zooxanthellae that live within their bodies, deep, cold-water corals are suspension feeders: they attach themselves to the ocean bottom and feed off tiny animals floating by. Corals in Atlantic Ocean depths are solitary, nonreef-forming entities, mostly scleractinians (stony corals) or gorgonaceans (branching, horny corals, such as sea fans). As a result of their cold, dark environment, these corals have much slower growth rates than shallow, tropical corals. Anthony Grehan, a deep-sea biologist at the Martin Ryan Marine Science Institute in Galway, Ireland, found that deep corals grow just an inch or two a year, making many of the individual "trees" brought up by fishermen hundreds to thousands of years old. "Unlike shallow-water corals, these corals add yearly rings [similar to the rings formed by trees on land] for hundreds of years," said David B. Scott, a geologist at Dalhousie University in Halifax, Nova Scotia, "making it possible to get a 'tape-recording' of information about the ocean over centuries to millennia." To fishermen, deep corals also provide knowledge about where particular fish can be found. "When you're over strawberries [a red coral named Gersemia rubiformis]," said Atwood, "you set your gear for haddock. Bubblegum tree [Paragorgia arborea], which can grow to several feet high, is great for cod and halibut." Fishermen say that the pink bubblegum tree is the biggest of the deep corals. One long-liner brought in a huge piece, about 20 feet long and a foot in diameter. "I had to cut it apart with a fire ax to get it off the boat," the fishermen remembered. "And the halibut where we found it were everywhere." Scientists conducting research on deep corals have found that the claims made by Atwood and other fishermen are indeed true. Biologist Martin Willison at Dalhousie University was "really surprised by all this at first. I'd thought corals were only tropical things." But seeing is believing. "After I visited a street-side display of deep corals set up by fishers who had brought them to the surface, I soon found otherwise. It turns out that the complex habitats provided by these corals are important in protecting juvenile fish . . . in various fisheries. The destruction and removal of these corals will have an effect on the food supply available to commercial fish species. What we don't yet know is: How much?" | | Coral tree Nearly 20 years ago, Atwood walked into a Canada Department of Fisheries and Oceans (DFO) office with a large piece of deep coral he had towed in on a long-line. He showed it to a DFO official, and asked whether agency scientists knew that draggers were destroying beds of the coral off Nova Scotia so they could more easily tow their gear along the bottom. And so the saga of the deep corals began, said Derek Jones, a long-line fisherman and founder of the Canadian Ocean Habitat Protection Society (COHPS), a deep-coral conservation group in Halifax. "Atwood tried to tell them at DFO that draggers sometimes lowered chains between two boats and ran the chains through stands of coral to get rid of it. The draggers called it 'trimming the trees.' I don't think DFO believed all this about underwater 'trees' maybe being fish havens, until they went out and looked at these corals for themselves." No one had seen deep corals in place to find out whether they were in fact good fish habitat. Then in the summer of 2001, a group of Canadian government and university researchers used a remotely operated underwater vehicle to explore the sea-floor in the Northeast Channel. The mouth of the channel, said scientist Mark Butler of the Ecology Action Centre in Halifax, "is a major location for deep corals, because large boulders provide something for the corals to attach to, and strong currents carry food there. 'Trees' in profusion are attached to these huge rocks." Results of the expedition made believers out of DFO scientists and fisheries managers, said Mike Sinclair, regional director of science at DFO's Bedford Institute of Oceanography. "While we continue to study the region off Nova Scotia to find out where, exactly, the deep coral areas are and what species live there, we're looking into setting aside some of these locations as protected areas." In June, the Canadian government banned all fishing in an area off southern Nova Scotia to protect the deep corals there. DFO closed about 90 percent of a 263-square-mile area in the Northeast Channel to all bottom-fishing gear. Long-line fishermen are allowed on an authorized-only basis in the remaining 10 percent of the protected area. The affected region, called the Coral Conservation Area, is part of DFO's ground fish management plan for Georges Bank. "This closure will allow us to study the impact fishing has had on several species of deep corals," Sinclair said. Butler called the designation "a first step in the right direction," and he hopes for fishing closures in other coral areas. To long-line fishermen, however, the move is bittersweet, Atwood said. "Although we worked hard to get DFO to do this, we're being penalized the most -- our gear does the least damage to the ocean bottom. That being said, though, my view is that we've taken from the ocean for years. Since we now know that deep corals are all over some parts of the sea floor, I think it's time we gave something back and found out just how important these corals are to the fish and to us." 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