Dr. Rob Dillon, Coordinator

Monday, May 9, 2005

Ivory-billed Freshwater Gastropods

Congratulations are in order for our colleagues Jeff Garner of the Alabama DCNR and Stephanie Clark of the University of Alabama! Last week The Nature Conservancy announced that both researchers have recently rediscovered freshwater gastropods previously feared extinct. An article from The Birmingham News is appended below.

Jeff collected Goniobasis vanuxemiana and G. lachryma diving in the Coosa River below the Logan Martin Dam east of Birmingham. Stephanie found Clappia cahabensis in the Cahaba River south of Birmingham, closer to Tuscaloosa. Their discoveries were unrelated but highly coincidental - both occurred last year and were reported independently at the annual Alabama Mollusk Meeting. TNC's decision to issue a combined press release last week was prompted by the big Ivory-billed Woodpecker buzz.

Good job to all involved!

------[The Birmingham News 3May05]-----------

Biologist, student find 3 snails thought to have been extinct
Coosa, Cahaba Rivers turn up prizes the discovery of snails believed to have been wiped out by human actions
Tuesday, May 03, 2005
Birmingham News staff writer

Three snails listed as extinct have been rediscovered in Alabama's rivers, the Nature Conservancy plans to announce today.

Jeff Garner, the Alabama Department of Conservation and Natural Resources' mollusk biologist, rediscovered the cobble elimia and the nodulose Coosa River snail on a stretch of the Coosa that remains free-flowing between Lake Logan Martin and Neely Henry Lake. And Stephanie Clark, a postdoctoral student from Australia, found a Cahaba pebblesnail in the Cahaba River in Bibb County.

Alabama is recognized as the globe's most densely populated home of mollusks - the snails and mussels that dot the beds of rivers, the acres of white shells that gave Muscle Shoals its name. The state also is known to be the nation's top spot for extinct and imperiled mollusks. Of 174 species of aquatic snails to occur here, 39 are presumed to be extinct.

The Coosa River is home to hundreds of aquatic animals, making it a global hot spot for snails and mussels. For that reason, it also has a more lethal distinction - the site of the largest extinction in the history of the United States.

From 1917 to 1967, dams were built along the length of the Coosa River until it became a series of reservoirs. Dozens of fish, mussels and snails that evolved to live and breed in the fast-flowing water on the shoals and riffles of the Coosa reefs lost their niche. Animals were drowned, cut off from each other or stuck in water so dirty that they could not reproduce, biologists say.

In recent years, scientists have discovered some species hiding in the "headwaters" of the dams, the streams between reservoirs where the Coosa still retains some of its original habitat. So Garner went diving below Lake Logan Martin and found two species that hadn't been spotted since the dams changed the river. Garner knew immediately what the small, brownish spirals were. "One of these I found is pretty distinctive," Garner said. "I've always said it was my favorite snail - I hated it was extinct. It sort of has teardrops around the periphery."

Clark, who began postdoctoral research at the University of Alabama last year, didn't know immediately what she was looking at. But she knew it was unusual. She was accompanying a graduate student to the Cahaba River National Wildlife Refuge in Bibb County when she began wandering around looking in the usual spots a biologist would look for river snails. "Behold, there was this oddball snail under a rock," Clark said. "I didn't know that I'd found an extinct one straightaway, but I knew I'd found something that I hadn't seen before."

The Cahaba pebblesnail, a round, yellow snail only about a quarter of an inch in length, hadn't been spotted since 1965. "That these things are being found is a surprise, but it's not shocking," said Paul Hartfield, an endangered species biologist for the U.S. Fish and Wildlife Service in Jackson, Miss. In the past 15 years, scientists have turned their attention to the snails of Alabama. The study of mollusks had dwindled to nearly nothing by the early 1970s, with students lured away to sexier, high-tech fields, he said. Then after the passage of two federal laws, the Endangered Species Act and the Clean Water Act, the field was in demand again, he said. It took until the 1990s for the science to mature and for great numbers of experts to begin looking for the snails that once covered Alabama's river bottoms.

In recent years, Garner has found several species believed to have been extinct, including a snail in the Locust Fork, a mussel in the Alabama River and a mussel in the Tennessee River. Clark last month collected two snails she believes have never been recorded. "The number of people who are capable of looking grows every day," Hartfield said. "This is a big basin when it was just me out there looking for snails and driving over from Mississippi for four or five days. Now what do we have? We have grad students from Australia."

However, some spots had been surveyed before but only recently have snail hunters had any luck, said Paul Freeman, a freshwater ecologist for the Nature Conservancy of Alabama, the land conservation group that secured the Cahaba refuge for preservation. He believes that may have something to do with cleaner water and better habitat brought by three decades or more of environmental laws. "Folks had been looking for these critters," Freeman said. "It's not just an artifact of people not looking."

Although he believes rapid growth in the river basins has negated many of the improvements, Hartfield said it may not be a coincidence that Alabama Power Co. has managed for good river habitat in the stretch where the two Coosa snails were found. He said their survival will depend on the continued goodwill of the company. He said he only wished more Americans realized the value of mussels and snails, which filter water, clean river bottoms and serve as food for birds, small mammals and aquatic animals. "Those snails and mussels have a lot to do with quality of life for the people of Alabama," he said.

E-mail: kbouma@bhamnews.com 1965.