Oil Slick Threatens Rare Turtles UAB Scientists Have Been Working To Save

Oil Slick Threatens Rare Turtles UAB Scientists Have Been Working To Save
By Stan Diel -- The Birmingham News
April 29, 2010, 9:30AM
http://blog.al.com/spotnews/2010/04/oil_slick_threatens_endangered.html


An oil slick caused by the explosion and sinking of a drilling platform off the Louisiana coast could put at risk a population of rare turtles that UAB scientists have been working to save since 2004.

Biologists have estimated that there are 100 to 150 rare diamondback terrapins living in a marsh at Cedar Point, just north of Dauphin Island. Already at risk of being wiped out by predators, the turtles now face the possibility of an oil slick that could contaminate their food supply, said Thane Wibbels, a professor of biology.

"It could get the entire food pyramid," he said.

Scientists hope that water coming downriver into Mobile Bay will keep the oil slick offshore, protecting the marsh. But they've delayed plans to release captive turtles as part of a repopulation program until they know for sure.

Oil from the rig, which exploded on April 20 and sank, is expected to reach shore as soon as Friday. The greatest concentration of oil is anticipated to come ashore in Mississippi and Louisiana, but Alabama's beaches may be fouled as well.

University of Alabama at Birmingham scientists were studying sea turtles six years ago when they discovered the small population of diamondbacks, which climb onto the beach to lay their eggs each spring. The six- to nine-inch turtles, with webbed feet and strong jaws for cracking snails, hold a unique place in the ecosystem. They're one of the few reptiles that live exclusively in saltwater marshes.

A century ago the turtles were hunted by locals and raised in captivity for sale to restaurants in the Northeast, where they were used to make an expensive stew. The Cedar Point population then was estimated to be at least 10,000, but they lost their cache as a gourmet food, ending commercial breeding, and were devastated by crab fishing traps introduced in the 1930s and 40s.

Today, the estimate of the turtles statewide is fewer than 500, and they're listed in Alabama as a "species of special concern." That listing is one level below "threatened" and two below "endangered."

As much as a third of Alabama's population of diamondbacks today is housed at UAB, where eggs are brought to hatch and babies are raised until they're big enough to survive on their own.

Biologists last year released 10 turtles with the launch of a repopulation effort, and had planned to begin releasing more this week. Instead, they'll wait to see whether oil gets into the marsh, Wibbels said. If the marsh escapes damage, the repopulation effort will resume with the release of about 20 turtles next week.

"What we're hoping for is that the oil will stay offshore," he said. "We'll wait and see."