MOBILE, Alabama -- The snail bobbed at the surface of Three Mile Creek, a fist-sized biological time bomb drifting ever closer to the Mobile-Tensaw Delta and ever closer to making biologists’ nightmares come true.
Dave Armstrong, with the state Division of Wildlife and Freshwater Fisheries, let out a groan when told that an Amazonian snail was found floating about 100 yards downstream from the Conception Street bridge Wednesday afternoon, little more than a mile upstream from the edge of the Delta.
Since the South American snails were discovered in Alabama — first in the pond at Langan Park, then downstream in Three Mile Creek — the state’s prime directive has been to keep the creatures out of the Delta, one of the largest wetland areas in North America.
The snails have a voracious appetite for aquatic plants, and the Wednesday find was proof that the gastropods remain a threat despite an intense multi-year effort to eradicate them.
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http://blog.al.com/live/2011/12/the_snail_that_wont_die.html