July 5, 2009

Salamander faces persistent threat

California tiger salamanders face a threat from a hybrid relative as well as from over development and pollution, researchers said.

Very little development threatened the amphibians 60 years ago when commercial bait sellers in California imported barred tiger salamanders from Texas, a biologist from the University of California Davis told the San Francisco Chronicle. Maureen Ryan of the Center for Population Biology at UC Davis said the larvae of the new salamanders was popular bait, but the adults mated with native amphibians and their offspring flourished -- and now the hybrids imperil frogs and newts as well as the original tiger salamander.

Ryan and colleagues sampled habitats and studied genetics. One of the problems they noticed was that the hybrids have grown much larger than the original salamanders and have strong enough jaws to devour their native cousins.