The Paiute cutthroat trout, listed as a threatened species, is in trouble because it has become hybridized with other trout in the Silver King Creek in California.
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WALKER, Calif. — The U.S. Fish and Wildlife Service and the California Department of Fish and Game are moving forward with a plan to restore one of the country's rarest trout to its native habitat by poisoning a remote Sierra stream, despite ongoing criticism. An environmental impact report — ordered by a federal judge in 2005 — is in the comment period and expected to be finalized by October. The project, at Silver King Creek, a wilderness area south of Lake Tahoe, is scheduled for next summer.
Since 2002, protests and legal action have delayed the project to restore the rare Paiute cutthroat trout. "They want to put an agent in the water that kills everything," says Patty Clary of Californians for Alternatives to Toxics, an opponent of the project. "That's not OK. This is a very precious area." Another lawsuit could be filed if the final impact report fails to adequately address concerns over the proposed fish poisoning, Clary says.
"It's still a very exciting project, and it's very viable," counters Bob Williams, field supervisor for the U.S. Fish and Wildlife Service in Reno. The Paiute cutthroat trout, listed as endangered in 1967 and upgraded to threatened status in 1975, has become hybridized with other trout in the stream, he says.
The plan calls for the poison rotenone to be used along 11 miles of Silver King Creek, its tributaries and Tamarack Lake Creek. Williams says hybridized trout could then be removed and the stream restocked with pure Paiute cutthroats from hatcheries.
Williams says rotenone would have no long-lasting impact on aquatic life and that macro invertebrates would recolonize the treated area within a few years. California biologists have twice before used rotenone to rid Lake Davis, a Northern California trout fishing lake, of invading northern pike that they feared would escape into the Sacramento-San Joaquin river delta.
The first attempt in 1997 failed, and pike returned two years later.
More:
http://www.usatoday.com/news/nation/environment/2009-07-08-raretrout_N.htm