Whoops! Trout restoration used wrong fish

Biologists call findings a setback but say there is still hope

These photos provided by the Colorado Division of Wildlife, show the endangered greenback cutthroat trout, left, and the Colorado River cutthroat trout.

updated 8:34 a.m. ET Sept. 6, 2007

DENVER - A 20-year government effort to restore the population of an endangered native trout in Colorado has made little progress because biologists have been stocking some of the waterways with the wrong fish, a new study says.

Biologists called the finding a setback and a potential black eye but said there is still hope for restoring the greenback cutthroat trout because at least four pure populations of the fish have been identified.

The three-year study was led by University of Colorado researchers and published online in Molecular Ecology on Aug. 28.

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The U.S. Fish and Wildlife Service, which is heading the recovery effort, said it is reviewing the findings.

The study said that out of nine populations of fish believed to be endangered greenback cutthroat trout that were descendants of survivors, five were actually the Colorado River cutthroat trout, which look similar but are a separate and more common subspecies.

The other four populations were greenbacks.

The recovery effort by Colorado and federal biologists was thought to be close to its goal of 20 self-sustaining populations of at least 500 fish each.

Bruce Rosenlund of the U.S. Fish and Wildlife Service in Denver said federal and state agencies working on restoration believed the fish were found in 142 miles of waterways, including in Rocky Mountain National Park.

Researchers, though, said that based on genetic test results, the greenback cutthroat trout's range is only 11 miles of streams.

The study said the results imply that the effort has "failed to improve the species' status."

Rosenlund said other scientists will read and comment on the research. He said biologists working on restoring the greenback trout want to see "the science played out."

"The report is just a continuation of different expert input provided to the team for consideration for restoration," said Rosenlund, the project leader for the agency's assistance office.

State and federal biologists will continue with other key parts of the recovery program, such as habitat restoration.

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CONTINUED: Long term success?

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