http://www.nytimes.com/2007/10/14/us/14fish.html

After Possible ‘Oops,’ a Trout Rescue Project Regroups Colorado
Division of Wildlife.

via Associated Press

Without DNA tests, the rare greenback cutthroat trout, left, and the
Colorado River cutthroat fish are difficult to tell apart.

By THE ASSOCIATED PRESS
Published: October 14, 2007

DENVER, Oct. 13 (AP) — State and federal biologists, who are smarting
from research showing that they may have been protecting the wrong
fish the past 20 years, are regrouping in their efforts to restore the
rare greenback cutthroat trout to Colorado waters.

Tom Nesler, the state biologist, had hoped to see the fish removed
from the endangered species list during his career. He concedes that
might not happen if it turns out some of the greenback populations
biologists thought they were saving are actually the similar but more
common Colorado River cutthroat trout.

A three-year study led by University of Colorado researchers and
published in August found that out of nine fish populations believed
to be descendants of original greenbacks, five were actually Colorado
River cutthroat trout.

The recovery effort was thought to be near its goal of establishing 20
self-sustaining greenback populations.

“Hey, science happens,” said Mr. Nesler with a shrug as he discussed
the findings.

Not that Mr. Nesler, the chairman of the greenback recovery team,
takes the study lightly. He and other members of the team, which
includes four federal agencies, agencies from three states, an Indian
tribe and a conservation group, are doing further testing and review.

Greenback cutthroat trout were historically found in the drainages of
the Arkansas and South Platte rivers in Colorado, east of the
Continental Divide, and a small part of Wyoming. The Colorado River
cutthroat trout is native to the upper Colorado River basin, west of
the divide.

Greenbacks were declared extinct in 1937 due to overfishing, pollution
from mines and competition from nonnative fish. But researchers said
remnant populations were found in tributaries in the 1950s. The fish
was added to the federal endangered species list in 1978.

Under the state-federal recovery program, biologists used fish they
believed to be descendants of pure greenback cutthroat trout as brood
stock. New fish, raised in hatcheries, were released in different
waters, Mr. Nesler said, not where the remnant populations were.

As team members huddle to chart the course forward, they are also
trying to explain why what they thought were greenbacks were not. In a
letter to the state natural resources chief, four Colorado legislators
denounced “this significant scientific blunder” as a waste of taxpayer
dollars.

The Colorado Division of Wildlife has spent an average of $320,000
annually for the past five years to restore the greenback. Most of the
money has come from state lottery revenue; no state tax dollars have
been used.

In 1998, officials projected a cost of $634,000 to restore the
greenback, with the money coming from a variety of sources. It is not
clear how much has been spent. Figures for the recovery project before
1998 were not available.

Biologists and researchers have suggested that the Colorado River
cutthroat trout once thought to be greenbacks might have been stocked
in various spots in the late 1800s or early 1900s by early settlers.

The team will recommend to the federal Fish and Wildlife Service, the
agency responsible for endangered species, how to proceed.

Meanwhile, it has been thrown another curve.

Tests on a batch of fish not examined during the study produced
results Mr. Nesler said he could not explain: two tests showed they
were Colorado River cutthroat trout, but a third showed they were
greenbacks.

The results could be an anomaly or say something about either the
testing or the fish. They hope to have the answer after more testing.

“As a scientist, I know this kind of stuff happens,” Mr. Nesler said.
“That’s why we didn’t immediately rush to embrace” the research, he
said, “but we didn’t throw it out.”

Mr. Nesler and Bruce Rosenlund of the Fish and Wildlife Service said
the recovery team had taken measured steps all along. The state and
federal agencies helped pay for the university study and have always
worked with outside scientists.

It also was the first time that geneticists told the team that DNA
tests could tell greenback and Colorado River cutthroat trout apart,
Mr. Nesler said. “Up until a year ago, no one could tell us the
difference between the two,” he said.

Andrew Martin, a professor at the University of Colorado and the
study’s principal investigator, said he believed some of the previous
science the team relied on was not the best.

Mr. Martin said that, over all, the Colorado Division of Wildlife and
Fish and Wildlife Service “did a superb job in what they were trying
to do.”

“The problem,” he said, ”was with some of the science and how the
science was evaluated.”

Robert Behnke, a retired Colorado State University professor and a
trout expert, said he had questions about the new research.

“The genetic work might be superb,” Mr. Behnke said, but the study
claims to sweep “doubt and uncertainty under the carpet.”

“Science is not about proof and certainty,” he said, “it’s about
testable hypotheses.”