"Rare Trout Survives in Just One Stream, DNA Reveals"

"The rare greenback cutthroat trout, Colorado’s state fish, is even more imperiled than scientists thought, a new study suggests. By analyzing DNA sampled from cutthroat trout specimens pickled in ethanol for 150 years, comparing it with the genes of today’s cutthroat populations, and cross-referencing more than 40,000 historic stocking records, researchers in Colorado and Australia have revealed that the fish survives not in five wild populations, but just one."



"Stocking records and the tangled genetic patchwork of trout in the southern Rocky Mountain region suggest that efforts to replenish populations were far more extensive and began earlier than previously recognized. Between 1885 and 1953, state and federal agencies stocked more than 750 million brook trout, rainbow trout and cutthroat trout from hatcheries into streams and lakes in Colorado, the researchers found.

The study, published on Monday in the peer-reviewed journal Molecular Ecology as a follow-up to a 2007 study led by the same biologist, Jessica Metcalf, yielded some findings that “may be uncomfortable,” Kevin Rogers, a researcher for Colorado’s state parks authority, said in a call with reporters."

Josie Garthwaite reports for the New York Times' Green blog September 25, 2012.
 

Source: Green/NYT, 09/26/2012