This summer, we brought you the saga of Colorado's state fish, the greenback cutthroat trout. Biologists worked to bring back the species, which was once thought extinct, only to discover they'd saved the wrong fish. But the biologists didn't give up and efforts are now underway to grow the state's last-known (and very small) greenback population. In addition, the feds are in the process of deciding whether to list the greenbacks as endangered.
Meanwhile, that decision has been made for another subspecies of trout, the Rio Grande cutthroat trout, which live in southern Colorado and New Mexico -- and which happen to be New Mexico's state fish. After evaluating current scientific information, the U.S. Fish and Wildlife Service has decided that the Rio Grande cutthroats are not endangered.
There are currently 122 populations of Rio Grande cutthroat trout, according to Fish and Wildlife spokeswoman Lesli Gray. The populations consist of a few hundred to several thousand fish each, but the feds don't know exactly how many individual fish remain.
By comparison, there is only one truly wild population of greenback cutthroat trout remaining, and it exists in a narrow, four-mile stretch of Bear Creek outside of Colorado Springs. Biologists estimate it consists of 500 to 700 individual fish. In August, biologists released an additional 1,200 one-year-old greenbacks into Zimmerman Lake west of Fort Collins. Those fish were spawned in hatcheries using the, uh, genetic material of fish from Bear Creek with the intent of releasing them to establish another wild population.
A greenback cutthroat trout from Bear Creek.
Courtesy of Doug Krieger
The U.S. Fish and Wildlife Service was first asked to consider the Rio Grande cutthroat trout for the endangered and threatened species list in 2008. At the time, the fish was facing threats that included "population fragmentation and isolation, small population size, non-native trout, drought, and fire." Non-native trout can replace or breed with native trout such as the Rio Grande, wiping them out entirely or creating hybrid species.
But things seem to have improved over the intervening years. "Since 2008, aggressive conservation efforts by the New Mexico Department of Game and Fish and its partners have enhanced or restored pure-strain native cutthroats," says a statement from the New Mexico department. "Rio Grande cutthroats now occupy about 700 miles of stream habitat.
"After reviewing current scientific information about the cutthroat's populations, genetic diversity and habitat conditions in its historic range in northern New Mexico and southern Colorado, the federal agency deemed that the fish is in no danger of extinction," the statement continues. "The Rio Grande cutthroat was designated a candidate for listing in 2008, mostly because its habitat had dwindled to 11 percent of what it once was."
But just because the Rio Grande won't be included on the endangered and threatened species list at this time doesn't mean it couldn't be considered again in the future. The feds are "requesting that any new information concerning the status of or threats to the Rio Grande cutthroat trout be submitted to the New Mexico Ecological Services Field Office whenever it becomes available. New information will help the (Fish and Wildlife) Service monitor the Rio Grande cutthroat trout and encourage its conservation."
In the meantime, watch the video below, courtesy of Colorado Outdoors magazine, to see these beautiful fish in their natural habitat in southwest Colorado.