Fish previously thought to be extinct found naturally reproducing in Colorado

Colorado Parks and Wildlife (CPW) has announced that the greenback cutthroat trout is naturally reproducing in the state after more than 10 years of rescue efforts to stop it from going extinct.

The fish was considered extinct in 1937 and it was thought for decades that only the Colorado River and Rio Grande cutthroats had survived while the greenback and yellowfin had died out due to mining, overfishing, as well as competition from other kinds of trout.

CPW found wild greenback cutthroat trout in Bear Creek, in the southwestern parts of Colorado Springs, as well as in the drainage from the Arkansas River, in 2012. The fish are thought to have been taken to Bear Creek from the South Platte Basin in the late 1800s during a tourist fishing trip, the office of Colorado Governor Jared Polis said in a press release.

CPW and other agencies worked to protect the waters following the 2012 discovery. More than a decade later, the trout has now also been found to be naturally reproducing in Herman Gulch.

“While we will continue to stock greenback trout from our hatcheries, the fact that they are now successfully reproducing in the wild is exciting for the future of this species,” Mr Polis said in a statement. “This is a huge wildlife conservation success story and a testament to the world-class wildlife agency Coloradans have in Colorado Parks and Wildlife. Colorado’s ecological diversity strengthens our community, supports our anglers, and our thriving outdoor recreation economy.”

“CPW’s staff and our partner agencies have worked for more than a decade to restore this beloved state fish, and today’s news truly highlights the success of the work,” he added.

The acting director of CPW Heather Dugan said in a statement that “the bedrock mission of Colorado Parks and Wildlife is to perpetuate the wildlife resources of the state”.

The greenback cutthroat trout was once thought to be extinct (Colorado Parks and Wildlife)
The greenback cutthroat trout was once thought to be extinct (Colorado Parks and Wildlife)

“This is a tremendous example of CPW fulfilling its mission. I am so proud of all the aquatic researchers, biologists, hatchery staff, volunteers and partner agencies who helped achieve this milestone of naturally reproducing greenback cutthroat trout,” she added. “Despite more than a decade of setbacks and frustrations, CPW staff worked as a team across departments and across regions, stayed focused on the goal and now we gave this great news. It’s a great day.”

“It’s just great to see all the hard work everyone has put in to save these fish is starting to pay dividends,” Kevin Rogers, an aquatics researcher with CPW said. “This is just another affirmation that our conservation practices work and that we can save species on the brink.”

The assistant aquatic section manager at the agency said that “the news of the natural reproduction of greenback cutthroat trout in Herman Gulch is truly monumental”.

“CPW aquatic biologists in the Southeast Region have worked incredibly hard to protect and preserve the only known population of greenbacks in Bear Creek,” he added. “Our hatchery staff along with our federal hatchery partners overcame immense obstacles to be able to replicate the species in captivity. Now to see them on the landscape in their native habitat replicating on their own is a huge sense of accomplishment for everyone involved.”

Fort Collins aquatic biologist Boyd Wright said “our team of field technicians literally high-fived right there in the stream when we captured that first fry that was spawned this year”.

“When moments later we captured a one-year-old fish produced in 2021, we were truly beside ourselves,” he added. “After many years of hard work and dedication, it is extremely satisfying to see our efforts paying off.”

The native aquatic species coordinator at CPW, Harry Crockett, noted that “we found a greenback that was born in Herman Gulch that was already a year old”.

“This indicates successful reproduction both this year and last, plus overwinter survival. This is important because trout that survive to one year are likely to live even longer,” he added.