Volunteers Help Reintroduce Native Species in Southwest Colorado

Volunteers and researchers collecting stone flies.
Volunteers and researchers collect stone flies on the Gunnison Gorge to translocate to the Upper Gunnison. Photo by Dana Wilson, BLM.

Stone flies may again be a natural part of the Upper Gunnison if a research project finds their reintroduction has a high chance of success.

Under the project, conducted by Colorado Parks and Wildlife and Western Colorado University, volunteers are collecting stone fly nymphs from the Gunnison Gorge and moving them to BLM- managed lands in the Upper Gunnison. Historically, stone flies were found in the Upper Gunnison, although they are no longer found there naturally.

Volunteers and researchers studying stone flies.
Volunteers are helping researchers study the potential of repopulating the Upper Gunnison River with stone flies. Photo by Dana Wilson, BLM.

Researchers are in their first year of studying whether reintroducing them would be successful. Stone flies are a great food source for trout, so if reintroduction is successful, it could help boost native trout populations and river health.

As part of the project, about 25 volunteers, including students at Western Colorado University, community members and members of Trout Unlimited and local conservation groups, joined biologists to help collect stone fly nymphs on the Gunnison Gorge. Volunteers lifted rocks and substrate in the river where the bugs live, while others held nets to catch them. The group collected more than 4,000 nymphs, which were then transported to the Upper Gunnison and released.

This type of volunteer work is important to the BLM, as it helps the agency partner with others to keep our public lands and habitats beautiful and productive.

Stone flies.
Stone flies are a great food source for trout, and their reintroduction in the Upper Gunnison River would potentially increase native trout health and populations. Photo by Dana Wilson, BLM.