Colorado Parks and Wildlife will take advantage of the extremely low water levels this fall to restore the fishery at Paonia Reservoir.
When the reservoir starts filling again next spring, the reservoir will be stocked with catchable-size rainbow trout.
The reservoir, which is primarily used for agricultural irrigation, was drained significantly this summer. In late October the reservoir will be lowered further and the water will be treated with Rotenone, an organic chemical that will kill all the fish remaining in the reservoir. The chemical — derived from the root of a tropical plant — is fast acting, works only on aquatic species, leaves no residue and degrades quickly in the environment. Parks and Wildlife agency biologists will then neutralize the chemical through application of an oxidizing agent.
No water will leave the reservoir until it has been determined that it is free of the chemical.
"Rotenone is widely used in Colorado and throughout the nation for fisheries management projects," said John Alves, senior aquatic biologist for the southwest region of Colorado Parks and Wildlife. "It is a safe and effective chemical."
Paonia Reservoir is a poor fishery because of the extreme annual fluctuation of the water level. Northern Pike are present in the reservoir in small numbers and they are small in size. The species holds little appeal to the majority of recreational anglers. Also, pike pose a substantial threat to native fish that live downstream in the Gunnison River.
"The reservoir will be managed for angling recreation, and the majority of Colorado anglers prefer fishing for trout," Alves said.
Paonia State Park is located on the south side of the reservoir and attracts anglers, campers and day-users.
The treatment of the reservoir is planned for the week of Oct. 29.