WSP06866 - Laserfiche WebLink

Home Browse Search

if possible, and compared with historic N,. This metric may be evaluated as a means to determine critical population size for taking fish into captivity into a refuge or for captive propagation. Alternatives for the populations of Humpback Chub in the Upper Colorado River Basin (in priority) 3. Continue to address threats to the species and translocate young-of-the-year (yoy; when available) from nearest populations to river reaches where threats have been reduced or minimized. For example, the Yampa Canyon population might be supplemented with Desolation/Gray yoy once the control of nonnatives is affected in Yampa Canyon. Suggest the movement of no less than 100 yoy per year for at least 5 years. 4. Move yoy to a refuge, i.e., a hatchery such as Ouray or Grand Valley, and expect to add yoyon an annual basis to minimize any genetic changes caused by genetic dri ft or adaptations to hatchery conditions. In addition, funding will be required to provide operation and maintenance of the fish held at the refuge. Identifying refuge, getting permits lined up for signature, and other associated logistics of getting fish out of the wild could be in place in case this is deemed necessary. 5. If a precipitous decline in all populations occurs and is validated', then breeding matrices (e.g.. 25x25 paired matings) should be developed that utilize many individuals from the five diverse populations throughout the Upper Colorado River Basin, with the goal to maintain genetic variation of the original wild populations. 6. Augmentation of the populations should not occur until the threats have been removed or minimized to a level that reintroduced individuals can survive, mature, reproduce, and their progeny do the same. Alternatives for the Grand Canyon Population of Humpback Chub (ill priority) 3. Continue to address threats to the species and translocate yay (when available), that would presumably be lost to the mainstem Colorado River, into tributaries where threats have been reduced or minimized. This strategy of translocation has been preliminarily successful in expanding the population in the Little Colorado River in an upstream direction, past a natural fish barrier, Chute Falls (personal communication. Pam Sponholtz, U.S. Fish and Wildlife Service). Suggest the movement of no less than 100 yoy per year for at least 5 years. Continue to explore other tributaries that may be suitable for translocations. 4. Move yoy to a refuge, i.e., a hatchery such as Willow Beach or Wahweap, and expect to add yoy on an annual basis to minimize any genetic changes caused by genetic drift or adaptations to hatchery conditions. In addition, funding will be required to provide operation and maintenance of fish held at the refuge. Identifying refuge, getting permits DRAFT HBC Genetics Management Plan - 6 n(lhl;?