Nonnative cyprinid removal in the lower Green and Colorado Rivers, Utah

摘要

Controlling nonnative species of fish in the Upper Colorado River Basin has been a concern of the Upper Colorado River Endangered Fish Recovery Program (Program) for many years. Beginning in 1998, the Utah Division of Wildlife Resources (UDWR) was funded to examine the effectiveness and feasibility of removing nonnative cyprinids from the lower Green and Colorado rivers within Utah for the benefit of native endangered fish. The study area included 50 consecutive miles on the Green River and three disjunct 10-mile sections of the Colorado River. Four or five removal trips were made each year in April and May on the Green River and July and August on the Colorado River. On each removal trip, all backwaters in the study area were seined multiple times to remove nonnative fishes.