Non-Native Trout Removal for Native Fish Conservation in Grand Canyon National Park

The construction of Glen Canyon Dam in 1966 altered the hydrology of Lower Colorado River, and subsequently non-native fish species were introduced for recreational fishing. To protect the native fish population in Bright Angel Creek, biologists at Grand Canyon National Park initiated a multi-year salmonid removal effort and reintroduced native Humpback Chub to tributaries free of non-native trout. Mechanical removal, combined with fish weirs during spawning and backpack electrofishing surveys, successfully suppressed the non-native trout population by 91% from 2012 to 2018. As a result, native fish now comprise 97% of the fish community. The project was funded by the National Park Service and the Bureau of Reclamation.