In Arizona, biologists see success in relocation of endangered fish
FLAGSTAFF, Ariz. — A team of biologists that worked in Arizona to relocate an endangered fish from the Little Colorado River has received national recognition as populations of humpback chub appear to be growing.
For more than a decade, biologists from the U.S. Fish and Wildlife Service have moved hundreds of humpback chub each fall about five miles upriver, where there are fewer predators and more food for the fish.
Biologists say they’ve measured increased growth and survival among the translocated chub compared to their downstream counterparts, The Arizona Daily Sun reported.
The chubs’ recovery earned the team of biologists Fish and Wildlife’s 2016 Rachel Carson Award for Exemplary Scientific Accomplishment, which recognizes efforts applied to a conservation problem.
The biologists received help with moving the fish via helicopter from the Arizona Game and Fish Department, the U.S. Geological Survey and the National Park Service.
The world’s largest remaining population of humpback chub is found in Grand Canyon National Park and the Little Colorado River is the population’s main spawning area. The fish could once be found in abundance in the park, but the humpback chub’s numbers have been impacted by the introduction of nonnative predators and the construction of Glen Canyon Dam. The dam pulls cooler waters into the Colorado River and blocks the seasonal floods that used to wash through the canyon.
Biologists started moving humpback chub to a stretch of river above Chute Falls in 2003 and now move about 300 baby fish annually, said Mike Pillow, a biologist with Fish and Wildlife.
The area where the fish are moved has warmer water, abundant food sources and far fewer predators, such as invasive trout and catfish.
The conservation efforts have also been applied by officials at the Grand Canyon, where chub from the Colorado River were transported up Havasu and Shinumo creeks. This helps so “all our eggs aren’t in one basket,” said Randy Van Haverbeke, a senior fish biologist who is involved in the work.
The goal of the project is to eventually be able to remove humpback chub from federal protection, Pillow said.