Humpback Chub of the Little Colorado River is critically endangered. This ancient fish has been in these rivers since before man set foot in the area.
Az Game and Fish Dept is doing something good. They are protecting this ancient AZ. fish from Extinction
The humpback chub Gila cypha, is a rare fish found only in small pockets of fast waters of the Colorado River system in the United States.
The largest remaining population of these unique fish (several thousand adults) lives near the confluence of the Little Colorado River and Colorado Rivers in Grand Canyon. Declines in humpback chub numbers are believed to have been caused by dams on the Colorado River which altered water flow and water temperature, introduced fish species like trout and other game fish which eat small humpback chub to proliferate and lately parasites.
“Each spring researchers set hoop nets in the lower 1,200 meters of the Little Colorado River to catch and mark these unique fish. Captured fish are measured and scanned for the Researcher setting a hoop net in the Little Colorado River presence of a PIT tag and then released. PIT tags are small electronic tags about the size of a rice grain that are implanted within the fish. When a tagged fish is recaptured and scanned, a distinct number is revealed which researchers can use to estimate how many fish are left in the population and how many new fish have been born. Measurements on water flow and water temperature are also recorded as are catch rates of the other fish species that are present. All of this information is used to evaluate trends in humpback chub population size. This research is part of a long-term monitoring project for native fish which began in 1987.”
This study has revealed dramatic declines in the catch of humpback chub in the Little Colorado River. It has also proven to be one of the most effective methods of monitoring humpback chub population size. Continued monitoring will allow researchers to identify management actions, such as planning water releases from Lake Powell that favor humpback chub. Great care is being taken to preserve this unique species for future generations.