The bonytail fish, also called the bonytail chub or just Gila elegans, is a fish that lives in the Colorado river and other large rivers. Bonytail chubs reach lengths of about 22 inches. It is thought these larger fish are up to 50 years old. Both adults and young bonytail are often confused with other types of chubs. Bonytail chubs eat several aquatic insects, fish worms, algae, plankton and debris from plants. Interestingly, bonytail have adapted to living in swift, fast water areas of the rivers they call home. However, they often stay in backwaters with rocky and muddy bottoms in the day, and open waters in the night. Bonytail chubs repeatedly return to the same areas. Fascinatingly, one study shows that bonytail chubs can survive in water with high levels of total dissolved solids and even seem to seek out these areas. They have the highest tolerance of such waters compared to all species in the bonytail’s genus. This may help them survive habitat destruction and pollutants in water.
The bonytail is extremely endangered and has no known reproducing populations in the wild. From 1976 - 1989, biologists noticed declining populations and 50 bonytail were captured and brought to a hatchery. Their offspring are the only known bonytail chubs in the world. For the bonytail chub’s place in the world to be more stable, many self-sustaining fish populations should be created, and habitats should be legally protected. One reason for the bonytail chub’s sharp decline was the construction of the Hoover Dam; they went extinct in that area by 1950. Another problem facing them were the several sudden habitat modifications during the 20th century.
Photo by Reclamation
Continued habitat degradation will not only affect the bonytail chub but also other animals and plants that live in the area. The bonytail’s adaptation to polluted water may be useful for finding out ways to help other animals survive such areas.
Scientists are working to replace populations with fish bred in captivity, and working to make these populations self sustaining. A potential problem in such small populations is genetic diversity, so scientists must ensure there are enough fish to prevent inbreeding and make sure fish can reproduce in the wild. You can tell people about this amazing fish and donate to organizations that are trying to bring them back from the brink of extinction.
Service, U. (n.d.). Bonytail Chub. Retrieved October 09, 2020, from https://www.fws.gov/nevada/protected_species/fish/species/btail_chub.html
Bonytail (Gila elegans). (n.d.). Retrieved October 09, 2020, from https://www.coloradoriverrecovery.org/general-information/the-fish/bonytail.html
Bonytail. (n.d.). Retrieved October 09, 2020, from https://lcrmscp.gov/fish/bony_chub.html