These Bonytail Chub (Gila elegans) were caught out of an irrigation canal via electrofishing, tag and measured then returned to the river safely as part of an ongoing monitoring and recovery program run by the US Fish and Wildlife Service. The bonytail chub is one of many endangered species found in the Colorado River. Once abundant throughout the Colorado River basins, loss of spawning habitat has meant that this species must now be reared in captivity to pervert it from going extinct.