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Bonytail (Gila elegans)The bonytail has large fins and a streamlined body that typically is very thin in front of the tail. A member of the minnow family, this fish has a gray or olive-colored back, silver sides and a white belly. Bonytail are thought to spawn during late June and early July. They are capable of spawning at 5 to 7 years of age. No reproducing populations are known in the wild. |
Bonytail can grow to 22 inches or more, have been known to live nearly 50 years and are thought to have evolved about 3-5 million years ago. (Also see: Historical perspective.)
Bonytail once were common in portions of the upper and lower Colorado River basins. Now the bonytail is the rarest of the endangered fish species in the Colorado River basin. In fact, upstream of Lake Powell, this fish is nearly extinct. In the last decade only a handful have been captured on the Yampa River in Dinosaur National Monument, on the Green at Desolation and Gray canyons and on the Colorado River at the Colorado/Utah border and in Cataract Canyon. In the lower basin, bonytail exist in Lake Mohave and Lake Havasu.
Recovery strategies:
Bonytail are being raised at the Wahweap Hatchery in Utah and on a smaller scale and in ponds at the Horsethief Canyon State Wildlife Area in western Colorado. Populations are being reintroduced through stocking in the Colorado, Green and Yampa rivers. Managing non-native fish to limit predation on bonytail also will be important.
Recovery goals:
The short-term recovery goal is to prevent extinction in the wild. Once stabilized, a long-term strategy will be developed for the bonytail.
More specific recovery goals are under development and will be published in draft in the Federal Register in early 2001. The recovery goals consist of both demographic criteria and criteria to minimize or remove threats. The objective, measurable criteria are presented for both downlisting and delisting for each of the four endangered fishes throughout their range.