Bonytail (Gila elegans)

The bonytail is the rarest of the endangered, native fish of the Colorado River and is thought to have evolved around 3-5 million years ago. It has large fins and a streamlined body that is pencil-thin near its tail. Its name describes the fish as an elegant swimmer and member of the “chub” group of minnows. The bonytail has a gray or olive-colored back, silver sides, and a white belly.

Bonytail can grow to 22 inches or more and have been known to live up to 50 years. Bonytail are thought to spawn at 2 to 3 years of age during late June and early July. Bonytail eat insects, plankton, and plant matter.

Status and distribution:

  • Listed as endangered and given full protection under the Endangered Species Act in 1980.
  • Endangered under Colorado law since 1976.
  • Protected under Utah law since 1974.
Bonytail is gently held by a Utah Division of Wildlife Resources biologist. Bonytail silvery on top with a white belly. The fish has a flat mouth with a thin caudlle peduncle by the tail fin. Background shows wood slats and light brown dirt.
A biologist holds a captured roundtail chub photo by by Amy S Martin
A closeup photo of the mouth on a bonytail
USFWS biologist Ben Schleicher displaying an endangered bonytail captured on the Colorado River near Grand Junction Colorado while conducting native fish surveys
A biologist holds a female adult bonytail in a laboratory setting
A biologist holds a male adult bonytail in a laboratory setting
Biologists from UDNR and U.S. Fish and Wildlife Service hold an adult bonytail at Lake Powell Utah
Fish Culturist Zane Olson holds an adult bonytail in front of a fish cultivation pond
A photo of 2 bonytail with a dark background that enhances the fishes bright orange under belly coloration