Like many waters in the United States, stocking of non-native fish species was common in the late 1800's. And continues in many regions still. However, these non-native species, stocked for sport and food, can alter aquatic landscapes drastically and potentially extirpate native species altogether. In 1936, the National Park Service gave its first formal guidance to discourage non-native stocking and encourage stocking of native fish in Rocky Mountain National Park. Stocking stopped but not before 20 million fish had been stocked in the park's waters between 1886 and 1968. At this time, nearly all of the waters were inhabited by non-natives.

Native Cutthroat Trout, Photo Credit: NPS

Fish known to native to the area now known as Rocky Mountain National Park are cutthroat trout, suckers and sculpins. Historically, these fish were only found in the lower reaches as waterfalls and cascades served as migration barriers. Due to the cold water temperatures, it is thought that many of the park's waters were originally fishless.

With the assistance of 17 native trout reclamation projects, Rocky's native fish have continued to be restored and many non-natives have been removed. The Colorado River cutthroat trout and the Greenback cutthroat trout are two species of cutthroat native to RMNP waters.

Colorado River Cutthroat Trout Greenback Cutthroat Trout

Photo Credit: NPS     

A working list of the fish species in RMNP can be found at IRMA Portal NPSpecies.

Information about fishing opportunities in Rocky can be found on the park's Fishing page.

Happy Fishing

Illustration by Zoe Mozert