Fish populations in the Green and Yampa rivers have undergone significant changes in the last century Today, more than 50 fish species can be found in these rivers, but fewer than a third of those are native to the Green and Yampa. Of the 14 native fish species, four are endangered--the razorback sucker, humpback chub, Colorado pikeminnow, and bonytail--and others are declining.
The Green River - After Flaming Gorge Dam
The Green River downstream from the dam became a much clearer, cooler, and calmer river. These changes reduced the number and distribution of several native fish, all of whom were adapted to the rugged conditions of the undammed Green River.
Many of these changes in the river system also created more favorable conditions for non-native fishes.
Non-native fishes, now common in the Green and Yampa rivers, compete for resources including food, space, cover, and physical habitat, and are known to prey on native fishes.
The Yampa River - Unregulated & Vital
Endangered Fish Recovery Program