Park hopes to reduce invasive trout species
The only native trout in Yellowstone National Park are Yellowstone and Westslope Cutthroat, and Arctic Grayling. Over the years those species have been reduced in population due to competition, predation, and hybridization due to other introduced trout.
Lake trout, brown trout, and rainbow trout have become well established throughout the Park and now the Park Service is developing a Native Fish Conservation Plan which they hope will reduce their numbers and increase the numbers of native cutthroat and grayling. Right now the plan is in the scoping phase so you can find out more about it here: Native Fish Conservation Plan/EA Project Home Page
Yellowstone Park’s goal is to boost native fish