Lake trout
Non-native Lake trout were discovered in Yellowstone Lake in 1994, and were believed to have been either accidentally or intentionally introduced as early as 1989 with fish taken from Lewis Lake. The introduction of Lake trout has caused a serious decline in the Cutthroat trout population and the National Park Service has an aggressive Lake trout eradication program on the lake. All Lake trout caught by anglers must be killed. If the Cutthroat Trout isn’t protected from this invasive fish then ecologist predict that they could see a decline in surrounding birds and mammals that are natural predators to the Cutthroat Trout. The Longnose sucker is an invasive fish that was believed to be introduced into the Yellowstone Lake in the late 1980s or early 1990s. With this foreign species in the Lake researchers have noticed a shift in the food chain. They have seen a rapid decline in the population of the Cutthroat Trout which in turn could cause other animal’s populations to start declining. From studies done they have found that the Longnose sucker is predator to the Cutthroat Trout.