Lake trout
Lake Trout "(Salvelinus namaycush)" were one of the first non-native species introduced into Yellowstone. They are also the largest fish species in the park growing to an average length of . In 1890 42,000 fingerlings were planted in Lewis Lake and Shoshone Lake at the time, barren of fish because of Lewis Falls. Sometime thereafter, they were also introduced into Heart Lake. Lake trout over have been caught in Lewis, Shoshone and Heart lakes. The park record is from Heart Lake in 1931.