When John C. Frémont and Kit Carson ascended the Truckee River on January 16, 1844 they called it the Salmon Trout River, after the huge Lahontan cutthroat trout (Oncorhynchus clarki henshawi) that ran up the river from Pyramid Lake to spawn. However, the river was ultimately named after a Paiute chief known as Truckee who in 1844 guided an emigrant party from the headwaters of the Humboldt River to California via the Truckee River, Donner Lake, and Donner Pass. Appreciative of their Native American's guide's services the party named the river after him. The chief's real name might not have been Truckee, but perhaps Tru-ki-zo, which could have become distorted as Truckee. There are numerous other theories about Chief Truckee and his name.