The bull trout (Salvelinus confluentus) is a char of the family Salmonidae native to northwestern North America. The bull trout is listed as a threatened species under the U.S. Endangered Species Act. Like other species of char, the fins of a bull trout has white leading edges. Its head and mouth are unusually large for salmonids, giving it its name. Bull trout have been recorded measuring up to 103 cm (41 in) in length and weighing 14.5 kg (32 lb). Bull trout can be differentiated from brook trout (S. fontinalis) by the absence of distinct spots on the dorsal fin, as well as yellow, orange, or salmon-colored spots on the back as opposed to red spots with blue haloes on the brook trout. Bull trout arefound in the cold, clear waters of the high mountains and coastal rivers of northwestern North America, including Yukon, British Columbia, Washington, Oregon, Idaho, and western Montana, as well as the Jarbidge River of northern Nevada.