Bull trout

The bull trout (Salvelinus confluentus) is a char of the family Salmonidae native to northwestern North America. Historically, S. confluentus has been known as the "Dolly Varden" (S. malma), but was reclassified as a separate species in 1980. Bull trout are listed as a threatened species under the U.S. Endangered Species Act (1998) and as vulnerable on the IUCN Red List of Threatened Species.

Description

Like other species of char, the fins of a bull trout have 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 may be either migratory, moving throughout large river systems, lakes, and the ocean, or they may be resident, remaining in the same stream their entire lives. Migratory bull trout are typically much larger than resident bull trout, which rarely exceed 2 kg (4.4 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 halos on the brook trout. Bull trout lack the deeply forked tail fin of lake trout (S. namaycush, another char).