Bull Trout, Salvelinus confluentus

The Bull Trout (Salvelinus confluentus) is a char belonging to the family Salmonidae that is native to North America. Historically, this fish has been known as the “Dolly Varden”, but was reclassified as a separate species in the year 1980. This Bull Trout is listed as a threatened species under the U.S. Endangered Species Act.

Like other species of char, the fins of the bull trout have white leading edges. The head and mouth are abnormally large for salmonids, giving it its name. They have been recorded measuring up to 41 inches long and weighing 32 pounds. It may either be migratory, moving throughout large river systems such as lakes or the ocean, or they may be resident, remaining in the same streams for the duration of their entire life. Migratory bull trout are usually much larger than resident bull trout, which rarely exceed 4.4 pounds. They can be distinguished from the Brook Trout (S. fontinalis) by the absence of distinct spots on the dorsal fin, as well as orange, yellow, or salmon-colored spots on the back opposed to red spots with blue haloes on the brook trout. Bull Trout lack the deeply forked tail fin of Lake Trout (S. namaycush, another chur).

This fish can be found in the cold and clear waters of the high mountains and coastal rivers of northwestern North American, including Yukon, British Columbia, Washington, Idaho, Oregon, and western Montana, as well as the Jarbidge River of northern Nevada. A population of these Bull Trout exist east of the Continental Divide in Alberta, where it is the local fish. The historical range of bull trout also included northern California, but they’re likely extirpated.

The young bull trout feed on zooplankton and zoobenthos, particularly chironomids. As they grow, they begin to feed heavily upon other fish.

Image Caption: A Bull Trout from Oregon. Credit: Oregon Department of Fish & Wildlife/Wikipedia (CC BY-SA 2.0)