Bull Trout

The Bull Trout belongs to a branch of the trout family called "chars," along with the Lake Trout, (Eastern) Brook Trout, and Dolly Varden (which was once considered to be the same species as the Bull Trout). Early naturalists had this to say about the fish: Bull Trout are by far the most active and handsome of the trout, they live in the coldest, cleanest and most secluded waters. No higher praise can be given to a Salmonid than to say, it is a char. (Jordan and Evermann 1896)At one time, bull trout were common to all the major river systems flowing from the eastern slopes of the Rocky Mountains as far as Alberta's prairie and parkland. When anglers began stocking streams with new species in the early 1900s, many saw bull trout as unwanted predators that fed on the more favored species. They removed large bull trout to improve the survival of other fish. During the last 25 years, bull trout numbers have declined even more, primarily as a result of over fishing. This species is not in immediate danger of extinction in Alberta but could easily disappear from some lakes and streams. Bull trout can weigh up to 10 kg and measure 30-70 cm in length. The name was inspired by the large head and jaws in comparison to its body. The key to identifying this species is the absence of black spots on the dorsal fin. Bull trout mature slowly, often spawning for the first time in their fifth or sixth year. Some females do not spawn every year. Water temperatures below 9 C 48 degrees Fahrenheit trigger spawning between mid-August and mid- October. Trout seek out small, spring-fed streams that provide a continuous supply of oxygen for developing eggs. The female digs a nest or "redd" among the gravel where she deposits up to 5,000 eggs. Male fish swim nearby and release milky-white sperm or "milt" to fertilize the eggs. With the help of the current, the female then covers the eggs with gravel. The adults then move downstream for the winter. For the next six or seven months, the eggs incubate in their gravel nests. They begin to hatch during March and April. Although adults can withstand water temperatures up to 64º F, eggs do best with temperatures of no more than 36º F. In fact, temperatures above 46º F can reduce bull trout egg survival by at least 75 percent. Because of diverse adaptation techniques, the life cycle of bull trout is quite varied. They are known to exhibit four distinct life history forms. Lifespan: Up to 20 years. Bull Trout that live in streams rarely grow to more than 4 pounds, but lake inhabitants can weight above 20 pounds, with the U.S. record Bull Trout weighing in at 33 pounds. .

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