Bull Trout are members of the char salmon family. It is common for Bull Trout to also be called Dolly Varden, though that is a separate species of fish. Bull Trout are listed as a threatened species under the U.S. Endangered Species Act. One of the reasons for that is that they require specific habitat to thrive including water temperatures that are regularly below 55 degrees. One of its distinguishing features is the white edges on its fins. They have been known to live as long as 12 years and grow up to 25 pounds. When younger, the trout feed on a variety of insects but they soon become predatory, feeding heavily on other fish. Bull Trout spawn in the fall.