The body of the Brook Trout is elongated with an average length of 15 to 20 inches and an average weight of 2.2 to 13.2 lbs. The body has its greatest depth at, or in front of, the origin of the dorsal fin. It also has an adipose fin and a caudal fin that are slightly forked. Coloration is very distinct and can be spectacular. The back of the brook trout is dark, olive-green to almost black. Sides are lighter becoming silvery white ventrally. On the back and top of the head are wormy cream colored wavy lines which break up into spots on the side. The fins are also distinct. The dorsal and caudal fins have black lines and the anal, pelvic and pectoral fins have white edges followed by black then reddish coloration.