Brook Trout
(Salvelinus fontinalis)

Length: 10-16 inches [25 - 41 cm]
Weight: 12 - 24 ounces [340 - 680 grams]
Coloring: olive-green to dark brown on back, lighter on sides, and
silvery white on underside. Spawning coloring.
Common Names: Eastern brook trout, speckled trout, coaster, aurora trout, square-tail, sea trout, brookie
Great Lakes Habitat: Lake Superior, Lake Michigan, Lake Ontario, Lake Huron, Lake Erie

Brook trout are the only stream-dwelling trout native to the Great Lakes. In search of clear, cool, and well-oxygenated water, they often move out of streams and into the estuaries and bays of the Great Lakes. Those brook trout that swim into Great Lakes waters are called "coasters." Coasters weigh two to three pounds on average and are usually heavier than their stream-dwelling cousins.

During spawning season (September to December), the male changes color, taking on the deep orange underside. This happens for two reasons: one, it helps camouflage the fish to protect it from predators and two, the intense color serves to attract a spawning partner. This characteristic is similar to that of some birds, where the male's bright colors help attract a mate. Outside of spawning season, the underside color returns to a silvery white.