General Description

Lake trout have a body shape similar to that of trout and salmon. They generally have small cream or yellow, irregular shaped spots on a silvery-to-dark background. Males and females are similar, with males having a slightly longer, more pointed snout. Lake trout can be distinguished from other chars by the absence of pink spots and their deeply forked tail. A breeding male has dark stripes on its side, and lacks the red or orange exhibited by Dolly Varden and Arctic char. There is usually a white leading edge on the pectoral, pelvic, and anal fin. Alaska lake trout can live longer than 50 years but more typical maximum ages are around 20 years. The maximum size attained in some Alaskan populations probably exceeds 50 pounds, and 8- to 10-pound fish can be taken in many of the state’s fisheries. The current record is a 47-pound laker caught in Clarence Lake in July 1970.

Life History

Lake trout prefer large, deep, cold lakes in which they spend their entire lives. Spawning takes place over clean, rocky lake bottoms in September or October. Lake trout do not excavate a redd but instead broadcast spawn over the spawning bed. Males reach the spawning sites before the females each year and each evening. Spawning takes place at night with peak activity occurring after dusk. Eggs hatch early in the following spring. Little is known about the early life history of lake trout which are thought to be reclusive while feeding on plankton during their first few years of life. Spawning occurs for the first time after five to eight years. Lake trout spawn every other year or less frequently in northern Alaska, while in more southern Alaskan populations, such as those on the Kenai Peninsula, spawning may occur annually. Lake trout growth varies from place to place depending on diet, water temperature, altitude, and genetics.

Feeding Ecology

The diet of lake trout varies with the age and size of the fish, locality, and the food available. Food items commonly include zooplankton, insect larvae, small crustaceans, clams, snails, leeches, several kinds of fish, mice, shrews, and even occasional young birds. When available, lake trout may feed extensively on other fish such as whitefish, grayling, sticklebacks, and sculpins