Lake trout (Salvelinus)
These torpedo-shaped fish have light colored spots on a dark gray background. There is a hint of orangish red on the fins. This background varies from silver to almost black depending on where the fish is from. In the Great Lakes region, the background is almost completely silver. This can make it hard to see the pale colored spots. Lake trout have a large head with teeth on the jaws, tongue and roof of the mouth.
Although the brook trout and lake trout are sometimes confused, one can distinguish between the two species by examining the tail. Lake trout have a very pronounced forked tail while the brook trouts is flat. Of course, the biggest difference between the species is size. Brook trout rarely exceed 2 pounds, while lake trout commonly grow larger than 15 pounds and as heavy as 50. The world record lake trout is 72 pounds.
Lake trout are opportunistic and carnivorous, or meat eating. Younger fish eat a variety of invertebrates, but once they reach adulthood, they feed mostly on prey species such as chubs, sculpin, smelt and alewives. Some lakers, especially those confined to extremely deep water, will continue to feed on large invertebrates through adulthood.
Lake trout are very fast swimmers, therefore, they don't need to ambush their prey like largemouth bass and northern pike. They will simply follow large schools of prey fish and attack weak or wounded minnows that stray from the school.
Lake trout are native to the Great Lakes as well as Alaska, Illinois, Indiana, Maine, Massachusetts, Michigan, Montana, New Hampshire, New York, Vermont, and Wisconsin. Other states have since introduced the lake trout: Colorado, Idaho, Kentucky, Maryland, Minnesota, Nevada, New Jersey, New Mexico, North Dakota, Oregon, Tennessee, Utah, Washington, West Virginia, Wyoming. Lake trout are also native to most of the Canadian provinces.
The lake trout is the only member of the salmonid family (trout, salmon, char) that spends its entire life cycle in lakes. In their southern range, they will inhabit some of the deepest water in a lake. In the colder northern range, they are found in both shallow and deep lakes, as well as streams or rivers that feed into a lake.
The lake trouts preferred temperature range is 50 to 60 F. When lake surface temperatures begin to rise, they will often move to extremely deep water to find their comfort range. Depths of 50 to 300 feet are common. Lake trout will cruise open water but, like many game fish, they will hold near some sort of structure in the lake, especially steep drop-offs, ridges, and deep sunken islands and humps. The availability of food is also a big factor in lake trout location.
- The genus name of the lake trout, Salvelinus, is an old name for char. The species name, namaycush, is a Native American name meaning “tyrant of the lake.”
- Lake trout in the Great Lakes were on the decline from the 1930s to the 1950s due to heavy fishing pressure and the presence of the sea lamprey parasite. Lake trout were nearly extinct in Lake Michigan but were later reintroduced and are now back to healthy population levels.
- Unlike most trout, lake trout spend the majority of their lives in solitary conditions except when spawning.
- Introduced lake trout have become a problem in some lakes. In California, for instance, they are partially to blame for the decline of the Lahontan cutthroat trout from Lake Tahoe. Lake trout can also displace bull trout out of lakes in some low level lakes by competing for food and space.