Lake Trout, Salvelinus namaycush
The Lake Trout (Salvelinus namaycush) is a species of freshwater char that is found mainly in lakes of Canada, Alaska, and the northern United States. They have been introduced into many other parts of the world including Europe, South America and some parts of Asia. In Canada, about 25% of the Lake Trout population is found in Ontario. However, only 1% of Ontario’s lakes contain trout.
The Lake Trout has been known to hybridize with Brook Trout, but such hybrids are almost always reproductively sterile. The hybrids are known as “˜splake’. Splake are commonly produced in hatcheries and then planted into lakes to provide sport fishing opportunities. Common names for Lake Trout include Mackinaw, Lake Char, Touladi, Togue, and Gray Trout. It has also been known as the Siscowet, Paperbelly and Lean in Lake Superior. The Lake Trout is prized both as a game fish and as a food fish.
The Lake Trout is the largest of the char species. The record weighing lake trout was 102 pounds. This fish was fished commercially in the Great Lakes until lampreys, over-harvest, and pollution severely damaged the stockpile. Commercial fisheries still exist in smaller lakes in northern Canada. The Lake Trout depends on cold, oxygen-rich waters to thrive. During the summer months they are pelagic (found deeper offshore) and often found at depths up to 200 feet. It is a slow growing fish and very late to mature.
There are two basic types of lake trout accepted. Some lakes do not have deep water foraging fish during the summer period. In these lakes, the trout become planktivorous (able to detect and feed on zooplankton) and are highly abundant. They grow very slowly and mature at relatively small sizes. In lakes that do contain deep water foraging fish, the trout become piscivorous (feed on prey fish). These trout grow much faster and mature at a much larger size and are less abundant.
Image Credit: NOAA/Wikipedia