The Lake Trout
The lake trout is an important sport fish in the north eastern United States, and is still fished commercially in some parts of Canada. The lake trout is referred to by many names, most notably the mackinaw, lake char, touladi, togue and grey trout. In Lake Superior, it is also known as the siscowet, paperbellies or leans, to refer to the three different kinds found in Lake Superior.
In early American history, the Lake Trout was fished commercially out of the Great Lakes, however, with the construction of artificial canals, the sea lamprey has made its way into the fishing populations, preying on the Lake Trout and reducing its numbers. Additionally, pollution and overharvesting have added their tolls so that from 1930 to 1950, the Lake Trout's population was in danger of becoming extinct.
Today, controlled population increases due to fishery releases, pollution reduction and measures taken to keep lampreys in check have been successful in bringing the lake trout back to the Great Lakes, and while still not commercially viable, they are definitely sought after by sports fishers.
Finding the lake trout:
Lake Trout are a pelagic species, meaning they don't stick to any particular area of the lake, but prefer the open waters. They are generally found between 60 and 200 feet in the deeper lakes, so you'll need a light action rod with six pound test line. You also need three-way swivels and a 2 oz weight for fishing down to 50 feet or a 3 oz weight for fishing down to 80 feet. This is a different philosophy from the traditional heavy weight line with heavy weight - the friction of the thicker line reduces your hook's ability to sink down to the 60foot and deeper depths. The rod required for such fishing is not sensitive enough to alert you to a smallish fish taking the bait.
This is a very good page with information about catching the Lake Trout: http://www.seineriverlodge.on.ca/lake.htm.

