The Trout of the Great Lakes.

—The fish known as trout in the Great Lakes belong to a different genus from those already mentioned, namely, genus Cristivomer. It has, however, the typical spots, which are of a grayish color instead of red or black like those of the other trout which have been mentioned.

The principal species which abounds in the Great Lakes is the Mackinaw trout (Cristivomer namaycush). It is also found in the large lakes from Maine westward to the Pacific ocean and even to northern Alaska. This is the largest species of trout. The average weight of the fish probably does not exceed 15 or 20 pounds. Individual examples have been found weighing over 100 pounds. There is only one common fish which exceeds it in weight, namely, the sturgeon. Next to the white fish it is the most important commercial fish of the Great Lakes. The supply of lake trout has been diminishing and the price increasing for several years. The spawning season of lake trout begins in September and continues until December.

Composition of Lake Trout.—
Fresh.Dry.
Water,69.14percent
Protein,18.22„60.10percent
Fat,11.38„36.80„
Ash,1.26„4.90„
Composition of Brook Trout.—
Fresh.Dry.
Water,77.72percent
Protein,18.97„86.62percent
Fat,2.10„9.16„
Ash,1.21„5.39„

The above data show that lake trout has a flesh which approximates in composition that of Pacific salmon, being quite rich in fat, while the brook trout has a composition more like the Atlantic salmon, being very rich in protein and poor in fat. Trout of all kinds are used practically in only a fresh state. The catch is not large enough to warrant the establishment of canning factories and all that are caught in the northern and central northern lakes and streams find a ready market in a fresh state at much more remunerative prices than could be obtained by canning. It is always a fortunate circumstance when the condition of the catch and of the market are such as to enable the fish to be eaten as fresh as possible from the water. Fish is a kind of food which is never improved by keeping in any way and is at its best the minute the fish is taken from the stream. The brook trout do not belong to the same genus as the lake trout but to the genus Salvelinus. They have a general resemblance, however, to that genus. As a fish to be caught by the hook and as a victim of sport the brook trout perhaps occupies the highest place among the fish of the country; especially is it sought for in the mountain streams, and it occurs in most parts of the northeastern United States. It extends from Maine to northern Georgia and Alabama, especially in the Appalachian Mountains and west through the Great Lakes to the Mississippi, while in Canada it is found from Labrador to the Saskatchewan.

The brook trout has been especially cultivated by the U. S. Bureau of Fisheries and introduced into waters in the United States where it is not found naturally. The season for spawning for the brook trout is in the autumn, when the water is growing colder, and continues from August to December, according to the latitude. In spawning time the fish come up into the smallest parts of the stream where shallow water can be found. The eggs remain until the next spring, when they are hatched. The brook trout varies greatly in size, according to the magnitude of the stream. In the small streams it weighs often less than 1⁄4 pound, while in large streams it weighs 2 or 3 pounds. The large trout has almost disappeared from the small streams as a result of the activity of fishermen.

There are many other species of trout which are known in different parts of the country. For instance, the Dublin Pond trout of Dublin Pond, N. H., the Dolly Varden trout in the northern Pacific states and Alaska, the Sunapee trout in the northeastern states, and the Blueback trout in Maine. These fishes all have practically the same quality, varying only in minute details, and have the same value as a food.