Large, voracious char (Salvelinus namaycush) found widely from northern Canada and Alaska to New England and the Great Lakes, usually in deep, cool lakes. They are greenish gray and covered with pale spots. In spring, 5-lb (2.3-kg) lake trout are caught in shallow water; in summer, fish of up to 100 lbs (45 kg) are trolled in deep water. Lake trout were virtually eliminated from the Great Lakes by the sea lamprey, which entered through the Welland Canal in the 1930s. They have been introduced in the western U.S., South America, Europe, and New Zealand.