Michigan Department of Natural Resources
Institute for Fisheries Research Report No.1759, 1969

Food Habits of Brown Trout in the Anna River, Alger County, Michigan


By Paul R. Hannuksela


      Abstract.-Food habits of brown trout were studied in a small Lake Superior tributary during May-October 1968 to determine possible effects on production of juvenile rainbow trout. The rainbow in this stream is migratory, and thus a steelhead. Brown trout 1.3 to 11.8 inches (33-300 mm) long and 0. I, II and III years of age, fed primarily on Trichoptera. Larger brown trout, 11. 8-20. 6 inches (300-522 mm) long (ages IV and V) ate mostly fish, but very few rainbow trout. Stocked coho salmon were the most frequency ingested fish during May, and slimy sculpins were eaten most frequently during June-October. Brown trout selected salmonids over sculpins to eat, even though sculpins were nine times more abundant than salmonids in the stream.