Trout and Perch Populations at Loch Leven, Kinross

Abstract

The annual production of trout in Loch Leven lies between 2·2 and 3·9 g(wet).m−2, and of perch between 5·1 and 67·4 g(wet).m−2. Between June and September adult trout consumed 3·7 times their own wet body weight of food, and adult perch 6·58 times, the daily intake decreasing from the beginning to the end of the period. The principal dietary components of the two species were the same, Asellus and perch fry being quantitatively the most important. Comparisons are made between field estimates of food consumption, laboratory estimates of food requirement, and field estimates of food production.