Initiation and Control of Cannibalism in Larval Walleyes

Abstract

Abstract Walleyes (Stizostedion v. vitreum) less than 20 days old attempt to be cannibalistic, irrespective of the presence of alternative food; however, well-fed walleye larvae of this age do not become the prey of other larval walleyes because their escape behavior enables them to avoid capture. On the other hand, walleyes more than 20 days old do not attempt to cannibalize if an alternative food source is available. Escape behavior which makes walleyes difficult to catch by other walleyes develops by 18 days of age. As walleyes become pregressively more difficult to capture by other walleyes, they are attacked less often.