Variation in growth and reproduction of walleye (Stizostedion vitreum) in three Manitoba lakes

Abstract

Growth, lifetime egg production and biomass, and lipid accumulation in three female populations of walleye (Stizostedion vitreum) were studied. Two populations inhabit large, heavily exploited Canadian prairie lakes and the third inhabits a smaller, cooler, unexploited boreal lake in the Canadian Shield. Fish in the unexploited population grew more slowly and to a smaller asymptotic size than those in the other two populations. Although annual reproductive output per individual was less for this population, the reproductive life-span was greater. Lifetime egg production and ovary lipid biomass per recruit appeared to be similar (within 13%) for female walleye in the three different populations. The significance of energy allocation in the life history of these populations is discussed.