A simulation model was developed to evaluate the performances of two harvest management strategies, constant effort and constant quota, in relation to the magnitude and variability of annual yield for a population of lake whitefish (Coregonus clupeaformis) in northern Lake Michigan. The model consisted of an age-structured, dynamic pool model incorporating a stock-recruitment function subject to environmental variability. Trap-net and gill-net selectivity functions specified the fishing mortality rates operating on each cohort. A constant effort policy produced relatively larger sustainable yields than a constant quota policy. However, the constant quota policy ont-performed the effort policy in terms of reducing the variability in annual yield. The model incorporates the effects of different potential fishing efforts that might be expended in pursuit of the quota. A high risk of population collapse was associated with quota management if a large quota was combined with a high potential fishing effort.
展开▼
