HARVEST YIELDS FROM MOOSE POPULATIONS SUBJECT TO WOLF AND BEAR PREDATION

• Main Authors: Van Ballenberghe, V., Dart, Joe
• Format: Article in Journal/Newspaper
• Language: English
• Published: Lakehead University 1982
• Subjects: Canis lupus
• Online Access: http://alcesjournal.org/index.php/alces/article/view/1545

A single conceptual model is presented that links several important variables based on the ratio of moose per predator at equilibrium. This ratio is determined by annual predator kill rates, the potential rate of increase of moose, and mortality of moose due to hunting. This conceptual model guided our thinking in the construction of a simulation model designed to illustrate how predation by wolves (Canis lupus) and bears (Ursus spp.) affected harvest yields for humans. A model moose population that displayed sigmoid population growth resulting from density dependent mortality and fecundity formed the heart of the model. Demographic parameters were typical of certain Alaskan moose populations. Maximum sustained yield for bull plus cow harvests fell to 40% of predator free conditions when predation by wolves or bears was intense. Under these conditions, bull only hunts provided an equivalent numerical yield to either sex hunts but had a much higher margin of safety for management errors. Prediction intensities that reduced sustained yields for humans to zero were determined; management implications are discussed.