APPLICATION OF POPULATION VIABILITY THEORY TO MOOSE IN MAINLAND NOVA SCOTIA

Abstract

Populations of moose (Alces alces americana) in mainland Nova Scotia, Canada, have been reduced to approximately 1,000 individuals fragmented into a number of isolated populations. Although the data required for a comprehensive population viability assessment (PVA) are not currently available, there are some general rules concerning minimum viable population (MVP) size that may be applied for a preliminary assessment. Genetic evidence suggests that, in general, a genetically effective population (N_e) of 50 individuals is required for short-term persistence and 500 to 5,000 individuals are required for long-term survival. Census population size (N) is generally larger than N_e, and a 10:1 relationship between N and N_e has been roughly established in moose populations elsewhere. Given this relationship, N = 5,000 individuals may be required for long-term viability. Based on current home range size (30-55 km²) and population density (0.05/km²), the minimum critical area required by a population of this size is estimated to be approximately 100,000-200,000 km². Strategies for moose conservation and forest management should concentrate on (1) conducting genetic, population, and habitat analyses to increase understanding of population viability and limiting factors; (2) reestablishing connectedness among discrete populations to form a viable metapopulation; (3) protecting/enhancing habitat to meet the critical requirements of a viable population; and (4) increasing carrying capacity of available habitat to support a greater population density.