Intersite differences in population demography of Mountain Pygmy-possums Burramys parvus Broom (1986–1998): implications for metapopulation conservation and ski resorts in Koskiuszko National Park, Australia Original Research Article

Small, local populations of the endangered Mountain Pygmy-possum Burramys parvus occur on the Koskiuszko Plateau, in south-eastern Australia, including within ski resort lease areas. Between 1986 and 1998 four populations, two within and two outside ski areas, were studied to assess their dynamics and to determine if ski resort management was likely to impact on the conservation of the species. One of the resorts, at Mount Blue Cow, was constructed as the study commenced. Analysis of the 11–12 year data sets showed strong site differences in sex ratios, annual and winter survival rates, site persistence, recruitment and spring weights. Regional trends, attributed to exogenous climatic factors, were evident but population fluctuations were generally uncorrelated and strong site by year interactions occurred for most demographic parameters. Despite this, strong density dependence on all sites in recruitment and to a lesser extent annual survival suggest B. parvus is habitat limited and that social factors drive demographics in these populations. There was no evidence that the ski resort at Mount Blue Cow had any significant impacts above natural yearly variation in demographics in the first 11 years of its operation. However, the highest quality sites, in terms of population size and stability, were those within the two ski resort lease areas. Further, the asynchronous population dynamics, a small amount of migration between habitat patches, differences in site quality and heterogeneity in site structure and aspect, which may contribute to population persistence, indicates that a metapopulation approach to conservation of B. parvus on the Kosciuszko plateau is warranted. This has important implications for long-term conservation of B. parvus in the ski resort areas. These sites will require careful monitoring and management to ensure the continued viability of the resident and surrounding B. parvus populations.