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Summary Alpine and subalpine ecosystems support many endemic species. These ecosystems are increasingly under threat from human‐induced disturbances such as habitat loss and fragmentation as a consequence of ski resort development and expansion. However, limited peer‐reviewed research has investigated the impacts of ski‐related disturbances on wildlife, particularly on reptiles. To address this knowledge gap, we conducted reptile surveys to determine the patterns of reptile distribution and abundance in Australian ski resorts. Then, using a factorial experimental design, we investigated 1) the influence of temperature and predation in driving observed distributions and 2) how a common ski resort management practice – mowing of modified ski slopes – affected thermal regimes and rates of predation of reptiles on ski runs. We found that the removal of vegetation structural complexity through mowing resulted in significantly higher rates of predation on plasticine models, as well as significantly altered thermal regimes. Crucially, mown ski runs had higher maximum ground temperatures that frequently exceeded the recorded critical maximum body temperatures of the target species of lizards. Thus, mowing has the potential to render these areas unsuitable for thermoregulatory purposes for a large proportion of the potential activity period of reptiles. Together, modifications of the thermal environment and elevated rates of predation appear to explain the avoidance of ski runs by reptiles. To facilitate the persistence of reptiles in disturbed subalpine environments, management plans must focus on implementing strategies that reduce the impact of human activities that alter temperature regimes and predation rates on lizards. Synthesis and Applications. We suggest that the retention of structural complexity on ski runs (e.g. through the cessation of mowing during peak reptile activity periods) and/or revegetation with native plant communities will concurrently provide refuge from predators and buffer against extreme temperatures, making ski runs more hospitable to reptiles. Based on our findings, we emphasize that effective management strategies targeting subalpine biodiversity conservation require an understanding of the drivers that determine species distributions in these landscapes.

Evidence of viable populations of Mastacomys fuscus was found in two areas, the Snowy Mountains region in southern New South Wales (including the higher parts of the Australian Capital Territory), and at Barrington Tops in the north. Evidence of M. fuscus was found at 196 of 231 sites at which searches were conducted for faecal remains within the Snowy Mountains region, and at 14 of 27 sites at Barrington Tops. Sites could be classified in six broad habitat types, all having two major components, protection from predators, and grass or sedge to provide food. All sites at which the species was detected were characterised by a mean annual precipitation of >1000mm, a mean annual temperature of <10 O C and altitudes >1000m. The presence of M. fuscus could not be confirmed at sites at lower elevations. Only populations in the Snowy Mountains region, specifically those above the winter snowline (>1500m), may be considered secure in the short term.

Declines have been observed in a number of Australian frog species, many of these at high elevations. Alpine regions in Australia are likely to be particularly subject to increases in ultraviolet‐B radiation ( UV‐B, 280–320 nm) because UV‐B levels increase with elevation and because anthropogenic depletion of ozone has been particularly severe in the southern hemisphere. We compared survivorship of embryos and tadpoles of a declining species of frog, Litoria verreauxii alpina, with those of a sympatric nondeclining species, Crinia signifera, under three ambient UV‐B treatments, unshielded, control, and UV‐B–excluding. Experiments were conducted in artificial water bodies established at three different elevations (1365, 1600, and 1930 m) in the Snowy Mountains of southeastern Australia. The exclusion of UV‐B significantly enhanced survival of L. v. alpina (declining species) at all elevations. Overall, the probability of dying was highest in the unshielded treatments and lowest under the UV‐B–excluding treatment for both species over all elevations. The probability of dying was significantly higher in L. v. alpina than in C. signifera for a given UV‐B treatment at the two highest elevations. Our results support the hypothesis that ultraviolet radiation is likely to be a contributing factor in the disappearance of L. v. alpina at high elevations in southern Australia.

Since the early 1980s, the southern corroboree frog Pseudophryne corroboree and northern corroboree frog P. pengilleyi have been in a state of decline from their sub-alpine and high montane bog environments on the southern tablelands of New South Wales, Australia. To date, there has been no adequate explanation as to what is causing the decline of these species. We investigated the possibility that a pathogen associated with other recent frog declines in Australia, the amphibian chytrid fungus Batrachochytrium dendrobatidis, may have been implicated in the decline of the corroboree frogs. We used histology of toe material and real-time PCR of skin swabs to investigate the presence and infection rates with B. dendrobatidis in historic and extant populations of both corroboree frog species. Using histology, we did not detect any B. dendrobatidis infections in corroboree frog populations prior to their decline. However, using the same technique, high rates of infection were observed in populations of both species after the onset of substantial population declines. The real-time PCR screening of skin swabs identified high overall infection rates in extant populations of P. corroboree (between 44 and 59%), while significantly lower rates of infection were observed in low-altitude P. pengilleyi populations (14%). These results suggest that the initial and continued decline of the corroboree frogs may well be attributed to the emergence of B. dendrobatidis in populations of these species. KEY WORDS: Amphibian declines · Corroboree frog · Amphibian chytrid fungus Resale or republication not permitted without written consent of the publisherContribution to DAO Special 4 'Chytridiomycosis: an emerging disease'