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.

No abstract

Alpine-subalpine areas are sensitive environments that support large numbers of endemic species. They are also popular for human recreation. Increasing demands for tourism means that infrastructure in alpine resorts is expanding. Consequently, habitat is being modified and fragmented, potentially adversely affecting fauna. However, research investigating the effects of ski resorts on wildlife, particularly reptiles, is limited, and the effectiveness of management strategies in mitigating adverse impacts is unknown. To quantify the effects of ski-related disturbances on specialist and generalist reptile species, we surveyed sites in disturbed and undisturbed subalpine habitats. We also examined vegetation composition and habitat structure to determine whether structural or compositional habitat features were driving patterns of reptile occurrence. Our results indicate that the effects of ski-related disturbance varied between species, but that adverse effects -particularly on ski runs -were more pronounced for specialists. Given that each species studied was positively associated with compositional or structural features of the environment, we argue that alterations to these habitat attributes when creating ski runs will suppress lizard abundances in these areas. However, while ski runs have an adverse effect on reptiles, the persistence of these animals in ski resorts can be facilitated by retaining habitat structure and minimizing disturbance to native vegetation.

Summary Feral Horse (Equus caballus) impacts in northern Kosciuszko National Park, New South Wales, Australia are directly occurring in habitat of the nationally threatened Broad‐toothed Rat (Mastacomys fuscus). This species is endemic primarily to the mountain regions of south‐eastern mainland Australia and Tasmania, with a disjunct population at Barrington Tops. The Broad‐toothed Rat's preferred habitat is being increasingly impacted by browsing and trampling associated with the expansion of feral horse populations. This study surveyed 180 sites supporting preferred habitat for this species to determine Broad‐toothed Rat presence and relative abundance in relation to the level of feral horse impacts within the reserve. There was a significant negative relationship between feral horse impacts and both Broad‐toothed Rat presence and abundance. No scats were identified at localities where feral horse impacts were severe, and at moderate horse impact sites, there was a proportion (34%) without scats found. Locations with low horse impacts had little impact on Broad‐toothed Rat occurrence. As feral horse populations increase, Broad‐toothed Rat populations may be further impacted. Such impacts will be due to the loss of vegetation cover from feral horse trampling and grazing, making animals more vulnerable to predation by predators or impacting on their ability to disperse to more suitable habitat. Habitat remnants and vegetation corridors along drainage lines require protection from feral horses to prevent localized extinctions of Broad‐toothed Rat.

Aim We evaluated whether the performance of individuals and populations of the invasive plant Verbascum thapsus differs between its native and non-native ranges, across climate gradients, and in response to its position in a globalscaled niche model.Location India (Kashmir) and Switzerland (native range) and Australia and USA (Hawaii, Montana and Oregon) (non-native range). MethodsWe measured population characteristics (density of flowering individuals, population size), plant traits (plant height, number of flowering branches) and seed germination for 50 populations of V. thapsus growing along elevational gradients in six mountain regions around the world (two in the native range, and four in the non-native range). We fitted linear regression models to determine the relationship of plant and population level performance variables to range, region, climate and probability of occurrence from a global niche model. ResultsPlant height, number of flowering branches and population density of V. thapsus did not differ consistently between the native and non-native ranges, but the area covered by populations in the non-native range was on average two orders of magnitude larger than the area of native populations. Within and among regions, individual plant performance traits responded variably to precipitation and mean annual temperature, depending on the climatic range of the observed populations; however, performance was greater for populations that had a greater modelled probability of occurrence. Seed germination under controlled conditions was highest between 20 and 35°C and consistent across populations, although germination at low temperatures was substantially higher for native populations from Kashmir. Main conclusionsThe introduction of V. thapsus to its non-native range is not associated with consistent increases in plant performance. Instead, plant performance is more strongly influenced by position within the climate niche of the species, position along environmental gradients, and climatic or other differences among regions. We demonstrate that individual-level and population-level performance traits can yield different predictors of plant performance. Therefore, future studies comparing plant performance in native and non-native ranges should include both plant and population characteristics and should also sample the target species from multiple regions in both ranges and along environmental gradients that comprehensively represent the niche of the species. 132

Subalpine ecosystems are centres of endemism that are important for biodiversity. However, these areas are under threat from the creation, expansion and continued modification of ski runs, activities that have largely negative effects on wildlife. Despite this threat, research on the impacts of ski runs is limited for reptiles-particularly regarding the value of remnant vegetation retained on ski runs. Here we quantify the effects of habitat loss and fragmentation (i.e., patch size, patch isolation and edge effects) on the abundance of a common subalpine lizard and on thermal regimes (a key determinant of lizard distribution) in an Australian ski resort. The number of lizards observed differed significantly with habitat type (ski runs vs. forested areas) and patch isolation, but not patch size. In addition, the edges of patches supported more lizards than any other habitat type. These patterns of lizard distribution can be explained, in part, by the differing thermal regimes in each habitat. Ski runs had significantly higher ground surface temperatures than any other habitat type, precluding their use for a considerable proportion of the activity period of a lizard. In comparison, edges were characterised by lower temperatures than ski runs, but higher temperatures than the core of forested areas, potentially providing a favourable environment for thermoregulation. Based on our results, we conclude that although modified ski runs have a negative effect on lizards, patches of remnant vegetation retained on ski runs are of value for reptiles and their conservation could help mitigate the negative effects of habitat loss caused by ski run creation.

The critical thermal limits of organisms and the thermal sensitivity of their performance tend to vary predictably across latitudinal gradients. There has been comparatively less investigation into variation in thermal biology with elevation, despite similar gradients in environmental temperatures. To redress this, we examined critical thermal limits (CTmin and CTmax), thermal sensitivity of locomotor performance, and shelter site attributes, in three lizard species that replace one another along a contiguous elevation gradient in south-eastern Australia. The species examined consisted of a highland specialist, Liopholis guthega, mid-elevation species, Liopholis montana, and lowland species, Liopholis whitii. We found similar habitat attributes between the species, but L. guthega predominantly occurred in open habitat, which might reflect a strategy for maximizing exposure to insolation. We found intraspecific variation in lizard thermal traits, most notably in cold tolerance of L. guthega and in both heat and cold tolerance of L. whitii, suggesting population-specific variables acting on thermal physiology rather than a species distribution maintained by distinct thermal tolerances. This study represents one of the few examinations of thermal trait variability within and between species with elevation in a temperate system and provides evidence for thermal physiology driven by adaptation and/or physiological plasticity to local conditions.

Climate change and other global change drivers threaten plant diversity in mountains worldwide. A widely documented response to such environmental modifications is for plant species to change their elevational ranges. Range shifts are often idiosyncratic and difficult to generalize, partly due to variation in sampling methods. There is thus a need for a standardized monitoring strategy that can be applied across mountain regions to assess distribution changes and community turnover of native and non‐native plant species over space and time. Here, we present a conceptually intuitive and standardized protocol developed by the Mountain Invasion Research Network (MIREN) to systematically quantify global patterns of native and non‐native species distributions along elevation gradients and shifts arising from interactive effects of climate change and human disturbance. Usually repeated every five years, surveys consist of 20 sample sites located at equal elevation increments along three replicate roads per sampling region. At each site, three plots extend from the side of a mountain road into surrounding natural vegetation. The protocol has been successfully used in 18 regions worldwide from 2007 to present. Analyses of one point in time already generated some salient results, and revealed region‐specific elevational patterns of native plant species richness, but a globally consistent elevational decline in non‐native species richness. Non‐native plants were also more abundant directly adjacent to road edges, suggesting that disturbed roadsides serve as a vector for invasions into mountains. From the upcoming analyses of time series, even more exciting results can be expected, especially about range shifts. Implementing the protocol in more mountain regions globally would help to generate a more complete picture of how global change alters species distributions. This would inform conservation policy in mountain ecosystems, where some conservation policies remain poorly implemented.