6 research outputs found

    Managing ski resorts to improve biodiversity conservation: Australian reptiles as a case study

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    Alpine/subalpine environments are diverse systems that support many endemic species. Worldwide, these ecosystems are under threat from ski resort disturbances - even in areas broadly designated for biodiversity conservation. The effects of ski resorts on reptiles are largely unknown, making it difficult to implement effective conservation actions. Many ski resorts do not currently address the needs of reptiles, even those listed as threatened, in their management plans. If reptiles are to continue inhabiting ski resorts in Australia, strategies must be implemented that target their conservation. To begin to address this problem, we summarise current research investigating the effects of ski resorts on reptiles. Based on this information, we recommend strategies that will enhance the conservation of reptiles in areas affected by ski-related disturbances. Suggested strategies include (i) restricting intensive disturbances to already highly modified areas of Australian ski resorts, (ii) avoiding disturbance of remaining native vegetation and structural complexity in ski resorts and (iii) re-establishing structural complexity at highly modified sites through revegetation programmes, or through the cessation of mowing during peak reptile activity periods. While these strategies are designed to facilitate the persistence of reptiles in ski resorts, their long-term success can only be evaluated by monitoring their effectiveness. © 2014 Ecological Society of Australia and Wiley Publishing Asia Pty Ltd

    The impacts of ski resorts on reptiles: A natural experiment

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    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. © 2013 The Zoological Society of London

    Designing for conservation outcomes: The value of remnant habitat for reptiles on ski runs in subalpine landscapes

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    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. © 2014 Springer Science+Business Media Dordrecht

    An experiment to test key hypotheses of the drivers of reptile distribution in subalpine ski resorts

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    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. © 2013 The Authors. Journal of Applied Ecology © 2013 British Ecological Society

    Nailfold Capillary Abnormalities in Primary Open-Angle Glaucoma: A Multisite Study.

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    PURPOSE: There is considerable evidence for systemic vascular dysfunction in primary open-angle glaucoma (POAG). We performed nailfold capillary video microscopy to observe directly the nature of nonocular microvasculature abnormalities in POAG. METHODS: We enrolled 199 POAG patients and 124 control subjects from four sites. We used JH-1004 capillaroscopes to perform nailfold capillary video microscopy on the fourth and fifth digits of each subject's nondominant hand. Videos were evaluated for hemorrhages, dilated capillary loops > 50 μm, and avascular zones > 100 μm by graders masked to case status. Multivariable odds ratios (ORs) and 95% confidence intervals (CIs) for POAG were obtained by means of logistic regression analyses that were applied to data from all cases and controls. Corresponding estimates of moderate or severe POAG versus mild POAG (based on the Hodapp-Anderson-Parrish scale) were obtained among cases only. RESULTS: After controlling for demographic factors, family history of glaucoma, systemic diseases, and use of anticoagulation and antiplatelet therapy, for each 100 nailfold capillaries assessed, all types of microvascular abnormalities were significantly associated with POAG. Specifically, the presence of any dilated capillaries (OR = 2.9; 95% CI, 1.6-5.6), avascular zones (OR = 4.4; 95% CI, 1.7-11.3) and hemorrhages (OR = 12.2; 95% CI, 5.9-25.1) were associated with POAG. Among cases, the frequency of microvascular abnormalities was not associated with glaucoma severity (P ≥ 0.43). CONCLUSIONS: These data provided support for nonocular capillary bed abnormalities in POAG. Comparable vascular abnormalities in the optic nerve may render it susceptible to glaucomatous damage
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