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

Abstract

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 Conservation Value of Small Fragments For Atlantic Forest Reptiles

“…For instance, smaller fragments are more susceptible to edge effects, and a greater proportion of total area is affected by climatic and biotic influences from the surrounding matrix, resulting in modified microhabitats, which can significantly affect the occurrence of lizards in tropical forests (Garda et al 2013). Fragment edges have been shown to harbor more squamate species at higher densities compared to forest interior (Rubio & Simonetti 2011, Sato et al 2014, Carvajal-Cogollo & Urbina-Cardona 2015. In our study, we sampled only fragment centroids, and in smaller fragments pitfalls were closer to fragments edges.…”

“…Fragment edges have been shown to harbor more squamate species at higher densities compared to forest interior (Rubio & Simonetti , Sato et al . , Carvajal‐Cogollo & Urbina‐Cardona ). In our study, we sampled only fragment centroids, and in smaller fragments pitfalls were closer to fragments edges.…”

Temperature influences resource use by chestnut‐bellied scaled quail

“…, Sato et al. , Smith et al. , Ahnesjö and Forsman ) and have been less widely used in studies of endotherms such as ground‐dwelling mammals (Sharpe and Van Horne ) and desert birds (Tieleman et al.…”

“…As we predicted, ground surface temperature was a better predictor of the probability of use of a location by scaled quail even though use of black globes is the standard approach used when modeling the thermal environment of animals, particularly quails (Guthery et al 2005, Carroll et al 2015a. Ground surface temperatures have been widely used in habitat selection studies of ectotherms (Kapfer et al 2008, Sato et al 2014, Smith et al 2015b, Ahnesj€ o and Forsman 2006 and have been less widely used in studies of endotherms such as ground-dwelling mammals (Sharpe and Van Horne 1999) and desert birds (Tieleman et al 2008). For northern bobwhites, a combination of ground surface temperature and black globe temperature was a better predictor of the relative probability of use than either of the temperature measurements alone (Olsen et al 2018).…”

Allopatric divergence drives the genetic structuring of an endangered alpine endemic lizard with a sky‐island distribution

“…In habitat specialist montane species with characteristically poor dispersal ability (McCain & Colwell, ), this current isolation inhibits migration and gene flow, promoting inbreeding and genetic drift (Sumner, ; Haines et al ., ). Consequently, this homogenizes genetic diversity within sky‐islands (Browne & Ferree, ), while producing genetic structure among islands (Mitrovski et al ., ), increasing rates of both diversification and extinction (Hedrick & Kalinowski, ; Koumoundouros et al ., ; Sato et al ., ). In extreme cases, this lack of contemporary connectivity can erode genetic diversity sufficiently within fragments to reduce population‐level fitness, which elevates extinction risk (Maron et al ., ).…”