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Context Understanding what characteristics influence retreat-site selection by fauna is critical for both habitat management and species conservation. Despite the documented ecological values of surface rocks, there is limited knowledge of the attributes of surface rock that contribute to their use in agricultural landscapes or during winter months when reptiles are brumating, activity patterns are reduced, and sheltering individuals are most vulnerable to disturbance. Objectives We surveyed reptiles sheltering beneath surface rocks in grazing farms in south-eastern Australia to address two questions: (i) What landscape factors influence the occurrence of reptiles over austral winter? (ii) What physical and thermal factors influence retreat-site selection? Methods We surveyed 14 sites, with three plots per site, stratified across a gradient of canopy cover. We measured landscape attributes of surveyed sites and thermal and physical characteristics of individual surface rocks to quantify relationships between the occurrence of reptiles in the landscape and the properties of retreats selected. Results We found that relatively small patches of surface rock can support high reptile numbers, with density estimates up to of 208 individuals per hectare. Reptile abundance was positively associated with increased elevation and limited canopy cover. Reptiles selected smaller rocks with high surface area to volume ratio, were minimally embedded in the soil, and rocks supporting few invertebrates. Conclusions Conserving cryptozoic reptiles in agricultural landscapes can be enhanced through the appropriate management and retention of surface rock. We discuss implications for reptile conservation and surface rock management in agricultural landscapes.

Microhabitat characteristics can be used as a proxy to predict the community structure of associated organisms and evaluate their vulnerability to habitat degradation. Microhabitat-specific and ectothermic taxa (like many reptiles) are among the best models to study responses to changing habitats and climate. We examined the niche breadth and guild structure of reptiles from Agasthyamalai Hills in the southern Western Ghats of India based on microhabitat use data. We recorded a total of 47 reptile species from 1,554 observations comprising two major orders and 11 families. Niche breadth analysis revealed that 45% of reptiles are microhabitat specialists, indicating the importance of protecting their habitats with all structural attributes. Cluster analysis grouped reptile species into four major guilds based on microhabitat preferences. The forest floor-dwelling guild was the largest group with 25 species, followed by the semi-arboreal guild with 12 species. The floor-dwelling guild also exhibited both the highest number of microhabitat specialists (n = 11) and globally threatened species (n = 3), highlighting the need for preserving ground cover characteristics such as leaf litter, boulders, and open ground for conserving reptiles in the region. Considering the microhabitat specializations within the community, we recommend a dynamic approach to monitor abundance, diversity, and habitat quality across the Agasthyamalai landscape to better conserve its rich reptile diversity.

Arboreal lizards, especially species that inhabit flood-prone environments, have been poorly surveyed worldwide. We examined spatiotemporal patterns in arboreal lizard abundance and factors driving detection rates in floodplain environments using artificial bark covers, a non-destructive and cost-effective survey method. In total, 112 flexible, closed-cell foam bark covers were installed on eucalypt trees in 13 wetlands in the Murrumbidgee River floodplain of southern New South Wales, Australia, stratified by two inundation frequency treatments. Of four arboreal lizard species detected, the southern marbled gecko (Christinus marmoratus) (n = 41) and the tree dtella (Gehyra versicolor) (n = 8) were restricted to the mid-Murrumbidgee region, whereas the crevice skink (Egernia striolata) (n = 19) was restricted to the lower-Murrumbidgee region and did not co-occur with either gecko species. Mean detection rates of lizard species did not differ between frequently and infrequently inundated treatments but their abundance beneath covers varied significantly by month. For all detected lizard species, the presence/absence of the arachnid Holconia murrayensis represented a significant variable in explaining lizard occurrence patterns, particularly that of C. marmoratus. Artificial bark covers are a useful survey method for collecting distribution, abundance, and occupancy data on floodplain reptiles, although detection rates can be affected by the month, predator–prey interactions, and survey effort. Adopting passive, non-destructive reptile survey methods would greatly improve our knowledge of species’ distributions and abundance patterns in vegetation communities subject to disturbance events.

Feeding observations in free-ranging nocturnal snakes are rare, primarily due to their cryptic behaviour and activity patterns. We describe a feeding observation in a free-ranging Grey Snake Hemiaspis damelii in the Murrumbidgee catchment, southern NSW. Hemiaspis damelii is an anurophagous (frog-eating) specialist, yet the feeding ecology and prey of H. damelii in southern NSW is unknown. Our observations provide the first recorded prey items from the southern parts of its range and highlight a potential feeding strategy used by small anurophagous elapids.

Context The amount and configuration of habitat are independent but tightly linked landscape characteristics which are often confounded in ecological studies. Differentiating the effects of each characteristic is critical for conservation, because the mechanisms by which they influence populations are distinct. While studies that have measured the effects of habitat amount and configuration separately have often found the former to be more important, a subset of these studies suggest habitat configuration can be vital to a species when habitat amount is low (10–30%). Objectives We aimed to test the independent effects of habitat amount and configuration on the occupancy and abundance of an endangered marsupial predator, the northern quoll (Dasyurus hallucatus), which persists in naturally fragmented rocky landscapes, in which habitat amount is naturally low (i.e. typically Methods Northern quolls were surveyed across 22 study landscapes that were deliberately selected such that habitat amount and configuration were uncorrelated. Northern quoll occupancy and abundance was estimated at each landscape using data collected from remote sensing cameras, and a combination of occupancy and n-mixture models. Results Spatial configuration of rocky habitats was more important than the amount of habitat when predicting quoll occupancy and abundance; northern quolls were less abundant in landscapes that were more fragmented. In addition, northern quolls favoured areas that were topographically rugged and received more rainfall. Conclusions Our results support the hypothesis that the effects of habitat configuration can be strongest when habitat amount is low, and underscore the importance of aggregated patches of rocky outcrops for northern quoll conservation. The subdivision of rocky habitat, for instance through construction of mines or mining infrastructure (e.g. road, rail lines), is likely to have negative impacts on northern quoll populations.