Spatial ecology and habitat selection of eastern hognose snakes

Abstract

The eastern hognose snake (Heterodon platirhinos) is a species of conservation concern, especially in the northeastern portion of its range. They remain relatively common at Cape Cod National Seashore, Barnstable County, Massachusetts, USA, where we studied their spatial ecology and habitat selection. We radio‐tracked 17 adult snakes (10 F, 7 M) from May 2009 to November 2011, yielding 765 relocations. We conducted a use‐availability analysis to investigate patterns of microhabitat selection using a subset of snake locations. We conducted a compositional analysis of habitat selection at multiple spatial scales within home ranges using a high‐resolution (1‐m pixel size) vegetation cover map of the study area. Snakes moved frequently and had large home ranges (x¯ = 35.4 ha) relative to other snake species of similar body size but exhibited variation in home range size among individuals (1–209 ha). Movements peaked at different times of year for each sex, and were most different between sexes in fall. In gravid females, movement was significantly greater in the 2‐week post‐oviposition period versus the 2‐week pre‐oviposition period. Estimates of home range and average daily movements (x¯ = 30.1 m/day) were lower than estimates from other studies of eastern hognose snakes, possibly because of a greater density of resources at our study area. Probability of snake habitat use increased with grass and leaf litter and decreased with open soil. Compositional analysis revealed a strong avoidance of open dune areas. A comparison of edge density between use and random locations within home ranges revealed an apparent preference for edge habitat. We recommend that resource managers should limit recreational disturbance to and maintain the patchy mosaic of early successional vegetation with abundant edge to ensure the persistence of appropriate habitat for the species. We identified the timing of peak seasonal movements and recommend that this information be used to help prevent road mortality for this important population. © 2017 The Wildlife Society.

Eastern Hog‐Nosed Snake Habitat Selection at Multiple Spatial Scales in Ontario, Canada

“…The mean MCP home‐range area we calculated for eastern hog‐nosed snakes in Ontario (39 ha, n = 17 snakes) is comparable to most previously reported values for populations in the northeastern United States: 52 ha (LaGory et al 2009), 35 ha (Buchanan et al 2017), 25 ha (Vanek and Wasko 2017), and 19 ha (Akresh et al 2017). Goulet et al (2015) reported larger home ranges, averaging 73 ha, in New Hampshire.…”

“…Construction of minimum convex polygons (MCPs) is the most common method to estimate home ranges (Hansteen et al 1997, Burgman and Fox 2003, Nilsen et al 2008) and is recommended for reptiles (Row and Blouin‐Demers 2006 b ). We calculated MCPs for snakes with ≥15 telemetry locations as recommended by others (LaGory et al 2009, Akresh et al 2017, Buchanan et al 2017).…”

“…Several recent radio‐telemetry studies (involving 6–17 individuals) have focused on habitat selection by hog‐nosed snakes in the northeastern United States (NH, MA, NY). Similar to other species in northeastern North America (Blouin‐Demers and Weatherhead 2001 a , Row and Blouin‐Demers 2006 a , Halliday and Blouin‐Demers 2016, Maddalena et al 2020), common patterns of habitat selection of hog‐nosed snakes include preference for edge habitats (LaGory et al 2009, Buchanan et al 2017, Vanek and Wasko 2017); forest with low canopy cover (Goulet et al 2015, Akresh et al 2017); and open, early‐successional vegetation (LaGory et al 2009, Vanek and Wasko 2017). None of these previous studies on hog‐nosed snakes were conducted in Canada at the northernmost extent of the range of the species where it is listed as threatened by COSEWIC.…”

Habitat association in the critically endangered Mangshan pit viper (Protobothrops mangshanensis), a species endemic to China

“…Previous studies have also revealed that snakes avoided bare ground ( Sperry et al, 2009 ; Baxley, Lipps & Qualls, 2011 ; Gardiner et al, 2015 ). Leaf litter cover can keep the ground temperature relatively stable and provide conditions for thermoregulation ( Buchanan et al, 2017 ). In areas of bare soil, the temperature changes greatly, which may exceed the tolerance limit of snakes.…”

“…Based on a review of the current literature and data from our previous research (Fig. 2), we identified 11 important habitat variables for P. mangshanensis (Baxley, Lipps & Qualls, 2011;Gardiner et al, 2015;Buchanan et al, 2017;Sutton et al, 2017;Sprague & Bateman, 2018). Habitat variables were measured as follows.…”