A regional scale assessment of habitat selection and home range of the eastern rat snake in pine-dominated forests

An animal's spatial ecology may provide insight into how resources are distributed or potentially limiting across its home range. Some species with broad geographic distributions may exhibit intraspecific variation in space use among populations given the spectrum of available habitat across their range. Animals may need to move further in habitats with limited resources thereby lowering survival. Species, like the eastern rat snake (Pantherophis alleghaniensis), occur throughout the eastern USA and are thought to be strongly tied to hardwood forests. However, their occurrence in pine-dominated forests in the southeastern USA suggests they have broader habitat requirements than previously noted. Our objective was to investigate patterns of habitat use and spatial ecology for eastern rat snakes across multiple pine-dominated forests in Southern Georgia and Northern Florida to capture regional differences in eastern rat snake resource use. We examined home range and habitat use at multiple spatial scales for 30 radio-telemetered snakes from three sites; one in Georgia (Pebble Hill) and Florida (Tall Timbers) during 2004-2005 and one more northern site in Georgia (Ichauway) during 2010-2012. Snakes tracked on Ichauway had a mean home range size that was 3.9 times larger (95% Mean Convex Polygon [MCP], 13.6 ± 8.2 ha) than the estimate for Tall Timbers (3.5 ± 3.2 ha) and 2.6 times larger than the estimate for Pebble Hill (5.3 ± 3.2 ha). Snakes at all three sites selected primarily open edge and pine habitat at the landscape scale and were most likely to be found in large, mature oak trees (Quercus spp.). At Ichauway, hardwood removal activities associated with longleaf pine (Pinus palustris) restoration reduced the number of hardwood trees per hectare by 33% in hardwood removal areas from 1998 to 2014. This management approach included limiting suitable large oak trees that rat snakes use and may help explain the variation in home range size and the number of snakes captured at Ichauway (n = 14) compared to the other two sites (Tall Timbers, n = 154, Pebble Hill, n = 127).