Hydrogeomorphology Influences Swamp Rabbit Habitat Selection in Bottomland Hardwood Forests

In the last century, bottomland hardwood (BLH) forests throughout the Lower Mississippi Alluvial Valley in the United States declined >80% and have been degraded because of habitat loss, fragmentation, and altered hydrology. To better understand how current conditions in BLH forest systems influence wildlife and to better manage land use and vegetation, we characterized winter (Dec–Mar) multi-scale habitat selection of 75 radio-marked swamp rabbits (Sylvilagus aquaticus) based on 850 locations in southern Illinois, USA, during 2010–2016. We investigated habitat selection by fitting resource selection functions with generalized linear mixed models based on Euclidean distances (km) to 8 cover types that described hydrogeomorphic conditions. At the second-order scale of selection (home range selection), swamp rabbits were closer to deciduous forest and low-elevation BLH and farther from agriculture, permanent water, shallow BLH, and woody wetland. At the third-order scale of selection (habitat selection within the home range), swamp rabbits selected areas closer to deciduous forest, low BLH, and shallow BLH, and farther from woody wetlands. For the swamp rabbit in Illinois, a BLH specialist at the northern extent of their range, habitat selection is limited to available terrestrial habitat that provides vegetation for food and hiding cover within linear and flood-prone BLH corridors surrounded by agricultural cover types that are largely unsuitable as habitat. Because hydrologic conditions are spatially and temporally dynamic, wildlife managers should focus on providing diverse habitat conditions across elevations that ensure the continuous availability of terrestrial habitat regardless of water level and flooding extent across the BLH landscape. Further reforestation efforts in BLH ecosystems should target current agricultural land on higher elevations adjacent to characteristically flood-prone forest remnants that escaped agricultural clearing due to frequent flooding.