Date of Award
5-1-2024
Degree Name
Master of Science
Department
Forestry
First Advisor
NIELSEN, CLAYTON
Second Advisor
GRONINGER, JOHN
Abstract
Land cover conversion has resulted in severe habitat fragmentation, degradation, and loss in bottomland hardwood (BLH) forests throughout the Lower Mississippi Alluvial Valley. BLH forests in southern Illinois are home to diverse wildlife communities, many of which are of conservation concern and utilize BLH habitat year-round or during migration and/or breeding. Efforts in recent years have focused on ecological restoration and reforestation to enhance BLH ecosystem structure, function, diversity, and wildlife-habitat conditions. Due to the complexity of BLH habitat and varied inter- and intra-taxa niches, it is often difficult to develop plans aimed to improve wildlife habitat. However, it is important to determine the habitat characteristics and conditions that influence occupancy across taxa to effectively monitor and manage the BLH wildlife community. I modeled occupancy of the swamp rabbit (Sylvilagus aquaticus), 9 avian species, and 2 herpetofauna species. The swamp rabbit was chosen due to its significance as a BLH specialist sensitive to disturbance pattern changes and habitat loss. Results highlight the importance of considering seasonality and flood conditions for species detection in BLH systems. Landscape-level variables describing the spatial arrangement and distribution of habitat (i.e., distance to road, distance to upland, land cover type and forest cover) provided the most support across all modeled taxa. Site-level variables (i.e., woody stem density and ground cover types) were also supported, but with varied results. Distance to road was the only variable with a significant influence on occupancy across all modeled taxa. Forest cover was the most supported occupancy variable across modeled avian species. These results allude to the importance of improving BLH habitat availability and connectivity across the landscape. However, my results also suggest that local-level habitat heterogeneity is important to BLH wildlife and influenced by hydrological patterns. Future research should develop techniques that measure flooding duration, depth, and frequency to better understand occupancy dynamics of BLH wildlife. Additionally, monitoring indicator species may also improve the efficiency and effectiveness of BLH wildlife-habitat management.
Access
This thesis is Open Access and may be downloaded by anyone.