Kira Hefty Abstracts
Kira Hefty
Ph.D. Candidate
Applied Intercultural Arts Research GIDP
8th International Squirrel Colloquium
Galway, Ireland
June 4-8, 2018
Southwest Florida contains a unique mosaic of pine upland, hardwood, mangrove swamp, and freshwater cypress swamp that has allowed for the emergence of some of the highest numbers of endemic wildlife species in the United States. Big Cypress fox squirrels (Sciurus niger avicennia: BCFS) are currently listed as a Species of Greatest Conservation Concern in Florida’s Wildlife Legacy Initiative Wildlife Action Plan (SAP 2012). We used non-invasive field sampling techniques and spatial analysis methods to understand how BCFS are using these threatened vegetative communities and which conditions within them influence BCFS use. Wildlife camera data and robust vegetative surveys were used to inform occupancy analysis and resource selection of BCFS on 372,000 ha of public land in southwest Florida. Habitat connectivity analysis was also used to identify restrictions to individual movement and overall population distribution. Results indicate that occupancy is largely influenced by high overstory canopy connectedness, low understory density, and the presence of important food and nesting materials. These important features were patchily distributed within and between preserves, separated by barriers to individual movement. These results indicate a need for more cohesive and targeted land management to assist the recovery of this important subspecies.
Abstract for Lay Audience
Southwest Florida contains a unique mosaic of pine upland, hardwood, mangrove swamp, and freshwater cypress swamp that allowed for the emergence of some of the highest numbers of locally evolved wildlife species and subspecies in the United States. Additionally, with one of the fastest growing human populations, these ecosystems are threatened by significant and ongoing habitat fragmentation, habitat degradation due to fire suppression, terrestrial oil exploration and extraction, changes in hydrologic patterns due to extensive agriculture and urban development, disease, and widespread invasive species such as the Burmese python. These threats are currently known to have caused decline in several species, however, the extent of the decline is currently limited by lack of basic ecological knowledge of many of the species affected.
Our research focuses on using an arboreal squirrel subspecies native to these unique and threatened ecosystems as an indicator of overall ecosystem function. Big Cypress fox squirrels (Sciurus niger avicennia: BCFS) are currently listed as a Species of Greatest Conservation Concern in Florida’s Wildlife Legacy Initiative Wildlife Action Plan (SAP 2012). How BCFS are using these threatened vegetative communities and what conditions within them are important to BCFS remains unknown.
We used wildlife cameras and hair snare tubes to detect BCFS and other wildlife species on 213 plots on public land in southwest Florida. At each plot, robust vegetative surveys were conducted to better understand which plot-level vegetative characteristics influence occurrence of BCFS. In the office, these data were combined with spatial analysis techniques in ArcGIS to inform occupancy of BCFS at the landscape-scale. Spatial analysis allowed us to indicate overall potential extent of occurrence as well as specific areas of occurrence of BCFS in southwest Florida. Further analysis using circuit theory in ArcGIS allowed us to identify which features— such as roads—on the landscape influence habitat connectivity and, therefore, species distribution.
Vegetative structure, such as overstory tree connectedness, was an important predictor of BCFS occupancy. Vegetative composition and landscape-scale distribution of specific vegetative species, such as cypress, was also an important predictor of BCFS occupancy. Features that indicated greater probability of species occurrence were patchily distributed at the landscape scale and often separated by anthropogenic features restrictive to individual movement, such as large highways with fences and interstates. Our results indicate a greater need for cohesive land management across multiple local, state, and federal agencies to aid in the landscape-level conservation and recovery of this important species as well as other species that depend on these fragmented vegetative.