Fire, flooding, and felids: Deer and puma spatial ecology and predator-prey interactions in dynamic, subtropical wildlands

Cyclic and extreme ecological disturbances have the capacity to alter resources and thereby animal populations. Interactions between disturbance and resource availability can influence predator-prey interactions. Predator-prey responses to ecological disturbance may be more pronounced in herbivores and their predators as herbivores track food resources that are often augmented by ecological disturbance. My objective with this dissertation was to examine how various forms of ecological disturbance influence predator-prey interactions through the lens of a case study – white-tailed deer (Odocoileus virginianus) and Florida panther (Puma concolor coryi) in southwestern Florida public and conservation lands. I quantified species-specific behavior of deer to an extreme disturbance event (i.e., Hurricane Irma), examined behavior of females with different fate outcomes to varied ecological disturbances and predation, investigated how ecological disturbance mediates the influence of human disturbance on predator-prey interactions, and quantified deer spatial ecology in response to fire, hydrology, panther and human activity. I found that deer behaviorally mediated the negative fitness impacts of Hurricane Irma. Further, I found that female deer with different fate outcomes selected areas of different ecological disturbance and the ecological disturbance type conferred different fitness costs (through differences in predation risk). Finally, I found that South Florida deer utilize diurnal times when humans are the most active to temporally reduce predation risk as panthers were more nocturnal in response to humans. My work here suggests that ecological disturbance regimes have the capacity to influence predator-prey interactions through nuanced mechanisms. Outcomes of these nuanced species-specific and predator-prey responses should be examined further. More practically, if disturbance influences aspects of animal fitness, a deeper understanding of species-specific and predator-prey responses to disturbance will improve management and conservation efforts as some regimes can be manipulated (e.g., prescribed fire). More broadly, consideration of ecological disturbance when examining predator-prey interactions may yield novel insight that deviates from predictions based on inference suggested in systems without disturbance. Highlighting nuanced predator-prey interactions mediated by ecological disturbances will improve predictions regarding species and community responses to global changes such as climate change and ecological restoration.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Fisheries and Wildlife Science

Department dc:contributor.department

Fish and Wildlife Conservation

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2021

Author dc:creator

• Abernathy, Heather N.

Chair dc:contributor.committeechair

• Cherry, Michael J.

Committee members dc:contributor.committeemember

• Wynne, Randolph H.
• Chandler, Richard B.
• Kelly, Marcella J.

• predator-prey ecology
• animal behavior
• trait-mediated indirect interactions
• ecological disturbance
• human disturbance
• fire
• hydrology
• puma
• white-tailed deer
• South Florida

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

vt_gsexam:29439

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/112023