Abstract:

Coastal ecosystems and their endemic taxa are under threat from hurricanes that are increasingly frequent and severe due to climate change–leading to a need to better understand factors associated with species’ resistance (capacity to withstand) and resilience (capacity to rebound) to these storms. The beach mouse species complex ( Peromyscus polionotus spp.) is a representative endangered group of rodents tightly associated with such coastal habitats. We examined track-tube monitoring data of beach mice from Tyndall Air Force Base, Florida, USA, before and after the 2018 strike of Hurricane Michael, a Category 5 hurricane, and again before and after the 2020 strike of Hurricane Sally, a Category 2 hurricane. We applied dynamic occupancy models to track-tube survey data to assess environmental factors associated with beach mouse initial occupancy and local extinction following Hurricane Michael. Beach mice exhibited high probabilities of detection and initial occupancy across most sites and all representative habitats before Hurricane Michael. Dynamic models revealed that local extinction probabilities of beach mice decreased with increasing elevation and dune habitat, followed by grassland, and scrub–highlighting high elevation dune as the primary driver of beach mouse resistance to storms. Extinction probability was not related to other factors like plant species percent cover or proximity to storm strike. Beach mice occurred at 100% of track-tubes before and after Hurricane Sally. Beach mice are adapted to persist in dynamic coastal environments with regular hurricane strikes, as evidenced by their resistance and resilience following Hurricane Michael to reach 100% occupancy with high resistance to the weaker Hurricane Sally. However, as hurricanes become stronger and more frequent with global change, isolated populations of beach mice may be more susceptible to local extinction with the corresponding loss of elevation and dunes. High elevation, particularly in dune habitats, is an important mediator of resistance and resilience to hurricane impacts and should be considered in habitat restoration and reintroduction strategies, especially if relative elevation decreases with sea-level rise.