PS 47-125 - Water-works? Effects of hydrologic restoration on the foraging behavior of the bat community of southwest Florida with particular focus on the endangered Florida bonneted bat

Background/Question/Methods

Wetlands provide critical foraging habitat for bats, but over half of wetlands worldwide

have been degraded or destroyed. Although wetland restoration efforts have recently become more common, little is known about short-term and long-term impacts on bats. Studying these effects is key to understanding how bat communities may respond to these changes. This is particularly important for the endangered Florida bonneted bat (Eumops floridanus), given that much of the species’ geographic range is covered in wetlands that face increasing threats from development and sea level rise. We investigated the impacts of a large-scale hydrologic restoration project expected to affect over 2.5 million acres of wetlands and estuaries in the Florida Everglades. We conducted acoustic surveys at 194 detector sites in 2020 and 2021 and performed telemetry efforts to locate roosts. Detectors recorded at each site for 16 total nights during 4 distinct sample periods spanning the dry and wet seasons. Sites were randomly stratified across a restoration gradient and compared with reference areas. Hydrologic and vegetation metrics were measured at each site to investigate drivers of bat activity in the context of wetland restoration. Acoustic files were classified in Kaleidoscope Pro and all Florida bonneted bat calls were manually verified.

Results/Conclusions

Using exploratory analyses, ordination techniques, and generalized linear mixed models, we describe patterns of bat activity relative to restoration categories and the relative importance of hydrologic and vegetative characteristics in driving habitat selection by Florida bonneted bats and the greater bat community. Preliminary analyses indicate that foraging of all species combined is significantly impacted by the restoration status and vegetation community of acoustic detection sites and the bat community appears to be selecting for the reference sites adjacent to the restoration gradient. Foraging patterns of Florida bonneted bats do not appear to be strongly influenced by restoration category, although all roosts discovered through mist-netting and telemetry were found in reference sites. Foraging habitat selection for this species is likely driven by complex interactions between a number of habitat features including proximity to water, habitat structure, and vegetation community. Insights from this study will inform immediate management decisions for this endangered species, enhance specific management of all bat species in southwest Florida, and contribute to our understanding of how bats more broadly select for foraging habitat and are influenced by hydrologic and subsequent vegetative changes in wetlands.