Seasonal Shifts in Nocturnal Habitat Use by Coastal Bat Species

Sensitivity of bats to land use change depends on their foraging ecology, which varies among species based on ecomorphological traits. Additionally, because prey availability, vegetative clutter, and temperature change throughout the year, some species may display seasonal shifts in their nocturnal habitat use. In the Coastal Plain of South Carolina, USA, the northern long-eared bat (Myotis septentrionalis), southeastern myotis (Myotis austroriparius), tri-colored bat (Perimyotis subflavus), and northern yellow bat (Lasiurus intermedius) are species of conservation concern that are threatened by habitat loss. Our objective was to identify characteristics of habitat used by these species during their nightly active period and compare use between summer and winter. We conducted acoustic surveys at 125 sites during May–August and at 121 of the same 125 sites December–March 2018 and 2019 in upland forests, bottomland forests, fields, ponds, and salt marsh and used occupancy models to assess habitat use. The northern long-eared bat and southeastern myotis (i.e., myotis bats) used sites that were closer to hardwood stands, pine stands, and fresh water year-round. We did not identify any strong predictors of tri-colored bat habitat use in summer, but during winter they used bottomland forests, fields, and ponds more than salt marsh and upland forests. During summer and winter, northern yellow bats used sites close to fresh water and salt marsh. Additionally, during summer they used fields, ponds, and salt marsh more than upland and bottomland forests, but in winter they used bottomland forests, fields, and ponds more than upland forest and salt marsh. Our results highlight important land cover types for bats in this area (e.g., bottomland forests, ponds, and salt marsh), and that habitat use changes between seasons. Accounting for and understanding how habitat use changes throughout the year will inform managers about how critical habitat features may vary in their importance to bats throughout the year. © 2021 The Wildlife Society.