Midwest Fish & Wildlife Conference 2017

AUTHORS: Jacquelyn Dearborn, University of Missouri; Derek Corcoran Barrios, University of Missouri; Elisabeth Webb, USGS Missouri Cooperative Fisheries and Wildlife Research Unit; Sybill Amelon, USFS Northern Research Station; Shauna Marquardt, USFWS Missouri Ecological Services Field Office

ABSTRACT: Within the last century, approximately 96% of bottomland hardwood forests in the Mississippi Alluvial Valley have been lost as a result of wide-scale anthropogenic land use changes. Mingo and Cypress Creek National Wildlife Refuges contain some of the last remaining tracts of this ecotype in that region. Due to the characterization of bottomland hardwoods as prime roosting habitat for Myotis species, including the federally endangered Myotis sodalis, it is important to determine which habitat types within the refuges are utilized by Myotis species. This will enable refuge managers to better manage their lands for Myotis species, in conjunction with other wildlife. During summer 2015, nine sites were randomly selected in habitats characterized as cropland, herbaceous wetland, and wooded wetland on each refuge. In each habitat type, we placed three Anabat II detectors on raised platforms constructed out of polyvinyl chloride (PVC). Detectors were deployed for three consecutive nights, and then moved to the next site in each habitat type. Throughout summer 2015, all nine sites per habitat type per refuge were surveyed for three detector nights. Habitat characteristics including stand density, water depth, distance to water and distance to road, were measured at each site. All calls were analyzed manually using Analook software, and Myotis calls were identified. We evaluated Myotis species detection and occupancy probabilities in relation to habitat covariates in a single-season occupancy modeling framework using program DiversityOccupancy in R. The top model included stand density, showing a positive relationship between stand density and occupancy by Myotis species. Our results indicate that wooded wetlands are more likely to provide useful foraging habitat for Myotis species, suggesting that managing for more bottomland hardwood forests would be beneficial for Indiana bats as well as the other Myotis species.