Bats are a taxon of concern throughout North America and little was previously known about their presence in the Baltimore, a ‘shrinking’ city that straddles the Piedmont and Coastal Plain regions. Within Baltimore, there are over 2,000 ha of vacant lots, and the extent to which bats may use these disregarded greenspaces has not been investigated. After discovering at least six bat species were present in Baltimore, we began investigating environmental and socioeconomic factors in and surrounding vacant lots with the purpose of determining which variables best predict bat species richness and activity. Between May 2017 and April 2018, passive acoustic monitoring was conducted for six, three-night sessions at 16 randomly selected vacant lots. Site-scale variables such as canopy cover, ground cover height, and number of streetlights present were measured. Shapefiles of neighborhood and landscape-scale variables (size, percent forest cover, canopy cover, vacant housing density, road density, and 2010 census data) were obtained and analyzed using ArcMap.
Results/Conclusions
Over 35,000 sequences were recorded. Initial results show detections of the same six species, with most activity coming from big brown bats (Eptesicus fuscus). Several sites appear to have distinct communities with varying activity levels from four other species (Lasiurus borealis, L. cinereus, Lasionycteris noctivagans, and (Nycticeius humeralis), with only one site having activity from Perimyotis tricolor. Mean nightly bat activity and species richness was highest in summer with some sites recording over 500 sequences in a night. Mean nightly bat activity and species richness was lowest in winter, with no more than two species being recorded; in addition, some activity was recorded in sub-zero temperatures prior to a major storm. We will be sharing our initial results on GIS analysis and possibly initial modeling results. In the future, we hope to investigate historical landscape data and Baltimore’s racial past as possible predictors of current bat presence.