Meeting Abstract

P1.26  Saturday, Jan. 4 15:30  Summer bat populations in the White-nosed era: implications for future survival. HERMANSON, JW*; MACAYEAL, LC; MCDONALD, C; GARY, G; WAXMAN, L; ROONEY, P; STONE, M; BUCKLES, E; CURTIS, PD; LANIEWICZ, BR; Cornell Univ., Ithaca NY; NYS Dept. of Health,CCH,BCDC, Albany NY jwh6@cornell.edu

Bat populations in the northeastern United States have declined dramatically since the recognition of White-nosed Syndrome (WNS) in a hibernation roost in 2006. Little brown bats (Myotis lucifugus) were the most common bat species in New York, but have declined precipitously. Because of the economic and biologic impact of bats, biologists have worked to document the spread of WNS and to address its mode of transmission. The causative agent of WNS is a cold-loving fungus, Pseudogymnoascus destructans. Nearly 7 million bats have died as a result of WNS. High mortality has been documented at numerous winter hibernation sites and there has been a progression of the disease to other hibernation sites across the United States. Maternity roosts populations were studied with direct visual counts and infrared illuminated video counts of the evening outflights. We have assessed summer populations of little brown bats at traditional hibernation sites in central New York and have documented a 80%, 90% and a 93.4% reduction (in the past three summers, respectively) in the expected number of female bats occupying 8 maternity roosts in the central New York region. Differences in stability of populations between roosts suggest that some populations have been isolated from, or are somewhat resistant to the impacts of WNS. Two of our study sites retained at least 20% of the population size seen in the pre-White nosed era, while one of our study sites experienced a total loss of little brown bats, and two others at least a 99% reduction of population size. We assess the use of human-built structures such as barns and out-buildings, as well as bat boxes in population stability. Supported in part by a grant from Hatch funds (NYC-435482).