An exploratory study of northern long-eared bats on Nantucket

Report submitted in fulfillment of a 2016 Nantucket Biodiversity Initiative grant

The federally threatened northern long-eared bat (Myotis septentrionalis) appears to be persisting in the Cape and Islands region, despite dramatic population declines across the Northeast associated with the spread of White Nose Syndrome. Acoustic data and a dead bat specimen found on Nantucket in 2015 suggested there might be remnant populations of the species on the island. I worked with the Nantucket Conservation Foundation in 2016 to conduct a small-scale mist-netting and radio-tracking study, in an effort to confirm the presence of northern long-eared bat colonies on the island. We successfully captured lactating females and healthy juvenile northern long-eared bats in July, and tracked one female to a maternity colony comprising at least 11 individuals. In October, we captured an adult male northern long-eared bat, which we tracked to a fall roost and potential hibernation site. We tagged three of the four additional individuals found at this site, and deployed data loggers to record temperature and humidity. Nantucket appears to be supporting at least one healthy colony of northern long-eared bats, which could be due in part to bats remaining on-island throughout the winter.