Glacier National Park Bat Inventory and Monitoring Project

Bate, Lisa

Summary Report 2011-2014 We confirmed the presence of nine bat species in Glacier National Park (GNP): Little brown bat, Long-eared bat, Long-legged bat, California Myotis, Yuma Myotis, Big Brown Bat, Eastern Red Bat, Silver-haired Bat, and the Hoary Bat. As a result of these surveys, we added three new species to Glacier’s mammal list: California, and Yuma Myotis, and the Eastern Red Bat. Our findings contributed to range expansions for each of these three new species. During 49 trapping sessions from 2011 through 2014, we trapped and processed bats at 41 different locations throughout GNP. We processed a total of 764 individuals and caught an average of 15.6 bats per night. This included nights when we did not catch any bats. Poor capture success appeared to be weather related. No bats showed signs of White-nose Syndrome (WNS). In addition to mist-netting surveys, we conducted night-time acoustic surveys at 85 different locations within 31 grid cells within GNP over the past four years. We recorded over 57,000 bat passes during warm-season months (May-September). Although we never captured an Eastern Red Bat in Glacier, we recorded 131 bat passes at 22 percent (n = 19) of our detector sites during our acoustic surveys. All were east of the divide. Our acoustic evidence was further supported by the capture of 13 Eastern Red Bats just north in Waterton Lakes National Park (WLNP). We confirmed all but the Hoary and Eastern Red Bats as breeding residents in GNP. We examined 25 structures in GNP for bat presence from 2011 through 2014; sixteen of these structures were confirmed as roost sites. We confirmed the presence of bats at five winter detector sites confirming that bats hibernate on the both the east and west sides of GNP. We also confirmed bat use in three caves, yet it is still unknown whether these structures are used as hibernacula. Recommendations are made for continuing inventory efforts to determine if additional species reside in GNP. We also outline long-term monitoring plans to learn more about the timing and travel corridors for migratory bats, and efforts to locate and monitor bat activity and roost sites of bats susceptible to WNS.

Glacier National Park Bat Inventory and Monitoring Project

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