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We initiated the citizen science-based Alaska Bat Monitoring Project in 2004 to investigate the distribution, habitat use, and seasonal ecology of the Little Brown Myotis in Southcentral, Central, and Western Alaska. As of 2012, we received reports of bats from 252 unique locations across the focus area, including Kotzebue, White Mountain, Saint Michael, and the Semidi Islands, which represent significant range extensions for bats in the state. Ninety-seven percent of 111 roosts were located in human structures. Maternity colonies were identified in 48 locations, all in human structures. The majority of observations were reported in late July, August, and September, but we received observations every month of the year. We received reports of bats in 25 unique locations during the winter period from October to April. Winter bats were all associated with buildings unless observed flying outdoors; no hibernacula in natural substrates were documented. Timing and locations of winter observations imply that bats in the most northerly areas are likely non-migratory and overwinter in human structures, while winter observations in Southcentral Alaska suggest both migratory and non-migratory behavior. Despite the limitations and bias inherent in the data set, these reports represent a significant contribution to our understanding of the distribution and ecology of the Little Brown Myotis in Alaska and provide a basis for future directed research efforts. [ABSTRACT FROM AUTHOR]

Although 5 species of bats have been documented in Southeast Alaska, information on species not of the genus Myotis is derived solely from 4 specimens of the Silver-haired Bat (Lasionycteris noctivagans). We acoustically monitored for bat species that produce low frequency echolocation calls (<30 kHz minimum frequency), specifically Hoary Bat (Lasiurus cinereus), Silver-haired Bat, and Big Brown Bat (Eptesicus fuscus) at 40 sites in 16 locations across Southeast Alaska from 2011 to 2013 using passive bat detectors. The Hoary Bat was not previously known from Alaska, but we recorded 25 call files of this species (of 26,151 low frequency bat files) at 5 sites in northern Southeast Alaska (4 mainland sites and 1 site on Chichagof Island); an additional 110 call files were classified as probable Hoary Bat, but were ambiguous. We recorded 3075 call files that contained echolocation calls diagnostic of Silver-haired Bats; no files had characteristics diagnostic of Big Brown Bats. The rest of the low frequency recordings were identified as probable Silver-haired Bat calls, although Big Brown Bats cannot be ruled out due to the extensive overlap of acoustic characteristics between these 2 species. We recorded Hoary Bats almost exclusively during the autumn migration period. By contrast, Silver-haired Bats were detected throughout the summer active season, indicating at least some individuals are resident in Southeast Alaska. Silver-haired Bat activity was greatest at sites on or near the mainland, with most sites showing peaks of activity in spring, suggesting bats from the interior may be overwintering in the region. Winter recordings suggest Silver-haired Bats (and Big Brown Bats if present) are active to some extent during winter in Southeast Alaska. Understanding the distribution and seasonality of Hoary and Silver-haired Bat activity in Southeast Alaska is a critical 1st step toward identifying their habitat requirements and conservation needs in this region. [ABSTRACT FROM AUTHOR]