EASTERN RED BAT (LASIURUS BOREALIS) OCCURRENCE IN NORTHERN ALBERTA.

Little is known about the distribution of Eastern Red Bats (Lasiurus borealis) at the northwestern edge of their range. We compiled and examined a data set of Eastern Red Bat capture and acoustic records from northern Alberta to examine their distribution, seasonality, and reproductive status near the edge of their range. Acoustic data suggested widespread but patchy distribution across Alberta. The number of captures of Eastern Red Bats in northern Alberta were similar to those of Hoary Bat (Lasiurus cinereus), suggesting that the species may be more common than previously thought. However, we failed to find evidence of reproduction in female Eastern Red Bats in Alberta. Small sample sizes, timing of surveys or difficulty in recognizing juveniles may explain the apparent lack of reproduction. Similar to Hoary Bats, reproductive adult male Eastern Red Bats have been captured with enlarged testes in northern Alberta in August, suggesting sperm production and possibly the start of breeding is taking place there in late summer. In northern Alberta, acoustic monitoring in early spring provided evidence of migratory bats early in the season. A better understanding of seasonal movement patterns and migration, habitat use, and reproduction of Eastern Red Bats in western Canada will require further study. Regardless, our data provide further evidence that the Eastern Red Bat is a more regular member of the bat fauna of northwestern Canada than previously recognized, which may be a result of an expanding distribution. [ABSTRACT FROM AUTHOR]