Abstract
The primary goal of the study was to collect acoustic information on activity levels of bats during nocturnal hours, particularly during spring and fall migration. Specifically, our objectives were to: (1) collect baseline information on levels of bat activity (e.g.,bat passes/detector-night) for migratory tree roosting bats (e.g., hoary and big brown/silver-haired bats) and other bat species, and (2) examine spatial (height and location) and temporal (nightly and seasonal) variations in bat activity.
We conducted bat acoustic monitoring for 217 nights between 15 April and 17 November 2008 at the proposed Coyote Crest Wind Power in Lewis and Pacific Counties, Washington. Each night we conducted bat acoustic monitoring for 10.5–16 hours/night (1h < sunset to 1h > sunrise).