| Lasiurus blossevillii is a tree-roosting bat found throughout the western United States. In California, the species is known to be present year-round in the Central Valley. However, the local seasonal migratory patterns in the state are not well understood. The aim of this study is to examine the migratory patterns of L. blossevillii in Northern California. Using acoustic data, we acquired the activity patterns of L. blossevillii from three different habitat types: an agricultural area in the valley at 60m asl, canyon and ridge oak woodland at 600m, and a pine-juniper forest at 1554m. Long-term acoustic monitoring equipment was placed at each site to record nightly echolocation calls of bats and the recordings were analyzed to identify species using SonoBat software. Lasiurus blossevilli had the highest levels of activity during the months of June and July across all three sites, with the higher elevation pine-juniper forest having the greatest activity. Both of the lower elevation sites retained low levels of activity throughout the winter suggesting temperatures warm enough for occasional foraging. The agricultural site in the valley showed a late-year increase in activity during October and November, possibly indicative of migratory activity. |