b) Activity throughout the night
The activity of different Myotis bat species, as measured by acoustic monitoring, varied both through the night, and through the season. Figure 5 shows nightly activity of Natterer’s and Daubenton’s bats - from dusk, for each week of significant activity. There were too few hourly data points for Brandt’s/whiskered and Bechstein’s to analyse in this way. Peak overnight activity for these two species varies slightly between weeks but occurs typically about 4 hours after dusk. Within the swarming period for each individual species there was a tendency for activity to continue further into the night as nights became longer later in the year.