Abstract
Nocturnal activity patterns of New Zealand lesser short‐tailed bats (Mystacina tuberculata) were examined in temperate beech (Nothofagus) rainforest in the Eglinton Valley, Fiordland, during early autumn in 1997 and summer‐autumn 1997–98. Miniature radio‐transmitters were attached to 23 bats, 12 of which were followed for between 1 and 3 whole nights. They emerged from roosts an average of 42.0 ± 8.0 (SD) min after sunset, and remained active for an average of 456.9 ± 45.6 min (90–100% of the time spent away from their day roost). They foraged throughout the night, spending only 16.1 ± 7.8 min inactive per night. Bats travelled large distances in a night and were capable of flying at speeds up to 44.3 km/h (12.3 ms–1). However, most flight speeds were relatively slow (mean flight speed = 2.5 km/h (0.7 ms–1) between fixes). This, coupled with the high frequency of short distances travelled between estimated locations, indicated that bats concentrated their activity in one or several relatively small areas dispersed widely in the valley.