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Occupancy analysis and its ability to account for differential detection probabilities is important for studies in which detecting echolocation calls is used as a measure of bat occurrence and activity. We examined the feasibility of remotely acquiring bat encounter histories to estimate detection probability and occupancy. We used echolocation detectors coupled to digital recorders operating at a series of proximate sites on consecutive nights in 2 trial surveys for the Hawaiian hoary bat (Lasiurus cinereus semotus). Our results confirmed that the technique is readily amenable for use in occupancy analysis. We also conducted a simulation exercise to assess the effects of sampling effort on parameter estimation. The results indicated that the precision and bias of parameter estimation were often more influenced by the number of sites sampled than number of visits. Acceptable accuracy often was not attained until at least 15 sites or 15 visits were used to estimate detection probability and occupancy. The method has significant potential for use in monitoring trends in bat activity and in comparative studies of habitat use. Key words: acoustic detection, Anabat, bat, detection probability, echolocation, occupancy, sampling design

A study was conducted to determine the day-roost selection of evening bats (Nycticeius humeralis) at multiple scales in mature longleaf (Pinus palustirs; natural) and intensely managed loblolly pine (P.taeda; managed) landscapes in the Gulf Coastal Plain of Georgia, USA. It was found that the evening bats in the natural habitats with more number of rooting structures, selected day-roosts with favorable landscape features like nearness to water and foraging sites and benefits like less traveling costs while the bats on the managed sites chose day-roosts only at the tree and plot scale.