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characters. Chaerephon sp. nov. occurs at three sites in the drier western portion of the island. We also provide some natural history and distributional information on other Malagasy members of this family.

northern Madagascar. We measured bat behavior, including time activity budgets, under two levels of experimental human visit proximity (far and near) and illumination (low and high). These visits caused an increase in bat flights and an increase in alertness in a frequently-visited colony with faint ambient daylight. The greatest response occurred for human approaches to 5–6 m that directly illuminated the bats and the least response occurred for approaches to 12–14 m that did not directly illuminate the bats. In an infrequently-visited colony with no ambient daylight, visits that remained 12–14 m away and did not illuminate the bats directly caused an increase in alert behavior and a decrease in bat grooming behavior. The difference in response between the colonies suggests that R. madagascariensis may demonstrate an attenuated response to some frequent human visits. Alternatively, colonies roosting with some ambient light may be less sensitive to disturbance from visits, and colonies with previous experience primarily with hunting visits may be more responsive to disturbance. Maintaining a minimum visit distance of 12 m and not illuminating the bats directly, as well as not opening other roost sites to tourism, is likely to help to limit disturbance of R. madagascariensis by tourists at Ankarana.

Time-expanded recordings of calls from 153 bats from 15 species were analyzed using five commonly used temporal and frequency variables measured from spectrographs. Echolocation calls for six species (Scotophilus tandrefana, S. marovaza, Emballonura tiavato, Neoromicia spp., N. malagasyensis and Triaenops auritus) are described for the first time. A discriminant function analysis revealed that a function based on the five measured variables provided a correct overall classification of 82.2%. Three groups of echolocation calls based upon the temporal and frequency characteristics of calls are recognized. The Constant Frequency group consists of hipposiderids and Emballonura spp., the Frequency Modulated/Quasi-Constant Frequency group is dominated by vespertilionids, and one species, Myotis goudoti, is in the Frequency Modulated group. Further we describe the utility of using acoustic sampling in inventory and monitoring studies, and in investigations of habitat use.