Echolocation calls of fourteen bats from eastern New South Wales.

Abstract

The echolocation calls of fourteen species of insectivorous bats were recorded and analysed to obtain a suit of call descriptors for use in field identification of bats. Measurements relating to frequency and duration of the calls can be used to discriminate species only when a large number of calls are sampled and when mean values for each measurements and species are used. Some overlap between calls of certain species leads to considerable ambiguity in identification. Clarification is possible, however, when both the pattern of frequency change over time for each call and the pattern of pulses in each call sequence are also considered. All FM-bats are similar in that the bandwidth of their calls typically spans one octave. Similarities in a whole suite of call characteristics occur among bats of different taxonomic groups and are more likely to represent ecological relationships among species than phylogenetic ones.