Acoustic identification of two morphologically similar bat species, Miniopterus magnater and Miniopterus fuliginosus (Chiroptera, Miniopteridae)

Abstract

Abstract Bats play important roles in ecosystems, and are thus considered bioindicators. Libraries of echolocation calls provide huge potential resources for bat species identifications, ecological studies and conservation surveys. Here, the echolocation calls of two morphologically similar bat species (Miniopterus magnater and Miniopterus fuliginosus) were recorded and described in order to characterize vocal signatures for field identification in China. Both M. magnater and M. fuliginosus emitted short frequency modulated echolocation calls with narrow bandwidths. Each call of the former species included two harmonics, with the first harmonic being the strongest, whereas calls of the latter species normally contained one harmonic. Although call durations were similar between the two species, there were significant differences in start, end and peak frequencies between M. magnater and M. fuliginous. The results showed that 92.3% of all calls recorded in China were attributed to the correct species based on spectral features of echolocation calls. We concluded that echolocation calls are valuable characters for the identification of morphologically similar bat species.