First characterization of the echolocation calls of Myotis dinellii (Chiroptera: Vespertilionidae)

Abstract

The yellowish myotis (Myotis dinellii) is an arthropodophagous bat with a distribution restricted to Bolivia and Argentina. In this study, the search call of Myotis dinellii is characterized for the first time. Twenty-one specimens of M. dinellii were collected from three natural areas in the Yungas Forests in Tucuman Province (Argentina). The specimens were recorded using the hand release technique with an Echo Meter Touch device. A total of 27 passes and 121 pulses were analyzed considering the following parameters: pulse duration, initial and final frequency, bandwidth, peak frequency, minimum and maximum frequency, and interval between pulses. The calls show a single harmonic with downward modulated frequency followed by a downward quasi-constant frequency. On average, the calls were emitted between 78.8 and 39.6 kHz with a duration of 3.5 ms. The recordings and analysis of acoustic parameters provide the basis for future research of this and other bat species in Argentina. These results contribute to the design of the first bat sound library in Argentina.