Description of Echolocation Call Parameters for Urban Bats in Vietnam as a Step Towards a More Integrated Acoustic Monitoring of Urban Wildlife in Southeast Asia

Long Kim Pham,Quy Tan Le,Trung Thanh Nguyen,Bang Van Tran,Christian C Voigt

doi:10.3390/d13010018

Abstract

This study is the first step towards more systematic monitoring of urban bat fauna in Vietnam and other Southeast Asian countries by collecting bat echolocation call parameters in Ho Chi Minh and Tra Vinh cities. We captured urban bats and then recorded echolocation calls after releasing in a tent. Additional bat’s echolocation calls from the free-flying bats were recorded at the site where we captured bat. We used the obtained echolocation call parameters for a discriminant function analysis to test the accuracy of classifying these species based on their echolocation call parameters. Data from this pilot work revealed a low level of diversity for the studied bat assemblages. Additionally, the discriminant function analysis successfully classified bats to four bat species with an accuracy of >87.4%. On average, species assignments were correct for all calls from Taphozous melanopogon (100% success rate), for 70% of calls from Pipistrellus javanicus, for 80.8% of calls from Myotis hasseltii and 67.3% of calls from Scotophilus kuhlii. Our study comprises the first quantitative description of echolocation call parameters for urban bats of Vietnam. The success in classifying urban bats based on their echolocation call parameters provides a promising baseline for monitoring the effect of urbanization on bat assemblages in Vietnam and potentially also other Southeast Asian countries.

Highlights

IntroductionVietnam is a country with a large diversity of bat species, counting about 120 species in the last comprehensive review [1]
Accepted: 1 January 2021Vietnam is a country with a large diversity of bat species, counting about 120 species in the last comprehensive review [1]
We confirmed the presence of six bat species for Ho Chi Minh City and Tra Vinh City, belonging to the families Vespertilionidae (4 species), Emballonuridae

Summary

Introduction

Vietnam is a country with a large diversity of bat species, counting about 120 species in the last comprehensive review [1]. Urban areas are expanding at unprecedented rates, exposing wildlife species to novel stressors such as high impervious surfaces, light pollution, and traffic. Some bat species appear to be tolerant towards these stressors, whereas others seem sensitive [10]. This phenomenon turns bats into suitable indicator species and model taxa to study the impact of urbanization on wildlife species [10,11]. Most studies on urban bats have been conducted in so-called developed countries where urbanization is already high (e.g., [12])

Objectives

Methods

Results

Discussion

Conclusion