Elucidating the diel and seasonal calling behaviour of Elachistocleis matogrosso (Anura: Microhylidae)

ABSTRACT

Acoustic monitoring provides the opportunity to study ecological processes that are difficult to assess with traditional surveys. Elachistocleis matogrosso is an anuran species, described in 2010, for which limited biological information is available. This study investigated the calling activity of the species in the north-eastern portion of the Pantanal, Brazil, a wetland area with marked seasonality between the dry and wet seasons. The calling activity of E. matogrosso was monitored using automated digital recorders in combination with automated signal recognition software over two different annual cycles. The species was vocally active only during the wet season (October – April), with a peak in November-December during the 2013–2014 annual cycle and in February-March during the 2015–2016 annual cycle. The peak calling activity occurred at dusk. This species has nocturnal habits and an explosive breeding activity. The detection of the species was intermittent, which suggests that environmental predictors or site-specific conditions might play an important role in species detection. Moreover, this intermittent occupancy indicated that surveys that employ traditional field techniques would likely fail to detect this species. We describe an effective protocol for detecting E. matogrosso with acoustic monitoring, which requires recording during 20 days in February from 17:01 to 05:00. Our procedure would be easy to adapt to other anuran species, and it could be used for investigating new localities and assessing population changes over time.

KEYWORDS:

• Anurans
• acoustic monitoring
• automated recorder
• calling activity
• Microhylidae
• Pantanal
• monitoring protocol

Acknowledgements

We thank the SESC Pantanal, Mato Grosso, for permission to conduct research on their property and for their logistical help with our fieldwork. This study is part of the biodiversity monitoring project: Sounds of the Pantanal – The Pantanal Automated Acoustic Biodiversity Monitoring of INAU, Cuiabá, Mato Grosso, Brazil, conducted under SISBIO permit no. 39095 (KLS).

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability

Data supporting the results and analyses presented in the paper can be found at: https://doi.10.6084/m9.figshare.8246123.v1

Supplementary material

Supplementary material data for this article can be accessed here.

Additional information

Funding

We greatly appreciate the financial support of the following institutions: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brasil [CAPES – INCT/MCTI/CNPq/CAPES/FAPs no.16/2014]; Instituto Nacional de Ciência e Tecnologia em Áreas Úmidas [INAU/UFMT/CNPq]; Centro de Pesquisa do Pantanal (CPP); Brehm Foundation for International Bird Conservation (BF), Bonn, Germany; Conselho Nacional de Desenvolvimento Científico e Tecnológico for a research fellowship to CS [CNPq no. 3123038/2018-1].