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Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

Combining acoustic localisation and high-resolution land cover classification to study predator vocalisation behaviour

Elisabeth Bru https://orcid.org/0000-0003-3451-1450 A B * , Bethany R. Smith https://orcid.org/0000-0002-7435-9265 C D , Hannah Butkiewicz E , Amy C. Fontaine F , Angela Dassow https://orcid.org/0000-0001-9513-2484 G , Jessica L. Owens H , Holly Root-Gutteridge https://orcid.org/0000-0001-9854-2948 I , Loretta Schindler J and Arik Kershenbaum https://orcid.org/0000-0003-0464-0243 K
+ Author Affiliations
- Author Affiliations

A Department of Zoology, University of Cambridge, Cambridge CB3 0JG, UK.

B Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot SL5 7PY, UK.

C School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Brackenhurst Lane, Southwell NG25 0QF, UK.

D Mammal Society, Milton Abbas, Dorset DT11 0BL, UK.

E College of Natural Resources, University of Wisconsin-Stevens Point, 2100 Main Street, Stevens Point, WI 54481, USA.

F Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA.

G Biology Department, Carthage College, 2001 Alford Park Drive, Kenosha, WI 53140, USA.

H Unleashed Training, LLC, Daytona Beach, FL 32114, USA.

I School of Life Sciences, University of Lincoln, Beevor Street, Lincoln, LN6 7DL, UK.

J Department of Zoology, Faculty of Science, Charles University, Prague 128 44, Czech Republic.

K Girton College, and Department of Zoology, University of Cambridge, Cambridge CB3 0JG, UK.

* Correspondence to: lizzie.bru44@gmail.com

Handling Editor: Stuart Parsons

Wildlife Research 50(12) 965-979 https://doi.org/10.1071/WR22007
Submitted: 18 January 2022  Accepted: 22 December 2022   Published: 13 February 2023

© 2023 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Context: The ecology of cryptic animals is difficult to study without invasive tagging approaches or labour-intensive field surveys. Acoustic localisation provides an effective way to locate vocalising animals using acoustic recorders. Combining this with land cover classification gives new insight into wild animal behaviour using non-invasive tools.

Aims: This study aims to demonstrate how acoustic localisation – combined with high-resolution land cover classification – permits the study of the ecology of vocalising animals in the wild. We illustrate this technique by investigating the effect of land cover and distances to anthropogenic features on coyote and wolf vocal behaviour.

Methods: We collected recordings over 13 days in Wisconsin, USA, and triangulated vocalising animals’ locations using acoustic localisation. We then mapped these locations onto land cover using a high-resolution land cover map we produced for the area.

Key results: Neither coyotes nor wolves vocalised more in one habitat type over another. Coyotes vocalised significantly closer to all human features than expected by chance, whereas wolves vocalised significantly further away. When vocalising closer to human features, coyotes selected forests but wolves showed no habitat preference.

Conclusions: This novel combination of two sophisticated, autonomous sensing-driven tools permits us to examine animal land use and behavioural ecology using passive sensors, with the aim of drawing ecologically important conclusions.

Implications: We envisage that this method can be used at larger scales to aid monitoring of vocally active animals across landscapes. Firstly, it permits us to characterise habitat use while vocalising, which is an essential behaviour for many species. Furthermore, if combined with additional knowledge of how a species’ habitat selection while vocalising relates to its general habitat use, this method could permit the derivation of future conclusions on prevailing landscape use. In summary, this study demonstrates the potential of integrating acoustic localisation with land cover classification in ecological research.

Keywords: anthropogenic disturbance, bioacoustics, Canis latrans, Canis lupus, habitat selection, howl, multilateration, passive acoustic monitoring, remote sensing.


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