Acoustic monitoring of rock ptarmigan: A multi-year comparison with point-count protocol

• Published in: Ecological Indicators
• Main Authors: Marin-Cudraz, Thibaut, Muffat-Joly, Bertrand, Novoa, Claude, Aubry, Philippe, Desmet, Jean-François, Mahamoud-Issa, Mathieu, Nicolè, Florence, van Niekerk, Mark, Mathevon, Nicolas, Sèbe, Frédéric
• Other Authors: Institut des Neurosciences Paris-Saclay (NeuroPSI), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Office National de la Chasse et de la Faune Sauvage, Direction des Etudes et de la Recherche, Groupe Recherche & Information sur la Faune & Ecosystème Montagne, Adam Mickiewicz University in Poznań (UAM), Laboratoire de Biotechnologies Végétales appliquées aux Plantes Aromatiques et Médicinales (BVPAM), Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Acoustic monitoring; Rock ptarmigan; Point-count protocol; Long-term study; Individual information; Methodology comparison; [SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology; [SDV.NEU.PC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Psychology and behavior; [SDV.NEU.SC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Cognitive Sciences; rock ptarmigan
• Online Access: https://hal.science/hal-02195956; https://hal.science/hal-02195956/document; https://hal.science/hal-02195956/file/S1470160X19300895.pdf; https://doi.org/10.1016/j.ecolind.2019.01.071

International audience The cost-effectiveness and reduced human effort employed in setting up acoustic monitoring in the field makes bioacoustics an appealing option for wildlife monitoring. This is especially true for secretive vocal species living in remote places. However, acoustic monitoring still raises questions regarding its reliability when compared to other, human-driven methods. In this study we compare different approaches to count rock ptarmigan males, an alpine bird species which lives at high altitudes. The monitoring of rock ptarmigan populations is traditionally conducted using a point-count protocol, with human observers counting singing males from a set of different points. We assessed the (1) feasibility and (2) reliability of an alternative counting method based on acoustic recordings followed by signal analysis and a dedicated statistical approach to estimate the abundance of males. We then (3) compared the results obtained with this bioacoustics monitoring method with those obtained through the point-count protocol approach over three consecutive years. Acoustic analysis demonstrated that rock ptarmigan vocalizations exhibit an individual stereotypy that can be used to estimate the abundance of males. Simulations, using subsets of our recording dataset, demonstrated that the clustering methods used to discriminate between males based on their vocalizations are sensitive to both the number of recorded signals, as well as the number of individuals to be discriminated. Despite these limitations, we highlight the reliability of the bioacoustics approach, showing that it avoids both observer bias and double counting, contrary to the pointcount protocol where this may occur and impair the data reliability. Overall, our study suggests that bioacoustics monitoring should be used in addition to traditional counting methods to obtain a more accurate estimate of rock ptarmigan abundance within Alpine environments.