Cargando…

Low-frequency sampling rates are effective to record bottlenose dolphins

Acoustic monitoring in cetacean studies is an effective but expensive approach. This is partly because of the high sampling rate required by acoustic devices when recording high-frequency echolocation clicks. However, the proportion of echolocation clicks recorded at different frequencies is unknown...

Descripción completa

Detalles Bibliográficos
Autores principales: Romeu, Bianca, Machado, Alexandre M. S., Daura-Jorge, Fábio G., Cremer, Marta J., de Moraes Alves, Ana Kássia, Simões-Lopes, Paulo C.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8316790/
https://www.ncbi.nlm.nih.gov/pubmed/34350008
http://dx.doi.org/10.1098/rsos.201598
_version_ 1783729937108172800
author Romeu, Bianca
Machado, Alexandre M. S.
Daura-Jorge, Fábio G.
Cremer, Marta J.
de Moraes Alves, Ana Kássia
Simões-Lopes, Paulo C.
author_facet Romeu, Bianca
Machado, Alexandre M. S.
Daura-Jorge, Fábio G.
Cremer, Marta J.
de Moraes Alves, Ana Kássia
Simões-Lopes, Paulo C.
author_sort Romeu, Bianca
collection PubMed
description Acoustic monitoring in cetacean studies is an effective but expensive approach. This is partly because of the high sampling rate required by acoustic devices when recording high-frequency echolocation clicks. However, the proportion of echolocation clicks recorded at different frequencies is unknown for many species, including bottlenose dolphins. Here, we investigated the echolocation clicks of two subspecies of bottlenose dolphins in the western South Atlantic Ocean. The possibility of recording echolocation clicks at 24 and 48 kHz was assessed by two approaches. First, we considered the clicks in the frequency range up to 96 kHz. We found a loss of 0.95–13.90% of echolocation clicks in the frequency range below 24 kHz, and 0.01–0.42% below 48 kHz, to each subspecies. Then, we evaluated these recordings downsampled at 48 and 96 kHz and confirmed that echolocation clicks are recorded at these lower frequencies, with some loss. Therefore, despite reaching high frequencies, the clicks can also be recorded at lower frequencies because echolocation clicks from bottlenose dolphins are broadband. We concluded that ecological studies based on the presence–absence data are still effective for bottlenose dolphins when acoustic devices with a limited sampling rate are used.
format Online
Article
Text
id pubmed-8316790
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher The Royal Society
record_format MEDLINE/PubMed
spelling pubmed-83167902021-08-03 Low-frequency sampling rates are effective to record bottlenose dolphins Romeu, Bianca Machado, Alexandre M. S. Daura-Jorge, Fábio G. Cremer, Marta J. de Moraes Alves, Ana Kássia Simões-Lopes, Paulo C. R Soc Open Sci Ecology, Conservation and Global Change Biology Acoustic monitoring in cetacean studies is an effective but expensive approach. This is partly because of the high sampling rate required by acoustic devices when recording high-frequency echolocation clicks. However, the proportion of echolocation clicks recorded at different frequencies is unknown for many species, including bottlenose dolphins. Here, we investigated the echolocation clicks of two subspecies of bottlenose dolphins in the western South Atlantic Ocean. The possibility of recording echolocation clicks at 24 and 48 kHz was assessed by two approaches. First, we considered the clicks in the frequency range up to 96 kHz. We found a loss of 0.95–13.90% of echolocation clicks in the frequency range below 24 kHz, and 0.01–0.42% below 48 kHz, to each subspecies. Then, we evaluated these recordings downsampled at 48 and 96 kHz and confirmed that echolocation clicks are recorded at these lower frequencies, with some loss. Therefore, despite reaching high frequencies, the clicks can also be recorded at lower frequencies because echolocation clicks from bottlenose dolphins are broadband. We concluded that ecological studies based on the presence–absence data are still effective for bottlenose dolphins when acoustic devices with a limited sampling rate are used. The Royal Society 2021-07-28 /pmc/articles/PMC8316790/ /pubmed/34350008 http://dx.doi.org/10.1098/rsos.201598 Text en © 2021 The Authors. https://creativecommons.org/licenses/by/4.0/Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, provided the original author and source are credited.
spellingShingle Ecology, Conservation and Global Change Biology
Romeu, Bianca
Machado, Alexandre M. S.
Daura-Jorge, Fábio G.
Cremer, Marta J.
de Moraes Alves, Ana Kássia
Simões-Lopes, Paulo C.
Low-frequency sampling rates are effective to record bottlenose dolphins
title Low-frequency sampling rates are effective to record bottlenose dolphins
title_full Low-frequency sampling rates are effective to record bottlenose dolphins
title_fullStr Low-frequency sampling rates are effective to record bottlenose dolphins
title_full_unstemmed Low-frequency sampling rates are effective to record bottlenose dolphins
title_short Low-frequency sampling rates are effective to record bottlenose dolphins
title_sort low-frequency sampling rates are effective to record bottlenose dolphins
topic Ecology, Conservation and Global Change Biology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8316790/
https://www.ncbi.nlm.nih.gov/pubmed/34350008
http://dx.doi.org/10.1098/rsos.201598
work_keys_str_mv AT romeubianca lowfrequencysamplingratesareeffectivetorecordbottlenosedolphins
AT machadoalexandrems lowfrequencysamplingratesareeffectivetorecordbottlenosedolphins
AT daurajorgefabiog lowfrequencysamplingratesareeffectivetorecordbottlenosedolphins
AT cremermartaj lowfrequencysamplingratesareeffectivetorecordbottlenosedolphins
AT demoraesalvesanakassia lowfrequencysamplingratesareeffectivetorecordbottlenosedolphins
AT simoeslopespauloc lowfrequencysamplingratesareeffectivetorecordbottlenosedolphins