Clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of South Africa
Knowledge of cetacean occurrence and behaviour in southern African waters is limited, and passive acoustic monitoring has the potential to address this gap efficiently. Seasonal acoustic occurrence and diel-vocalizing patterns of sperm whales in relation to environmental conditions are described her...
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Online Access: | https://doi.org/10.3354/esr01089 https://doaj.org/article/1c43ec6826d941d2b88394a95f70be7b |
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ftdoajarticles:oai:doaj.org/article:1c43ec6826d941d2b88394a95f70be7b 2023-05-15T18:26:32+02:00 Clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of South Africa Shabangu, FW Andrew, RK 2020-12-01T00:00:00Z https://doi.org/10.3354/esr01089 https://doaj.org/article/1c43ec6826d941d2b88394a95f70be7b EN eng Inter-Research https://www.int-res.com/abstracts/esr/v43/p475-494/ https://doaj.org/toc/1863-5407 https://doaj.org/toc/1613-4796 1863-5407 1613-4796 doi:10.3354/esr01089 https://doaj.org/article/1c43ec6826d941d2b88394a95f70be7b Endangered Species Research, Vol 43, Pp 475-494 (2020) Zoology QL1-991 Botany QK1-989 article 2020 ftdoajarticles https://doi.org/10.3354/esr01089 2022-12-31T10:46:13Z Knowledge of cetacean occurrence and behaviour in southern African waters is limited, and passive acoustic monitoring has the potential to address this gap efficiently. Seasonal acoustic occurrence and diel-vocalizing patterns of sperm whales in relation to environmental conditions are described here using passive acoustic monitoring data collected off the west coast of South Africa. Four autonomous acoustic recorders (AARs) were deployed on 3 oceanographic moorings from July 2014 to January 2017. Sperm whale clicks were detected year round in most recording sites, with peaks in acoustic occurrence in summer and late winter through spring. Diel-vocalizing patterns were detected in winter, spring and summer. Higher percentages of sperm whale clicks were recorded by AARs deployed at 1100 m water depth compared to those concurrently deployed at 850 and 4500 m, likely inferring that the whales exhibited some preference to water depths around 1100 m. Acoustic propagation modelling suggested a maximum detection range of 83 km in winter for sperm whale clicks produced at 1100 m. Random forest models classified daylight regime, sea surface height anomaly and month of the year as the most important predictors of sperm whale acoustic occurrence. The continuous acoustic occurrence of sperm whales suggests that the study area supports large biomasses of prey to sustain this species’ food requirements year round. This is the first study to describe the seasonal acoustic occurrence and diel-vocalizing patterns of sperm whales off the west coast of South Africa, extending knowledge of the species previously available only through whaling records. Article in Journal/Newspaper Sperm whale Directory of Open Access Journals: DOAJ Articles Endangered Species Research 43 475 494 |
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Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Zoology QL1-991 Botany QK1-989 |
spellingShingle |
Zoology QL1-991 Botany QK1-989 Shabangu, FW Andrew, RK Clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of South Africa |
topic_facet |
Zoology QL1-991 Botany QK1-989 |
description |
Knowledge of cetacean occurrence and behaviour in southern African waters is limited, and passive acoustic monitoring has the potential to address this gap efficiently. Seasonal acoustic occurrence and diel-vocalizing patterns of sperm whales in relation to environmental conditions are described here using passive acoustic monitoring data collected off the west coast of South Africa. Four autonomous acoustic recorders (AARs) were deployed on 3 oceanographic moorings from July 2014 to January 2017. Sperm whale clicks were detected year round in most recording sites, with peaks in acoustic occurrence in summer and late winter through spring. Diel-vocalizing patterns were detected in winter, spring and summer. Higher percentages of sperm whale clicks were recorded by AARs deployed at 1100 m water depth compared to those concurrently deployed at 850 and 4500 m, likely inferring that the whales exhibited some preference to water depths around 1100 m. Acoustic propagation modelling suggested a maximum detection range of 83 km in winter for sperm whale clicks produced at 1100 m. Random forest models classified daylight regime, sea surface height anomaly and month of the year as the most important predictors of sperm whale acoustic occurrence. The continuous acoustic occurrence of sperm whales suggests that the study area supports large biomasses of prey to sustain this species’ food requirements year round. This is the first study to describe the seasonal acoustic occurrence and diel-vocalizing patterns of sperm whales off the west coast of South Africa, extending knowledge of the species previously available only through whaling records. |
format |
Article in Journal/Newspaper |
author |
Shabangu, FW Andrew, RK |
author_facet |
Shabangu, FW Andrew, RK |
author_sort |
Shabangu, FW |
title |
Clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of South Africa |
title_short |
Clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of South Africa |
title_full |
Clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of South Africa |
title_fullStr |
Clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of South Africa |
title_full_unstemmed |
Clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of South Africa |
title_sort |
clicking throughout the year: sperm whale clicks in relation to environmental conditions off the west coast of south africa |
publisher |
Inter-Research |
publishDate |
2020 |
url |
https://doi.org/10.3354/esr01089 https://doaj.org/article/1c43ec6826d941d2b88394a95f70be7b |
genre |
Sperm whale |
genre_facet |
Sperm whale |
op_source |
Endangered Species Research, Vol 43, Pp 475-494 (2020) |
op_relation |
https://www.int-res.com/abstracts/esr/v43/p475-494/ https://doaj.org/toc/1863-5407 https://doaj.org/toc/1613-4796 1863-5407 1613-4796 doi:10.3354/esr01089 https://doaj.org/article/1c43ec6826d941d2b88394a95f70be7b |
op_doi |
https://doi.org/10.3354/esr01089 |
container_title |
Endangered Species Research |
container_volume |
43 |
container_start_page |
475 |
op_container_end_page |
494 |
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1766208493128253440 |