First estimates of entanglement rate of humpback whales Megaptera novaeangliae observed in coastal Icelandic waters
Entanglement in fishing gear is a significant anthropogenic source of large whale injury and mortality. Although entanglements have been reported in the eastern North Atlantic, their frequency has not been previously estimated. This study used systematic scar analysis to estimate the frequency of no...
Published in: | Endangered Species Research |
---|---|
Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Inter-Research
2019
|
Subjects: | |
Online Access: | https://doi.org/10.3354/esr00936 https://doaj.org/article/8f39a8b35a6f4967b5181ed377d0ed8e |
id |
ftdoajarticles:oai:doaj.org/article:8f39a8b35a6f4967b5181ed377d0ed8e |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:8f39a8b35a6f4967b5181ed377d0ed8e 2023-05-15T16:36:08+02:00 First estimates of entanglement rate of humpback whales Megaptera novaeangliae observed in coastal Icelandic waters Basran, CJ Bertulli, CG Cecchetti, A Rasmussen, MH Whittaker, M Robbins, J 2019-02-01T00:00:00Z https://doi.org/10.3354/esr00936 https://doaj.org/article/8f39a8b35a6f4967b5181ed377d0ed8e EN eng Inter-Research https://www.int-res.com/abstracts/esr/v38/p67-77/ https://doaj.org/toc/1863-5407 https://doaj.org/toc/1613-4796 1863-5407 1613-4796 doi:10.3354/esr00936 https://doaj.org/article/8f39a8b35a6f4967b5181ed377d0ed8e Endangered Species Research, Vol 38, Pp 67-77 (2019) Zoology QL1-991 Botany QK1-989 article 2019 ftdoajarticles https://doi.org/10.3354/esr00936 2022-12-31T01:53:54Z Entanglement in fishing gear is a significant anthropogenic source of large whale injury and mortality. Although entanglements have been reported in the eastern North Atlantic, their frequency has not been previously estimated. This study used systematic scar analysis to estimate the frequency of non-lethal entanglements among individual humpback whales Megaptera novaeangliae off coastal Iceland, from 2005 through 2017. Images of the caudal peduncle and fluke insertions of 379 individuals were analyzed for wrapping injuries and notches known to be indicative of entanglement. The results indicated that at least 24.8% (n = 94, 95% confidence intervals [95% CI]: 20.5-29.1%) of individuals had a history of prior entanglement when first encountered. Depending on the metric used, the whales subsequently acquired new entanglement-related injuries at an average rate of 1.9% (95% CI: 0.6-3.2%) or 16.3% (95% CI: 3.0-29.3%) per year, with no statistically significant change over time. Furthermore, evidence suggests that at least some entanglements occurred locally. Observations of whales with gear still entangling the body confirmed the patterns of injury studied here. These results are lower than scar-based estimates from other parts of the world, but the cause of this difference requires further study. Scar-based methods underestimate the frequency of prior entanglement because some injuries heal beyond recognition, do not involve the caudal peduncle, and may occur on whales that die before they are studied. Long-term monitoring of humpback whale entanglement in Icelandic coastal waters is important for evaluating the local effects of fisheries, as well as the viability of the endangered Cape Verde breeding population. Article in Journal/Newspaper Humpback Whale Iceland Megaptera novaeangliae North Atlantic Directory of Open Access Journals: DOAJ Articles Endangered Species Research 38 67 77 |
institution |
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 Basran, CJ Bertulli, CG Cecchetti, A Rasmussen, MH Whittaker, M Robbins, J First estimates of entanglement rate of humpback whales Megaptera novaeangliae observed in coastal Icelandic waters |
topic_facet |
Zoology QL1-991 Botany QK1-989 |
description |
Entanglement in fishing gear is a significant anthropogenic source of large whale injury and mortality. Although entanglements have been reported in the eastern North Atlantic, their frequency has not been previously estimated. This study used systematic scar analysis to estimate the frequency of non-lethal entanglements among individual humpback whales Megaptera novaeangliae off coastal Iceland, from 2005 through 2017. Images of the caudal peduncle and fluke insertions of 379 individuals were analyzed for wrapping injuries and notches known to be indicative of entanglement. The results indicated that at least 24.8% (n = 94, 95% confidence intervals [95% CI]: 20.5-29.1%) of individuals had a history of prior entanglement when first encountered. Depending on the metric used, the whales subsequently acquired new entanglement-related injuries at an average rate of 1.9% (95% CI: 0.6-3.2%) or 16.3% (95% CI: 3.0-29.3%) per year, with no statistically significant change over time. Furthermore, evidence suggests that at least some entanglements occurred locally. Observations of whales with gear still entangling the body confirmed the patterns of injury studied here. These results are lower than scar-based estimates from other parts of the world, but the cause of this difference requires further study. Scar-based methods underestimate the frequency of prior entanglement because some injuries heal beyond recognition, do not involve the caudal peduncle, and may occur on whales that die before they are studied. Long-term monitoring of humpback whale entanglement in Icelandic coastal waters is important for evaluating the local effects of fisheries, as well as the viability of the endangered Cape Verde breeding population. |
format |
Article in Journal/Newspaper |
author |
Basran, CJ Bertulli, CG Cecchetti, A Rasmussen, MH Whittaker, M Robbins, J |
author_facet |
Basran, CJ Bertulli, CG Cecchetti, A Rasmussen, MH Whittaker, M Robbins, J |
author_sort |
Basran, CJ |
title |
First estimates of entanglement rate of humpback whales Megaptera novaeangliae observed in coastal Icelandic waters |
title_short |
First estimates of entanglement rate of humpback whales Megaptera novaeangliae observed in coastal Icelandic waters |
title_full |
First estimates of entanglement rate of humpback whales Megaptera novaeangliae observed in coastal Icelandic waters |
title_fullStr |
First estimates of entanglement rate of humpback whales Megaptera novaeangliae observed in coastal Icelandic waters |
title_full_unstemmed |
First estimates of entanglement rate of humpback whales Megaptera novaeangliae observed in coastal Icelandic waters |
title_sort |
first estimates of entanglement rate of humpback whales megaptera novaeangliae observed in coastal icelandic waters |
publisher |
Inter-Research |
publishDate |
2019 |
url |
https://doi.org/10.3354/esr00936 https://doaj.org/article/8f39a8b35a6f4967b5181ed377d0ed8e |
genre |
Humpback Whale Iceland Megaptera novaeangliae North Atlantic |
genre_facet |
Humpback Whale Iceland Megaptera novaeangliae North Atlantic |
op_source |
Endangered Species Research, Vol 38, Pp 67-77 (2019) |
op_relation |
https://www.int-res.com/abstracts/esr/v38/p67-77/ https://doaj.org/toc/1863-5407 https://doaj.org/toc/1613-4796 1863-5407 1613-4796 doi:10.3354/esr00936 https://doaj.org/article/8f39a8b35a6f4967b5181ed377d0ed8e |
op_doi |
https://doi.org/10.3354/esr00936 |
container_title |
Endangered Species Research |
container_volume |
38 |
container_start_page |
67 |
op_container_end_page |
77 |
_version_ |
1766026445508837376 |