Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds.
The western South Atlantic (WSA) humpback whale population inhabits the coast of Brazil during the breeding and calving season in winter and spring. This population was depleted to near extinction by whaling in the mid-twentieth century. Despite recent signs of recovery, increasing coastal and offsh...
Published in: | PLOS ONE |
---|---|
Main Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Public Library of Science (PLoS)
2016
|
Subjects: | |
Online Access: | https://doi.org/10.1371/journal.pone.0164596 https://doaj.org/article/d3046862523f4c67854add38799bf598 |
id |
ftdoajarticles:oai:doaj.org/article:d3046862523f4c67854add38799bf598 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:d3046862523f4c67854add38799bf598 2023-05-15T16:35:51+02:00 Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds. Guilherme A Bortolotto Daniel Danilewicz Artur Andriolo Eduardo R Secchi Alexandre N Zerbini 2016-01-01T00:00:00Z https://doi.org/10.1371/journal.pone.0164596 https://doaj.org/article/d3046862523f4c67854add38799bf598 EN eng Public Library of Science (PLoS) http://europepmc.org/articles/PMC5063365?pdf=render https://doaj.org/toc/1932-6203 1932-6203 doi:10.1371/journal.pone.0164596 https://doaj.org/article/d3046862523f4c67854add38799bf598 PLoS ONE, Vol 11, Iss 10, p e0164596 (2016) Medicine R Science Q article 2016 ftdoajarticles https://doi.org/10.1371/journal.pone.0164596 2022-12-31T12:15:08Z The western South Atlantic (WSA) humpback whale population inhabits the coast of Brazil during the breeding and calving season in winter and spring. This population was depleted to near extinction by whaling in the mid-twentieth century. Despite recent signs of recovery, increasing coastal and offshore development pose potential threats to these animals. Therefore, continuous monitoring is needed to assess population status and support conservation strategies. The aim of this work was to present ship-based line-transect estimates of abundance for humpback whales in their WSA breeding ground and to investigate potential changes in population size. Two cruises surveyed the coast of Brazil during August-September in 2008 and 2012. The area surveyed in 2008 corresponded to the currently recognized population breeding area; effort in 2012 was limited due to unfavorable weather conditions. WSA humpback whale population size in 2008 was estimated at 16,410 (CV = 0.228, 95% CI = 10,563-25,495) animals. In order to compare abundance between 2008 and 2012, estimates for the area between Salvador and Cabo Frio, which were consistently covered in the two years, were computed at 15,332 (CV = 0.243, 95% CI = 9,595-24,500) and 19,429 (CV = 0.101, 95% CI = 15,958-23,654) whales, respectively. The difference in the two estimates represents an increase of 26.7% in whale numbers in a 4-year period. The estimated abundance for 2008 is considered the most robust for the WSA humpback whale population because the ship survey conducted in that year minimized bias from various sources. Results presented here indicate that in 2008, the WSA humpback whale population was at least around 60% of its estimated pre-modern whaling abundance and that it may recover to its pre-exploitation size sooner than previously estimated. Article in Journal/Newspaper Humpback Whale Megaptera novaeangliae Directory of Open Access Journals: DOAJ Articles PLOS ONE 11 10 e0164596 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Medicine R Science Q |
spellingShingle |
Medicine R Science Q Guilherme A Bortolotto Daniel Danilewicz Artur Andriolo Eduardo R Secchi Alexandre N Zerbini Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds. |
topic_facet |
Medicine R Science Q |
description |
The western South Atlantic (WSA) humpback whale population inhabits the coast of Brazil during the breeding and calving season in winter and spring. This population was depleted to near extinction by whaling in the mid-twentieth century. Despite recent signs of recovery, increasing coastal and offshore development pose potential threats to these animals. Therefore, continuous monitoring is needed to assess population status and support conservation strategies. The aim of this work was to present ship-based line-transect estimates of abundance for humpback whales in their WSA breeding ground and to investigate potential changes in population size. Two cruises surveyed the coast of Brazil during August-September in 2008 and 2012. The area surveyed in 2008 corresponded to the currently recognized population breeding area; effort in 2012 was limited due to unfavorable weather conditions. WSA humpback whale population size in 2008 was estimated at 16,410 (CV = 0.228, 95% CI = 10,563-25,495) animals. In order to compare abundance between 2008 and 2012, estimates for the area between Salvador and Cabo Frio, which were consistently covered in the two years, were computed at 15,332 (CV = 0.243, 95% CI = 9,595-24,500) and 19,429 (CV = 0.101, 95% CI = 15,958-23,654) whales, respectively. The difference in the two estimates represents an increase of 26.7% in whale numbers in a 4-year period. The estimated abundance for 2008 is considered the most robust for the WSA humpback whale population because the ship survey conducted in that year minimized bias from various sources. Results presented here indicate that in 2008, the WSA humpback whale population was at least around 60% of its estimated pre-modern whaling abundance and that it may recover to its pre-exploitation size sooner than previously estimated. |
format |
Article in Journal/Newspaper |
author |
Guilherme A Bortolotto Daniel Danilewicz Artur Andriolo Eduardo R Secchi Alexandre N Zerbini |
author_facet |
Guilherme A Bortolotto Daniel Danilewicz Artur Andriolo Eduardo R Secchi Alexandre N Zerbini |
author_sort |
Guilherme A Bortolotto |
title |
Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds. |
title_short |
Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds. |
title_full |
Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds. |
title_fullStr |
Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds. |
title_full_unstemmed |
Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds. |
title_sort |
whale, whale, everywhere: increasing abundance of western south atlantic humpback whales (megaptera novaeangliae) in their wintering grounds. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2016 |
url |
https://doi.org/10.1371/journal.pone.0164596 https://doaj.org/article/d3046862523f4c67854add38799bf598 |
genre |
Humpback Whale Megaptera novaeangliae |
genre_facet |
Humpback Whale Megaptera novaeangliae |
op_source |
PLoS ONE, Vol 11, Iss 10, p e0164596 (2016) |
op_relation |
http://europepmc.org/articles/PMC5063365?pdf=render https://doaj.org/toc/1932-6203 1932-6203 doi:10.1371/journal.pone.0164596 https://doaj.org/article/d3046862523f4c67854add38799bf598 |
op_doi |
https://doi.org/10.1371/journal.pone.0164596 |
container_title |
PLOS ONE |
container_volume |
11 |
container_issue |
10 |
container_start_page |
e0164596 |
_version_ |
1766026150380830720 |