Modeling Distribution and Abundance of Antarctic Baleen Whales Using Ships of Opportunity
Information on animal abundance and distribution is at the cornerstone of many wildlife and conservation strategies. However, these data can be difficult and costly to obtain for cetacean species. The expense of sufficient ship time to conduct design-unbiased line transect surveys may be simply out...
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ftdoajarticles:oai:doaj.org/article:89816518932343e29949972ae2cc960c 2023-05-15T13:32:25+02:00 Modeling Distribution and Abundance of Antarctic Baleen Whales Using Ships of Opportunity Rob Williams Sharon L. Hedley Philip S. Hammond 2006-06-01T00:00:00Z https://doi.org/10.5751/ES-01534-110101 https://doaj.org/article/89816518932343e29949972ae2cc960c EN eng Resilience Alliance http://www.ecologyandsociety.org/vol11/iss1/art1/ https://doaj.org/toc/1708-3087 1708-3087 doi:10.5751/ES-01534-110101 https://doaj.org/article/89816518932343e29949972ae2cc960c Ecology and Society, Vol 11, Iss 1, p 1 (2006) abundance Antarctic baleen whale cetacean distance sampling distribution line transect platform of opportunity spatial model Biology (General) QH301-705.5 Ecology QH540-549.5 article 2006 ftdoajarticles https://doi.org/10.5751/ES-01534-110101 2022-12-31T13:13:42Z Information on animal abundance and distribution is at the cornerstone of many wildlife and conservation strategies. However, these data can be difficult and costly to obtain for cetacean species. The expense of sufficient ship time to conduct design-unbiased line transect surveys may be simply out of reach for researchers in many countries, which nonetheless grapple with problems of conservation of endangered species, by-catch of small cetaceans in commercial fisheries, and progression toward ecosystem-based fisheries management. Recently developed spatial modeling techniques show promise for estimating wildlife abundance using non-randomized surveys, but have yet to receive much field-testing in areas where designed surveys have also been conducted. Effort and sightings data were collected along 9 650 km of transects aboard ships of opportunity in the Southern Ocean during the austral summers of 2000-2001 and 2001-2002. Generalized additive models with generalized cross-validation were used to express heterogeneity of cetacean sightings as functions of spatial covariates. Models were used to map predicted densities and to estimate abundance of humpback, minke, and fin whales in the Drake Passage and along the Antarctic Peninsula. All species' distribution maps showed strong density gradients, which were robust to jackknife resampling when each of 14 trips was removed sequentially with replacement. Looped animations of model predictions of whale density illustrate uncertainty in distribution estimates in a way that is informative to non-scientists. The best abundance estimate for humpback whales was 1 829 (95% CI: 978-3 422). Abundance of fin whales was 4 487 (95% CI: 1 326-15 179) and minke whales was 1,544 (95% CI: 1,221-1,953). These estimates agreed roughly with those reported from a designed survey conducted in the region during the previous austral summer. These estimates assumed that all animals on the trackline were detected, but preliminary results suggest that any negative bias due to violation of ... Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula baleen whale baleen whales Drake Passage Southern Ocean Directory of Open Access Journals: DOAJ Articles Antarctic Southern Ocean The Antarctic Antarctic Peninsula Austral Drake Passage Ecology and Society 11 1 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
abundance Antarctic baleen whale cetacean distance sampling distribution line transect platform of opportunity spatial model Biology (General) QH301-705.5 Ecology QH540-549.5 |
spellingShingle |
abundance Antarctic baleen whale cetacean distance sampling distribution line transect platform of opportunity spatial model Biology (General) QH301-705.5 Ecology QH540-549.5 Rob Williams Sharon L. Hedley Philip S. Hammond Modeling Distribution and Abundance of Antarctic Baleen Whales Using Ships of Opportunity |
topic_facet |
abundance Antarctic baleen whale cetacean distance sampling distribution line transect platform of opportunity spatial model Biology (General) QH301-705.5 Ecology QH540-549.5 |
description |
Information on animal abundance and distribution is at the cornerstone of many wildlife and conservation strategies. However, these data can be difficult and costly to obtain for cetacean species. The expense of sufficient ship time to conduct design-unbiased line transect surveys may be simply out of reach for researchers in many countries, which nonetheless grapple with problems of conservation of endangered species, by-catch of small cetaceans in commercial fisheries, and progression toward ecosystem-based fisheries management. Recently developed spatial modeling techniques show promise for estimating wildlife abundance using non-randomized surveys, but have yet to receive much field-testing in areas where designed surveys have also been conducted. Effort and sightings data were collected along 9 650 km of transects aboard ships of opportunity in the Southern Ocean during the austral summers of 2000-2001 and 2001-2002. Generalized additive models with generalized cross-validation were used to express heterogeneity of cetacean sightings as functions of spatial covariates. Models were used to map predicted densities and to estimate abundance of humpback, minke, and fin whales in the Drake Passage and along the Antarctic Peninsula. All species' distribution maps showed strong density gradients, which were robust to jackknife resampling when each of 14 trips was removed sequentially with replacement. Looped animations of model predictions of whale density illustrate uncertainty in distribution estimates in a way that is informative to non-scientists. The best abundance estimate for humpback whales was 1 829 (95% CI: 978-3 422). Abundance of fin whales was 4 487 (95% CI: 1 326-15 179) and minke whales was 1,544 (95% CI: 1,221-1,953). These estimates agreed roughly with those reported from a designed survey conducted in the region during the previous austral summer. These estimates assumed that all animals on the trackline were detected, but preliminary results suggest that any negative bias due to violation of ... |
format |
Article in Journal/Newspaper |
author |
Rob Williams Sharon L. Hedley Philip S. Hammond |
author_facet |
Rob Williams Sharon L. Hedley Philip S. Hammond |
author_sort |
Rob Williams |
title |
Modeling Distribution and Abundance of Antarctic Baleen Whales Using Ships of Opportunity |
title_short |
Modeling Distribution and Abundance of Antarctic Baleen Whales Using Ships of Opportunity |
title_full |
Modeling Distribution and Abundance of Antarctic Baleen Whales Using Ships of Opportunity |
title_fullStr |
Modeling Distribution and Abundance of Antarctic Baleen Whales Using Ships of Opportunity |
title_full_unstemmed |
Modeling Distribution and Abundance of Antarctic Baleen Whales Using Ships of Opportunity |
title_sort |
modeling distribution and abundance of antarctic baleen whales using ships of opportunity |
publisher |
Resilience Alliance |
publishDate |
2006 |
url |
https://doi.org/10.5751/ES-01534-110101 https://doaj.org/article/89816518932343e29949972ae2cc960c |
geographic |
Antarctic Southern Ocean The Antarctic Antarctic Peninsula Austral Drake Passage |
geographic_facet |
Antarctic Southern Ocean The Antarctic Antarctic Peninsula Austral Drake Passage |
genre |
Antarc* Antarctic Antarctic Peninsula baleen whale baleen whales Drake Passage Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Peninsula baleen whale baleen whales Drake Passage Southern Ocean |
op_source |
Ecology and Society, Vol 11, Iss 1, p 1 (2006) |
op_relation |
http://www.ecologyandsociety.org/vol11/iss1/art1/ https://doaj.org/toc/1708-3087 1708-3087 doi:10.5751/ES-01534-110101 https://doaj.org/article/89816518932343e29949972ae2cc960c |
op_doi |
https://doi.org/10.5751/ES-01534-110101 |
container_title |
Ecology and Society |
container_volume |
11 |
container_issue |
1 |
_version_ |
1766026910731599872 |