Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008
Documenting year-round diversity and distribution of marine mammals off Southern California is important for assessment of effects of potentially harmful anthropogenic activities. Although the waters off Southern California have been surveyed extensively for marine mammals over the past 18 years, su...
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ftcdlib:oai:escholarship.org:ark:/13030/qt680173jb 2024-01-07T09:42:20+01:00 Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008 Douglas, Annie B Calambokidis, John Munger, Lisa M Soldevilla, Melissa S Ferguson, Megan C Havron, Andrea M Camacho, Dominique L Campbell, Greg S Hildebrand, John A 198 - 220 2014-01-01 https://escholarship.org/uc/item/680173jb unknown eScholarship, University of California qt680173jb https://escholarship.org/uc/item/680173jb CC-BY Fishery Bulletin, vol 112, iss 2-3 Agricultural Veterinary and Food Sciences Fisheries Sciences Fisheries article 2014 ftcdlib 2023-12-11T19:07:42Z Documenting year-round diversity and distribution of marine mammals off Southern California is important for assessment of effects of potentially harmful anthropogenic activities. Although the waters off Southern California have been surveyed extensively for marine mammals over the past 18 years, such surveys have been periodic and were conducted primarily from summer to fall, thereby missing potential seasonal shifts. We examined seasonal abundance and population density of cetaceans off Southern California from 16 shipboard line-transect surveys conducted quarterly during 2004-08. The study area consisted of 238,494 km2 of coastal, shelf, and pelagic oceanic habitat from nearshore waters to 700 km offshore. Based on 693 encounters of 20 cetacean species, abundance estimates by seasonal period (summer-fall or winter-spring) and depth (shallow: <2000.5 m; deep: ≥2000.5 m) were determined for the 11 most commonly encountered species. The following are values of uncorrected density (individuals/1000 km2, coefficients of variation in parentheses) for the seasonal period and depth with greatest density for a selection of the species in this study: blue whale (Balaenoptera musculus), summer-fall, shallow, 3.2 (0.26); fin whale (B. physalus), summer-fall, shallow, 3.7 (0.30); humpback whale (Megaptera novaeangliae), summer- fall, shallow, 3.1 (0.36); short-beaked common dolphin (Delphinus delphis), summer-fall, shallow, 1319.7 (0.24); long-beaked common dolphin (D. capensis), summer-fall, shallow, 687.9 (0.52); and Dall's porpoise (Phocoenoides dalli), winter-spring, deep, 48.65 (0.28). Seasonally, density varied significantly by depth for humpback whales, fin whales, and Pacific white-sided dolphins. Article in Journal/Newspaper Balaenoptera musculus Blue whale Fin whale Humpback Whale Megaptera novaeangliae University of California: eScholarship Pacific |
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Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
unknown |
topic |
Agricultural Veterinary and Food Sciences Fisheries Sciences Fisheries |
spellingShingle |
Agricultural Veterinary and Food Sciences Fisheries Sciences Fisheries Douglas, Annie B Calambokidis, John Munger, Lisa M Soldevilla, Melissa S Ferguson, Megan C Havron, Andrea M Camacho, Dominique L Campbell, Greg S Hildebrand, John A Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008 |
topic_facet |
Agricultural Veterinary and Food Sciences Fisheries Sciences Fisheries |
description |
Documenting year-round diversity and distribution of marine mammals off Southern California is important for assessment of effects of potentially harmful anthropogenic activities. Although the waters off Southern California have been surveyed extensively for marine mammals over the past 18 years, such surveys have been periodic and were conducted primarily from summer to fall, thereby missing potential seasonal shifts. We examined seasonal abundance and population density of cetaceans off Southern California from 16 shipboard line-transect surveys conducted quarterly during 2004-08. The study area consisted of 238,494 km2 of coastal, shelf, and pelagic oceanic habitat from nearshore waters to 700 km offshore. Based on 693 encounters of 20 cetacean species, abundance estimates by seasonal period (summer-fall or winter-spring) and depth (shallow: <2000.5 m; deep: ≥2000.5 m) were determined for the 11 most commonly encountered species. The following are values of uncorrected density (individuals/1000 km2, coefficients of variation in parentheses) for the seasonal period and depth with greatest density for a selection of the species in this study: blue whale (Balaenoptera musculus), summer-fall, shallow, 3.2 (0.26); fin whale (B. physalus), summer-fall, shallow, 3.7 (0.30); humpback whale (Megaptera novaeangliae), summer- fall, shallow, 3.1 (0.36); short-beaked common dolphin (Delphinus delphis), summer-fall, shallow, 1319.7 (0.24); long-beaked common dolphin (D. capensis), summer-fall, shallow, 687.9 (0.52); and Dall's porpoise (Phocoenoides dalli), winter-spring, deep, 48.65 (0.28). Seasonally, density varied significantly by depth for humpback whales, fin whales, and Pacific white-sided dolphins. |
format |
Article in Journal/Newspaper |
author |
Douglas, Annie B Calambokidis, John Munger, Lisa M Soldevilla, Melissa S Ferguson, Megan C Havron, Andrea M Camacho, Dominique L Campbell, Greg S Hildebrand, John A |
author_facet |
Douglas, Annie B Calambokidis, John Munger, Lisa M Soldevilla, Melissa S Ferguson, Megan C Havron, Andrea M Camacho, Dominique L Campbell, Greg S Hildebrand, John A |
author_sort |
Douglas, Annie B |
title |
Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008 |
title_short |
Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008 |
title_full |
Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008 |
title_fullStr |
Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008 |
title_full_unstemmed |
Seasonal distribution and abundance of cetaceans off Southern California estimated from CalCOFI cruise data from 2004 to 2008 |
title_sort |
seasonal distribution and abundance of cetaceans off southern california estimated from calcofi cruise data from 2004 to 2008 |
publisher |
eScholarship, University of California |
publishDate |
2014 |
url |
https://escholarship.org/uc/item/680173jb |
op_coverage |
198 - 220 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
Balaenoptera musculus Blue whale Fin whale Humpback Whale Megaptera novaeangliae |
genre_facet |
Balaenoptera musculus Blue whale Fin whale Humpback Whale Megaptera novaeangliae |
op_source |
Fishery Bulletin, vol 112, iss 2-3 |
op_relation |
qt680173jb https://escholarship.org/uc/item/680173jb |
op_rights |
CC-BY |
_version_ |
1787423282302025728 |