The distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters
To provide accurate and precise estimates of abundance for harbour porpoises and other small cetaceans throughout the North Sea and adjacent waters, an intensive shipboard and aerial sightings survey was conducted in July 1994 as part of project SCANS - Small Cetacean Abundance in the North Sea. New...
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ftimr:oai:imr.brage.unit.no:11250/105477 2023-05-15T16:33:29+02:00 The distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters Hammond, Philip S. Benke, Harald Breggren, Per Collet, Anne Heide-Jørgensen, Mads Peter Heimlich-Boran, Sara Leopold, Mardik Øien, Nils 1995 application/pdf http://hdl.handle.net/11250/105477 eng eng ICES ICES CM Documents;1995/N:10 This report is not to be cited without prior reference to the authors http://hdl.handle.net/11250/105477 20 s. harbour porpoise nise marine mammals sjøpattedyr stock assessment bestandsberegning VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ethology: 485 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 Working paper 1995 ftimr 2021-09-23T20:15:36Z To provide accurate and precise estimates of abundance for harbour porpoises and other small cetaceans throughout the North Sea and adjacent waters, an intensive shipboard and aerial sightings survey was conducted in July 1994 as part of project SCANS - Small Cetacean Abundance in the North Sea. New methods of data collection and analysis were developed as part of the project. These methods included estimating g(0) and accounting for animal movement in response to survey ships using data collected from a primary and a tracker platform on each ship, and estimating g(0) for the aerial survey using data collected from two aircraft flying in tandem (one behind the other). The survey area included the North Sea (including waters north to 62°N), Skagerrak, Kattegat, western Baltic Sea, Channel and Celtic Shelf Good weather enabled most of the area to receive excellent survey coverage, but too few data for analysis were collected in the Western Baltic. The three most commonly sighted species were harbour porpoises, whitebeaked dolphins and minke whales. Harbour porpoises were distributed throughout most of the North Sea, Skagerrak, Kattegat and Celtic Shelf. None were seen in the southern tip of the North Sea or the Channel. Whitebeaked dolphins were concentrated between 55° and 60°N, particularly in the western North Sea. Minke whales were seen mostly north of 55°N, particularly in the western North Sea, and on the Celtic Shelf. Common dolphins were seen almost exclusively on the Celtic Shelf. Other small cetacean species encountered in small numbers included whitesided dolphins, bottlenose dolphins, striped dolphins, Risso's dolphins, killer whales and pilot whales. Estimates of abundance for the entire survey area using the new methodology are 352,523 (CV=0.14) [95% Cl: 267,000- 465,000] harbour porpoises, 7,856 (CV=0.30) [95% Cl: 4,000- 13,300] whitebeaked dolphins, and 8,445 (CV=0.24) [95% Cl: 5,000- 13,500] minke whales. Report Harbour porpoise Institute for Marine Research: Brage IMR Celtic Shelf ENVELOPE(-8.000,-8.000,50.000,50.000) Kattegat ENVELOPE(9.692,9.692,63.563,63.563) |
institution |
Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
harbour porpoise nise marine mammals sjøpattedyr stock assessment bestandsberegning VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ethology: 485 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 |
spellingShingle |
harbour porpoise nise marine mammals sjøpattedyr stock assessment bestandsberegning VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ethology: 485 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 Hammond, Philip S. Benke, Harald Breggren, Per Collet, Anne Heide-Jørgensen, Mads Peter Heimlich-Boran, Sara Leopold, Mardik Øien, Nils The distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters |
topic_facet |
harbour porpoise nise marine mammals sjøpattedyr stock assessment bestandsberegning VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ethology: 485 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 |
description |
To provide accurate and precise estimates of abundance for harbour porpoises and other small cetaceans throughout the North Sea and adjacent waters, an intensive shipboard and aerial sightings survey was conducted in July 1994 as part of project SCANS - Small Cetacean Abundance in the North Sea. New methods of data collection and analysis were developed as part of the project. These methods included estimating g(0) and accounting for animal movement in response to survey ships using data collected from a primary and a tracker platform on each ship, and estimating g(0) for the aerial survey using data collected from two aircraft flying in tandem (one behind the other). The survey area included the North Sea (including waters north to 62°N), Skagerrak, Kattegat, western Baltic Sea, Channel and Celtic Shelf Good weather enabled most of the area to receive excellent survey coverage, but too few data for analysis were collected in the Western Baltic. The three most commonly sighted species were harbour porpoises, whitebeaked dolphins and minke whales. Harbour porpoises were distributed throughout most of the North Sea, Skagerrak, Kattegat and Celtic Shelf. None were seen in the southern tip of the North Sea or the Channel. Whitebeaked dolphins were concentrated between 55° and 60°N, particularly in the western North Sea. Minke whales were seen mostly north of 55°N, particularly in the western North Sea, and on the Celtic Shelf. Common dolphins were seen almost exclusively on the Celtic Shelf. Other small cetacean species encountered in small numbers included whitesided dolphins, bottlenose dolphins, striped dolphins, Risso's dolphins, killer whales and pilot whales. Estimates of abundance for the entire survey area using the new methodology are 352,523 (CV=0.14) [95% Cl: 267,000- 465,000] harbour porpoises, 7,856 (CV=0.30) [95% Cl: 4,000- 13,300] whitebeaked dolphins, and 8,445 (CV=0.24) [95% Cl: 5,000- 13,500] minke whales. |
format |
Report |
author |
Hammond, Philip S. Benke, Harald Breggren, Per Collet, Anne Heide-Jørgensen, Mads Peter Heimlich-Boran, Sara Leopold, Mardik Øien, Nils |
author_facet |
Hammond, Philip S. Benke, Harald Breggren, Per Collet, Anne Heide-Jørgensen, Mads Peter Heimlich-Boran, Sara Leopold, Mardik Øien, Nils |
author_sort |
Hammond, Philip S. |
title |
The distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters |
title_short |
The distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters |
title_full |
The distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters |
title_fullStr |
The distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters |
title_full_unstemmed |
The distribution and abundance of harbour porpoises and other small cetaceans in the North Sea and adjacent waters |
title_sort |
distribution and abundance of harbour porpoises and other small cetaceans in the north sea and adjacent waters |
publisher |
ICES |
publishDate |
1995 |
url |
http://hdl.handle.net/11250/105477 |
long_lat |
ENVELOPE(-8.000,-8.000,50.000,50.000) ENVELOPE(9.692,9.692,63.563,63.563) |
geographic |
Celtic Shelf Kattegat |
geographic_facet |
Celtic Shelf Kattegat |
genre |
Harbour porpoise |
genre_facet |
Harbour porpoise |
op_source |
20 s. |
op_relation |
ICES CM Documents;1995/N:10 This report is not to be cited without prior reference to the authors http://hdl.handle.net/11250/105477 |
_version_ |
1766023182392754176 |