Narwhal Abundance in the Eastern Canadian High Arctic in 2013
In summer, narwhals (Monodon monoceros) migrate from Baffin Bay to northeastern Canada and northwest Greenland, where they are hunted by Inuit for subsistence. To prevent localized depletion, management of narwhals is based on summer stocks. The High Arctic Cetacean Survey (HACS), conducted in Augus...
Published in: | NAMMCO Scientific Publications |
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Main Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Septentrio Academic Publishing
2020
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Subjects: | |
Online Access: | https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100 https://doi.org/10.7557/3.5100 |
id |
ftunitroemsoe:oai:ojs.henry.ub.uit.no:article/5100 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
University of Tromsø: Septentrio Academic Publishing |
op_collection_id |
ftunitroemsoe |
language |
English |
topic |
narwhal Baffin Bay summer stocks abundance aerial survey double-platform distance sampling density surface modelling fjords |
spellingShingle |
narwhal Baffin Bay summer stocks abundance aerial survey double-platform distance sampling density surface modelling fjords Doniol-Valcroze, Thomas Gosselin, Jean-François Pike, Daniel G. Lawson, Jack W. Asselin, Natalie C. Hedges, Kevin Ferguson, Steven H. Narwhal Abundance in the Eastern Canadian High Arctic in 2013 |
topic_facet |
narwhal Baffin Bay summer stocks abundance aerial survey double-platform distance sampling density surface modelling fjords |
description |
In summer, narwhals (Monodon monoceros) migrate from Baffin Bay to northeastern Canada and northwest Greenland, where they are hunted by Inuit for subsistence. To prevent localized depletion, management of narwhals is based on summer stocks. The High Arctic Cetacean Survey (HACS), conducted in August 2013, was the first survey to estimate abundance of all 4 Canadian Baffin Bay narwhal summer stocks, as well as putative stocks in Jones Sound and Smith Sound, in the same summer. Narwhal abundance was estimated using a double-platform aerial survey. Distance sampling methods were used to estimate detection probability away from the track line. Mark-recapture methods were used to correct for the proportion of narwhals missed by visual observers on the track line (i.e., perception bias). We used a data-driven approach to identify single and duplicate sightings, using 4 covariates to compare differences in sightings made by front and rear observers based on: time of sighting, declination angle, group size, and species identity. Abundance in fjords was estimated using density surface modelling to account for their complex shape and uneven coverage. Estimates were corrected for availability bias (narwhals that are not available for detection because they are submerged when the aircraft passes overhead) using a new analysis of August dive behaviour data from narwhals equipped with satellite-linked time depth recorders. Corrected abundance estimates were 12,694 (95% CI: 6,324–25,481) for the Jones Sound stock; 16,360 (95% CI: 3,833–69,836) for the Smith Sound stock; 49,768 (95% CI: 32,945–75,182) for the Somerset Island stock; 35,043 (95% CI: 14,188–86,553) for the Admiralty Inlet stock; 10,489 (95% CI: 6,342–17,347) for the Eclipse Sound stock; and 17,555 (95% CI: 8,473–36,373) for the East Baffin Island stock. Total abundance for these 6 stocks was estimated at 141,908 (95% CI: 102,464–196,536). Sources of uncertainty arise from the high level of clustering observed, in particular in Admiralty Inlet, Eclipse Sound, and ... |
format |
Article in Journal/Newspaper |
author |
Doniol-Valcroze, Thomas Gosselin, Jean-François Pike, Daniel G. Lawson, Jack W. Asselin, Natalie C. Hedges, Kevin Ferguson, Steven H. |
author_facet |
Doniol-Valcroze, Thomas Gosselin, Jean-François Pike, Daniel G. Lawson, Jack W. Asselin, Natalie C. Hedges, Kevin Ferguson, Steven H. |
author_sort |
Doniol-Valcroze, Thomas |
title |
Narwhal Abundance in the Eastern Canadian High Arctic in 2013 |
title_short |
Narwhal Abundance in the Eastern Canadian High Arctic in 2013 |
title_full |
Narwhal Abundance in the Eastern Canadian High Arctic in 2013 |
title_fullStr |
Narwhal Abundance in the Eastern Canadian High Arctic in 2013 |
title_full_unstemmed |
Narwhal Abundance in the Eastern Canadian High Arctic in 2013 |
title_sort |
narwhal abundance in the eastern canadian high arctic in 2013 |
publisher |
Septentrio Academic Publishing |
publishDate |
2020 |
url |
https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100 https://doi.org/10.7557/3.5100 |
long_lat |
ENVELOPE(-86.000,-86.000,72.501,72.501) ENVELOPE(-78.998,-78.998,72.635,72.635) ENVELOPE(-86.000,-86.000,76.002,76.002) ENVELOPE(-73.996,-73.996,78.419,78.419) ENVELOPE(-93.500,-93.500,73.251,73.251) |
geographic |
Admiralty Inlet Arctic Baffin Bay Baffin Island Canada Eclipse Sound Greenland Jones Sound Smith Sound Somerset Island |
geographic_facet |
Admiralty Inlet Arctic Baffin Bay Baffin Island Canada Eclipse Sound Greenland Jones Sound Smith Sound Somerset Island |
genre |
Arctic Baffin Bay Baffin Bay Baffin Island Baffin Eclipse Sound Greenland inuit Jones Sound Monodon monoceros narwhal* Smith sound Somerset Island |
genre_facet |
Arctic Baffin Bay Baffin Bay Baffin Island Baffin Eclipse Sound Greenland inuit Jones Sound Monodon monoceros narwhal* Smith sound Somerset Island |
op_source |
NAMMCO Scientific Publications; Vol. 11 (2019): Sightings Surveys in the North Atlantic: 30 years of counting whales 2309-2491 1560-2206 10.7557/3.11 |
op_relation |
https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5444 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5727 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5728 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5729 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5730 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5731 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5732 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5733 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5734 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5735 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5736 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5737 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5738 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5739 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5740 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100 doi:10.7557/3.5100 |
op_rights |
Copyright (c) 2020 Thomas Doniol-Valcroze, Jean-François Gosselin, Daniel G. Pike, Jack W. Lawson, Natalie C. Asselin, Kevin Hedges, Steven H. Ferguson https://creativecommons.org/licenses/by/4.0 |
op_doi |
https://doi.org/10.7557/3.510010.7557/3.11 |
container_title |
NAMMCO Scientific Publications |
container_volume |
11 |
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1779312041220112384 |
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ftunitroemsoe:oai:ojs.henry.ub.uit.no:article/5100 2023-10-09T21:49:00+02:00 Narwhal Abundance in the Eastern Canadian High Arctic in 2013 Doniol-Valcroze, Thomas Gosselin, Jean-François Pike, Daniel G. Lawson, Jack W. Asselin, Natalie C. Hedges, Kevin Ferguson, Steven H. 2020-11-27 application/pdf image/png image/tiff image/jpeg https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100 https://doi.org/10.7557/3.5100 eng eng Septentrio Academic Publishing https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5444 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5727 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5728 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5729 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5730 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5731 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5732 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5733 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5734 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5735 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5736 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5737 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5738 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5739 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100/5740 https://septentrio.uit.no/index.php/NAMMCOSP/article/view/5100 doi:10.7557/3.5100 Copyright (c) 2020 Thomas Doniol-Valcroze, Jean-François Gosselin, Daniel G. Pike, Jack W. Lawson, Natalie C. Asselin, Kevin Hedges, Steven H. Ferguson https://creativecommons.org/licenses/by/4.0 NAMMCO Scientific Publications; Vol. 11 (2019): Sightings Surveys in the North Atlantic: 30 years of counting whales 2309-2491 1560-2206 10.7557/3.11 narwhal Baffin Bay summer stocks abundance aerial survey double-platform distance sampling density surface modelling fjords info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2020 ftunitroemsoe https://doi.org/10.7557/3.510010.7557/3.11 2023-09-20T23:07:55Z In summer, narwhals (Monodon monoceros) migrate from Baffin Bay to northeastern Canada and northwest Greenland, where they are hunted by Inuit for subsistence. To prevent localized depletion, management of narwhals is based on summer stocks. The High Arctic Cetacean Survey (HACS), conducted in August 2013, was the first survey to estimate abundance of all 4 Canadian Baffin Bay narwhal summer stocks, as well as putative stocks in Jones Sound and Smith Sound, in the same summer. Narwhal abundance was estimated using a double-platform aerial survey. Distance sampling methods were used to estimate detection probability away from the track line. Mark-recapture methods were used to correct for the proportion of narwhals missed by visual observers on the track line (i.e., perception bias). We used a data-driven approach to identify single and duplicate sightings, using 4 covariates to compare differences in sightings made by front and rear observers based on: time of sighting, declination angle, group size, and species identity. Abundance in fjords was estimated using density surface modelling to account for their complex shape and uneven coverage. Estimates were corrected for availability bias (narwhals that are not available for detection because they are submerged when the aircraft passes overhead) using a new analysis of August dive behaviour data from narwhals equipped with satellite-linked time depth recorders. Corrected abundance estimates were 12,694 (95% CI: 6,324–25,481) for the Jones Sound stock; 16,360 (95% CI: 3,833–69,836) for the Smith Sound stock; 49,768 (95% CI: 32,945–75,182) for the Somerset Island stock; 35,043 (95% CI: 14,188–86,553) for the Admiralty Inlet stock; 10,489 (95% CI: 6,342–17,347) for the Eclipse Sound stock; and 17,555 (95% CI: 8,473–36,373) for the East Baffin Island stock. Total abundance for these 6 stocks was estimated at 141,908 (95% CI: 102,464–196,536). Sources of uncertainty arise from the high level of clustering observed, in particular in Admiralty Inlet, Eclipse Sound, and ... Article in Journal/Newspaper Arctic Baffin Bay Baffin Bay Baffin Island Baffin Eclipse Sound Greenland inuit Jones Sound Monodon monoceros narwhal* Smith sound Somerset Island University of Tromsø: Septentrio Academic Publishing Admiralty Inlet ENVELOPE(-86.000,-86.000,72.501,72.501) Arctic Baffin Bay Baffin Island Canada Eclipse Sound ENVELOPE(-78.998,-78.998,72.635,72.635) Greenland Jones Sound ENVELOPE(-86.000,-86.000,76.002,76.002) Smith Sound ENVELOPE(-73.996,-73.996,78.419,78.419) Somerset Island ENVELOPE(-93.500,-93.500,73.251,73.251) NAMMCO Scientific Publications 11 |