Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space
Regional sighting surveys with two independent observers on each vessel were conducted each year from 1996 to 2001. Northern minke whales (Balaenoptera acutorostrata) are mostly solitary animals and are only available for observation at moments when they surface to breath. Thus, a stochastic point p...
Published in: | Canadian Journal of Fisheries and Aquatic Sciences |
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Online Access: | http://hdl.handle.net/11250/108296 https://doi.org/10.1139/F04-020 |
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ftimr:oai:imr.brage.unit.no:11250/108296 2023-05-15T15:36:05+02:00 Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space Skaug, Hans Julius Øien, Nils Schweder, Tore Bøthun, Gjermund 2004 727410 bytes application/pdf http://hdl.handle.net/11250/108296 https://doi.org/10.1139/F04-020 eng eng urn:issn:0706-652X http://hdl.handle.net/11250/108296 http://dx.doi.org/10.1139/F04-020 870–886 61 Canadian Journal of Fisheries and Aquatic Sciences 6 minke whale vågehval bestandsvurderinger abundance estimates Journal article Peer reviewed 2004 ftimr https://doi.org/10.1139/F04-020 2021-09-23T20:14:34Z Regional sighting surveys with two independent observers on each vessel were conducted each year from 1996 to 2001. Northern minke whales (Balaenoptera acutorostrata) are mostly solitary animals and are only available for observation at moments when they surface to breath. Thus, a stochastic point process model is developed for how the data are generated. The hazard probability of initially sighting a whale that surfaces depends on relative spatial coordinates and on other covariates. The parameters of the model are estimated by maximum likelihood. To account for interannual variation in spatial distribution of minke whales, a random effects model is developed and estimated by comparing current and past (1989 and 1995) survey data. A simulation approach is taken to remove bias from parameter estimates and to assess the uncertainty in the results. For total abundance, the result is a log-normal confidence distribution with quantiles 107 205·exp(0.137z), i.e., an abundance estimate of 107 205 with a coefficient of variation of ≈0.14. Together with these and earlier survey data, past data on catch, mark–recapture, and satellite tracking are reviewed to elucidate distribution and migration patterns in Northeastern Atlantic minke whales. Article in Journal/Newspaper Balaenoptera acutorostrata minke whale Northeast Atlantic vågehval Institute for Marine Research: Brage IMR Canadian Journal of Fisheries and Aquatic Sciences 61 6 870 886 |
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Open Polar |
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Institute for Marine Research: Brage IMR |
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ftimr |
language |
English |
topic |
minke whale vågehval bestandsvurderinger abundance estimates |
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minke whale vågehval bestandsvurderinger abundance estimates Skaug, Hans Julius Øien, Nils Schweder, Tore Bøthun, Gjermund Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space |
topic_facet |
minke whale vågehval bestandsvurderinger abundance estimates |
description |
Regional sighting surveys with two independent observers on each vessel were conducted each year from 1996 to 2001. Northern minke whales (Balaenoptera acutorostrata) are mostly solitary animals and are only available for observation at moments when they surface to breath. Thus, a stochastic point process model is developed for how the data are generated. The hazard probability of initially sighting a whale that surfaces depends on relative spatial coordinates and on other covariates. The parameters of the model are estimated by maximum likelihood. To account for interannual variation in spatial distribution of minke whales, a random effects model is developed and estimated by comparing current and past (1989 and 1995) survey data. A simulation approach is taken to remove bias from parameter estimates and to assess the uncertainty in the results. For total abundance, the result is a log-normal confidence distribution with quantiles 107 205·exp(0.137z), i.e., an abundance estimate of 107 205 with a coefficient of variation of ≈0.14. Together with these and earlier survey data, past data on catch, mark–recapture, and satellite tracking are reviewed to elucidate distribution and migration patterns in Northeastern Atlantic minke whales. |
format |
Article in Journal/Newspaper |
author |
Skaug, Hans Julius Øien, Nils Schweder, Tore Bøthun, Gjermund |
author_facet |
Skaug, Hans Julius Øien, Nils Schweder, Tore Bøthun, Gjermund |
author_sort |
Skaug, Hans Julius |
title |
Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space |
title_short |
Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space |
title_full |
Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space |
title_fullStr |
Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space |
title_full_unstemmed |
Abundance of minke whales (Balaenoptera acutorostrata) in the Northeast Atlantic: variability in time and space |
title_sort |
abundance of minke whales (balaenoptera acutorostrata) in the northeast atlantic: variability in time and space |
publishDate |
2004 |
url |
http://hdl.handle.net/11250/108296 https://doi.org/10.1139/F04-020 |
genre |
Balaenoptera acutorostrata minke whale Northeast Atlantic vågehval |
genre_facet |
Balaenoptera acutorostrata minke whale Northeast Atlantic vågehval |
op_source |
870–886 61 Canadian Journal of Fisheries and Aquatic Sciences 6 |
op_relation |
urn:issn:0706-652X http://hdl.handle.net/11250/108296 http://dx.doi.org/10.1139/F04-020 |
op_doi |
https://doi.org/10.1139/F04-020 |
container_title |
Canadian Journal of Fisheries and Aquatic Sciences |
container_volume |
61 |
container_issue |
6 |
container_start_page |
870 |
op_container_end_page |
886 |
_version_ |
1766366426062389248 |