Prey consumtion by Barents sea harp seals in the period 1990-2005
The Barents Sea ecosystem has experienced major fluctuations in species abundance in the past 20-30 years. The mechanisms behind these fluctuations are complex and arise from numerous interactions between species and the environment. Previous and present attempts to assess multi-species interactions...
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ftimr:oai:imr.brage.unit.no:11250/100907 2023-05-15T14:30:32+02:00 Prey consumtion by Barents sea harp seals in the period 1990-2005 Lindstrøm, Ulf Nilssen, Kjell Tormod Haug, Tore 2006 220734 bytes application/pdf http://hdl.handle.net/11250/100907 eng eng ICES ICES CM documents 2006/L:08 http://hdl.handle.net/11250/100907 19 s. biodiversity harp seal grønlandssel biologisk mangfold VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ecology: 488 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Working paper 2006 ftimr 2021-09-23T20:15:32Z The Barents Sea ecosystem has experienced major fluctuations in species abundance in the past 20-30 years. The mechanisms behind these fluctuations are complex and arise from numerous interactions between species and the environment. Previous and present attempts to assess multi-species interactions in the Barents sea ecosystem has resulted in increased focus on the foraging ecology of the most conspicuous high trophic-level predators in the ecosystem. The Barents Sea stock of harp seals Pagophilus groenlandicus is, along with Arctic cod Gadus morhua, considered as the most conspicuous high trophic-level predator in the Barents Sea ecosystem. The abundance and feeding ecology of the Barents Sea stock of harp seals has been monitored the past 15 years. Previous prey consumption estimates suggests that harp seals consume range between 3.3 and 5 million tonnes of prey annually, depending on the choice of input parameters in the bioenergetic model. There were a considerable amounnt of uncertainty attached to the input data in the consumption model, in particular the important harp seal diets during summer (May-August). Also, uncertainty estimates of the prey consumption were not given in the previous study. An important objective of this study was to estimate the uncertainty of the prey consumption estimates by using a standard Monte-Carlo framework; random draws from probability distributions of diet and abundance were performed. Additionally, new diet data from May-July has become available and is included in the analysis. The summer consumption was to a large extent dominated by krill, whereas polar cod also contributed importantly. All sampling were performed in a period with low capelin abundance – this may have influenced the results. Report Arctic cod Arctic Barents Sea Gadus morhua Grønlandssel Harp Seal Pagophilus groenlandicus polar cod Institute for Marine Research: Brage IMR Arctic Barents Sea |
institution |
Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
biodiversity harp seal grønlandssel biologisk mangfold VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ecology: 488 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 |
spellingShingle |
biodiversity harp seal grønlandssel biologisk mangfold VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ecology: 488 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Lindstrøm, Ulf Nilssen, Kjell Tormod Haug, Tore Prey consumtion by Barents sea harp seals in the period 1990-2005 |
topic_facet |
biodiversity harp seal grønlandssel biologisk mangfold VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ecology: 488 VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 |
description |
The Barents Sea ecosystem has experienced major fluctuations in species abundance in the past 20-30 years. The mechanisms behind these fluctuations are complex and arise from numerous interactions between species and the environment. Previous and present attempts to assess multi-species interactions in the Barents sea ecosystem has resulted in increased focus on the foraging ecology of the most conspicuous high trophic-level predators in the ecosystem. The Barents Sea stock of harp seals Pagophilus groenlandicus is, along with Arctic cod Gadus morhua, considered as the most conspicuous high trophic-level predator in the Barents Sea ecosystem. The abundance and feeding ecology of the Barents Sea stock of harp seals has been monitored the past 15 years. Previous prey consumption estimates suggests that harp seals consume range between 3.3 and 5 million tonnes of prey annually, depending on the choice of input parameters in the bioenergetic model. There were a considerable amounnt of uncertainty attached to the input data in the consumption model, in particular the important harp seal diets during summer (May-August). Also, uncertainty estimates of the prey consumption were not given in the previous study. An important objective of this study was to estimate the uncertainty of the prey consumption estimates by using a standard Monte-Carlo framework; random draws from probability distributions of diet and abundance were performed. Additionally, new diet data from May-July has become available and is included in the analysis. The summer consumption was to a large extent dominated by krill, whereas polar cod also contributed importantly. All sampling were performed in a period with low capelin abundance – this may have influenced the results. |
format |
Report |
author |
Lindstrøm, Ulf Nilssen, Kjell Tormod Haug, Tore |
author_facet |
Lindstrøm, Ulf Nilssen, Kjell Tormod Haug, Tore |
author_sort |
Lindstrøm, Ulf |
title |
Prey consumtion by Barents sea harp seals in the period 1990-2005 |
title_short |
Prey consumtion by Barents sea harp seals in the period 1990-2005 |
title_full |
Prey consumtion by Barents sea harp seals in the period 1990-2005 |
title_fullStr |
Prey consumtion by Barents sea harp seals in the period 1990-2005 |
title_full_unstemmed |
Prey consumtion by Barents sea harp seals in the period 1990-2005 |
title_sort |
prey consumtion by barents sea harp seals in the period 1990-2005 |
publisher |
ICES |
publishDate |
2006 |
url |
http://hdl.handle.net/11250/100907 |
geographic |
Arctic Barents Sea |
geographic_facet |
Arctic Barents Sea |
genre |
Arctic cod Arctic Barents Sea Gadus morhua Grønlandssel Harp Seal Pagophilus groenlandicus polar cod |
genre_facet |
Arctic cod Arctic Barents Sea Gadus morhua Grønlandssel Harp Seal Pagophilus groenlandicus polar cod |
op_source |
19 s. |
op_relation |
ICES CM documents 2006/L:08 http://hdl.handle.net/11250/100907 |
_version_ |
1766304359239385088 |