Trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the Barents Sea capelin
In the Barents Sea, capelin is a key food item for the North-East Arctic cod stock. This capelin stock has had very unstable population dynamics since 1985, with recruitment failures leading to three major collapses of the stock (>90% reduction of the stock size), resulting in decreased growth an...
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ftimr:oai:imr.brage.unit.no:11250/102938 2023-05-15T14:30:30+02:00 Trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the Barents Sea capelin Hjermann, Dag Ø. Bogstad, Bjarte Dingsør, Gjert Endre Gjøsæter, Harald Ottersen, Geir Eikeset, Anne Maria Stenseth, Nils Christian 2009 application/pdf http://hdl.handle.net/11250/102938 eng eng ICES ICES CM documents;2009/ C:07 This report is not to be quoted without prior consultation with the General Secretary. http://hdl.handle.net/11250/102938 10 s. capelin lodde stock collapse bestandssammenbrudd VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 Working paper 2009 ftimr 2021-09-23T20:16:16Z In the Barents Sea, capelin is a key food item for the North-East Arctic cod stock. This capelin stock has had very unstable population dynamics since 1985, with recruitment failures leading to three major collapses of the stock (>90% reduction of the stock size), resulting in decreased growth and survival of cod. Here we analyze in detail how predation and harvest affects the recruitment of capelin, using data on three different stages (i.e., larvae, zero-group and 1-year-olds) through the first 1.5 years of the capelin's life. We demonstrate that both herring predation (on capelin larvae) and cod predation (both on spawners and on offspring) has had major negative effects on capelin recruitment. Mortality is furthermore demonstrated to be strongly density-dependent, and is lower when temperatures are high – probably due to higher food availability for capelin. Harvesting maturing capelin on the way to the spawning grounds did affect the production of larvae, at least during the first half of the 1980s. However, the reduced production of larvae appears to a large extent to have been compensated by decreased density-dependent mortality on later life-stages, resulting in only minor effects on the abundance as 1-year-olds. Altogether, our study points to the importance of trophic interactions in determining the dynamic structure in high-latitude marine ecosystems. Keywords: stock collapse, predation, trophic interactions, harvesting, density-dependent mortality, Generalized Additive Models (GAM) Report Arctic cod Arctic Barents Sea Institute for Marine Research: Brage IMR Arctic Barents Sea Gam ENVELOPE(-57.955,-57.955,-61.923,-61.923) |
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Open Polar |
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Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
capelin lodde stock collapse bestandssammenbrudd VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 |
spellingShingle |
capelin lodde stock collapse bestandssammenbrudd VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 Hjermann, Dag Ø. Bogstad, Bjarte Dingsør, Gjert Endre Gjøsæter, Harald Ottersen, Geir Eikeset, Anne Maria Stenseth, Nils Christian Trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the Barents Sea capelin |
topic_facet |
capelin lodde stock collapse bestandssammenbrudd VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 |
description |
In the Barents Sea, capelin is a key food item for the North-East Arctic cod stock. This capelin stock has had very unstable population dynamics since 1985, with recruitment failures leading to three major collapses of the stock (>90% reduction of the stock size), resulting in decreased growth and survival of cod. Here we analyze in detail how predation and harvest affects the recruitment of capelin, using data on three different stages (i.e., larvae, zero-group and 1-year-olds) through the first 1.5 years of the capelin's life. We demonstrate that both herring predation (on capelin larvae) and cod predation (both on spawners and on offspring) has had major negative effects on capelin recruitment. Mortality is furthermore demonstrated to be strongly density-dependent, and is lower when temperatures are high – probably due to higher food availability for capelin. Harvesting maturing capelin on the way to the spawning grounds did affect the production of larvae, at least during the first half of the 1980s. However, the reduced production of larvae appears to a large extent to have been compensated by decreased density-dependent mortality on later life-stages, resulting in only minor effects on the abundance as 1-year-olds. Altogether, our study points to the importance of trophic interactions in determining the dynamic structure in high-latitude marine ecosystems. Keywords: stock collapse, predation, trophic interactions, harvesting, density-dependent mortality, Generalized Additive Models (GAM) |
format |
Report |
author |
Hjermann, Dag Ø. Bogstad, Bjarte Dingsør, Gjert Endre Gjøsæter, Harald Ottersen, Geir Eikeset, Anne Maria Stenseth, Nils Christian |
author_facet |
Hjermann, Dag Ø. Bogstad, Bjarte Dingsør, Gjert Endre Gjøsæter, Harald Ottersen, Geir Eikeset, Anne Maria Stenseth, Nils Christian |
author_sort |
Hjermann, Dag Ø. |
title |
Trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the Barents Sea capelin |
title_short |
Trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the Barents Sea capelin |
title_full |
Trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the Barents Sea capelin |
title_fullStr |
Trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the Barents Sea capelin |
title_full_unstemmed |
Trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the Barents Sea capelin |
title_sort |
trophic interactions affecting a key ecosystem component: a multi-stage analysis of the recruitment of the barents sea capelin |
publisher |
ICES |
publishDate |
2009 |
url |
http://hdl.handle.net/11250/102938 |
long_lat |
ENVELOPE(-57.955,-57.955,-61.923,-61.923) |
geographic |
Arctic Barents Sea Gam |
geographic_facet |
Arctic Barents Sea Gam |
genre |
Arctic cod Arctic Barents Sea |
genre_facet |
Arctic cod Arctic Barents Sea |
op_source |
10 s. |
op_relation |
ICES CM documents;2009/ C:07 This report is not to be quoted without prior consultation with the General Secretary. http://hdl.handle.net/11250/102938 |
_version_ |
1766304341689368576 |