Fish consumption by great cormorants in Norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids
Piscivorous wildlife is often perceived as competitors by humans. Great cormorants of the continental subspecies (Phalacrocorax carbo sinensis) in the Baltic and North Sea increase, while local cod (Gadus morhua) stocks decline. In contrast, numbers of the Atlantic subspecies (Phalacrocorax carbo ca...
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Online Access: | https://hdl.handle.net/11250/2728312 https://doi.org/10.1093/icesjms/fsab004 |
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ftimr:oai:imr.brage.unit.no:11250/2728312 2024-09-15T18:07:16+00:00 Fish consumption by great cormorants in Norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids Dehnhard, Nina Langset, Magdalene Aglen, Asgeir Lorentsen, Svein-Håkon Anker-Nilssen, Tycho 2021 application/pdf https://hdl.handle.net/11250/2728312 https://doi.org/10.1093/icesjms/fsab004 eng eng Andre: Norwegian Environment Agency Andre: Norwegian Oil and Gas Association Norges forskningsråd: 192141 urn:issn:1054-3139 https://hdl.handle.net/11250/2728312 https://doi.org/10.1093/icesjms/fsab004 cristin:1889765 ICES Journal of Marine Science VDP::Zoologiske og botaniske fag: 480 VDP::Zoology and botany: 480 Peer reviewed Journal article 2021 ftimr https://doi.org/10.1093/icesjms/fsab004 2024-07-31T03:37:25Z Piscivorous wildlife is often perceived as competitors by humans. Great cormorants of the continental subspecies (Phalacrocorax carbo sinensis) in the Baltic and North Sea increase, while local cod (Gadus morhua) stocks decline. In contrast, numbers of the Atlantic subspecies (Phalacrocorax carbo carbo), breeding along the Norwegian and Barents Seas, have been relatively stable. We investigated the diet of both great cormorant subspecies in breeding colonies along the Norwegian Coast from Lofoten to the Skagerrak and estimated the biomass of fish consumed annually by great cormorants in Norwegian waters. The birds’ consumption was compared with estimated fish stock sizes and fishery catches. Cod and saithe (Pollachius virens) dominated the diet in the Norwegian Sea and wrasses in the North Sea and Skagerrak. Estimated total fish consumption of cod and saithe by great cormorants was <1.7% of estimated fish stocks and <9% of that of human catches and therefore considered minor. Cormorant consumption of wrasses amounted to 110% of human catches. The practice of using wrasses as cleaner fish in the salmon farming industry leads to a conflict with cormorants, and we urge for a better understanding and management of wrasse populations, taking ecosystem functioning and natural predation into account. diet analysis, fish stock size, Gadus morhua, Labridae, metabolic rate, North Atlantic, Norway publishedVersion Article in Journal/Newspaper Gadus morhua Lofoten North Atlantic Norwegian Sea Institute for Marine Research: Brage IMR ICES Journal of Marine Science |
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Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
VDP::Zoologiske og botaniske fag: 480 VDP::Zoology and botany: 480 |
spellingShingle |
VDP::Zoologiske og botaniske fag: 480 VDP::Zoology and botany: 480 Dehnhard, Nina Langset, Magdalene Aglen, Asgeir Lorentsen, Svein-Håkon Anker-Nilssen, Tycho Fish consumption by great cormorants in Norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids |
topic_facet |
VDP::Zoologiske og botaniske fag: 480 VDP::Zoology and botany: 480 |
description |
Piscivorous wildlife is often perceived as competitors by humans. Great cormorants of the continental subspecies (Phalacrocorax carbo sinensis) in the Baltic and North Sea increase, while local cod (Gadus morhua) stocks decline. In contrast, numbers of the Atlantic subspecies (Phalacrocorax carbo carbo), breeding along the Norwegian and Barents Seas, have been relatively stable. We investigated the diet of both great cormorant subspecies in breeding colonies along the Norwegian Coast from Lofoten to the Skagerrak and estimated the biomass of fish consumed annually by great cormorants in Norwegian waters. The birds’ consumption was compared with estimated fish stock sizes and fishery catches. Cod and saithe (Pollachius virens) dominated the diet in the Norwegian Sea and wrasses in the North Sea and Skagerrak. Estimated total fish consumption of cod and saithe by great cormorants was <1.7% of estimated fish stocks and <9% of that of human catches and therefore considered minor. Cormorant consumption of wrasses amounted to 110% of human catches. The practice of using wrasses as cleaner fish in the salmon farming industry leads to a conflict with cormorants, and we urge for a better understanding and management of wrasse populations, taking ecosystem functioning and natural predation into account. diet analysis, fish stock size, Gadus morhua, Labridae, metabolic rate, North Atlantic, Norway publishedVersion |
format |
Article in Journal/Newspaper |
author |
Dehnhard, Nina Langset, Magdalene Aglen, Asgeir Lorentsen, Svein-Håkon Anker-Nilssen, Tycho |
author_facet |
Dehnhard, Nina Langset, Magdalene Aglen, Asgeir Lorentsen, Svein-Håkon Anker-Nilssen, Tycho |
author_sort |
Dehnhard, Nina |
title |
Fish consumption by great cormorants in Norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids |
title_short |
Fish consumption by great cormorants in Norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids |
title_full |
Fish consumption by great cormorants in Norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids |
title_fullStr |
Fish consumption by great cormorants in Norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids |
title_full_unstemmed |
Fish consumption by great cormorants in Norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids |
title_sort |
fish consumption by great cormorants in norwegian coastal waters—a human-wildlife conflict for wrasses, but not gadids |
publishDate |
2021 |
url |
https://hdl.handle.net/11250/2728312 https://doi.org/10.1093/icesjms/fsab004 |
genre |
Gadus morhua Lofoten North Atlantic Norwegian Sea |
genre_facet |
Gadus morhua Lofoten North Atlantic Norwegian Sea |
op_source |
ICES Journal of Marine Science |
op_relation |
Andre: Norwegian Environment Agency Andre: Norwegian Oil and Gas Association Norges forskningsråd: 192141 urn:issn:1054-3139 https://hdl.handle.net/11250/2728312 https://doi.org/10.1093/icesjms/fsab004 cristin:1889765 |
op_doi |
https://doi.org/10.1093/icesjms/fsab004 |
container_title |
ICES Journal of Marine Science |
_version_ |
1810444646921273344 |