Harp seal (Phoca Groenlandica) invasions in north Norwegian coastal waters: A preliminary report on age composition and feeding habits
Since 1978 large numbers of harp seals (Phoca groenlandica) have invaded areas of North Norway in winter and spring. In 1987 and 1988 dramatic increases occurred both in magnitude and geographic extent of these seal invasions, and it is suggested that the collapse of the Barents Sea capelin stock in...
Main Authors: | , , , |
---|---|
Format: | Report |
Language: | English |
Published: |
ICES
1990
|
Subjects: | |
Online Access: | http://hdl.handle.net/11250/104807 |
id |
ftimr:oai:imr.brage.unit.no:11250/104807 |
---|---|
record_format |
openpolar |
spelling |
ftimr:oai:imr.brage.unit.no:11250/104807 2023-05-15T15:38:57+02:00 Harp seal (Phoca Groenlandica) invasions in north Norwegian coastal waters: A preliminary report on age composition and feeding habits Haug, Tore Krøyer, Ari B. Nilssen, Kjell Tormod Ugland, Karl Inne 1990 application/pdf http://hdl.handle.net/11250/104807 eng eng ICES ICES CM Documents;1990/N:6 This report is not to be cited without prior reference to the authors http://hdl.handle.net/11250/104807 24 s. harp seal grønlandssel stomach data magedata feeding fôring VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 Working paper 1990 ftimr 2021-09-23T20:14:30Z Since 1978 large numbers of harp seals (Phoca groenlandica) have invaded areas of North Norway in winter and spring. In 1987 and 1988 dramatic increases occurred both in magnitude and geographic extent of these seal invasions, and it is suggested that the collapse of the Barents Sea capelin stock in 1985/1986 may have been a contributory factor to this. Sampling of stomach contents for food analyses and of teeth for age determinations was carried out from harp seals taken as bycatch in Norwegian gill-net fisheries in 1986 and 1988. It appears that the seal herds comprised both immature and mature animals. The stomach analyses suggested that feeding was opportunistic, with a variety of fish (in particular the gadoid species cod, saithe, haddock and Norway pout, and the pelagic shoaling species herring and capelin) being taken as prey. Prawns and squid were also consumed, but in considerably lower quantities than fish. Report Barents Sea Grønlandssel Harp Seal North Norway Phoca groenlandica Institute for Marine Research: Brage IMR Barents Sea Norway |
institution |
Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
harp seal grønlandssel stomach data magedata feeding fôring VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 |
spellingShingle |
harp seal grønlandssel stomach data magedata feeding fôring VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 Haug, Tore Krøyer, Ari B. Nilssen, Kjell Tormod Ugland, Karl Inne Harp seal (Phoca Groenlandica) invasions in north Norwegian coastal waters: A preliminary report on age composition and feeding habits |
topic_facet |
harp seal grønlandssel stomach data magedata feeding fôring VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920::Resource biology: 921 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 |
description |
Since 1978 large numbers of harp seals (Phoca groenlandica) have invaded areas of North Norway in winter and spring. In 1987 and 1988 dramatic increases occurred both in magnitude and geographic extent of these seal invasions, and it is suggested that the collapse of the Barents Sea capelin stock in 1985/1986 may have been a contributory factor to this. Sampling of stomach contents for food analyses and of teeth for age determinations was carried out from harp seals taken as bycatch in Norwegian gill-net fisheries in 1986 and 1988. It appears that the seal herds comprised both immature and mature animals. The stomach analyses suggested that feeding was opportunistic, with a variety of fish (in particular the gadoid species cod, saithe, haddock and Norway pout, and the pelagic shoaling species herring and capelin) being taken as prey. Prawns and squid were also consumed, but in considerably lower quantities than fish. |
format |
Report |
author |
Haug, Tore Krøyer, Ari B. Nilssen, Kjell Tormod Ugland, Karl Inne |
author_facet |
Haug, Tore Krøyer, Ari B. Nilssen, Kjell Tormod Ugland, Karl Inne |
author_sort |
Haug, Tore |
title |
Harp seal (Phoca Groenlandica) invasions in north Norwegian coastal waters: A preliminary report on age composition and feeding habits |
title_short |
Harp seal (Phoca Groenlandica) invasions in north Norwegian coastal waters: A preliminary report on age composition and feeding habits |
title_full |
Harp seal (Phoca Groenlandica) invasions in north Norwegian coastal waters: A preliminary report on age composition and feeding habits |
title_fullStr |
Harp seal (Phoca Groenlandica) invasions in north Norwegian coastal waters: A preliminary report on age composition and feeding habits |
title_full_unstemmed |
Harp seal (Phoca Groenlandica) invasions in north Norwegian coastal waters: A preliminary report on age composition and feeding habits |
title_sort |
harp seal (phoca groenlandica) invasions in north norwegian coastal waters: a preliminary report on age composition and feeding habits |
publisher |
ICES |
publishDate |
1990 |
url |
http://hdl.handle.net/11250/104807 |
geographic |
Barents Sea Norway |
geographic_facet |
Barents Sea Norway |
genre |
Barents Sea Grønlandssel Harp Seal North Norway Phoca groenlandica |
genre_facet |
Barents Sea Grønlandssel Harp Seal North Norway Phoca groenlandica |
op_source |
24 s. |
op_relation |
ICES CM Documents;1990/N:6 This report is not to be cited without prior reference to the authors http://hdl.handle.net/11250/104807 |
_version_ |
1766370378619289600 |