Comparative feeding ecology of the sympatric cod fishes Arctogadus glacialis and Boreogadus saida in North East Greenland evaluated from diet and stable isotope analyses
The fish fauna was investigated in autumn 2003 during the TUNU-I Expedition to NE Greenland fjords. Two gadoids Arctogadus glacialis and Boreogadus saida were abundant in many trawl hauls. In this study, the stomach contents and the stable isotope composition were determined in 60 Arctogadus glacial...
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Universitetet i Tromsø
2008
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ftunivtroemsoe:oai:munin.uit.no:10037/1410 2024-06-02T08:02:58+00:00 Comparative feeding ecology of the sympatric cod fishes Arctogadus glacialis and Boreogadus saida in North East Greenland evaluated from diet and stable isotope analyses Joensen, John 2008-02-15 1164450 bytes 2064 bytes application/pdf text/plain https://hdl.handle.net/10037/1410 eng eng Universitetet i Tromsø University of Tromsø https://hdl.handle.net/10037/1410 URN:NBN:no-uit_munin_1191 openAccess Copyright 2008 The Author(s) VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Boreogadus Arctogadus Stable isotopes NE Greenland BIO-3950 Master thesis Mastergradsoppgave 2008 ftunivtroemsoe 2024-05-07T08:41:49Z The fish fauna was investigated in autumn 2003 during the TUNU-I Expedition to NE Greenland fjords. Two gadoids Arctogadus glacialis and Boreogadus saida were abundant in many trawl hauls. In this study, the stomach contents and the stable isotope composition were determined in 60 Arctogadus glacialis and 50 Boreogadus saida from Tyrolerfjord and Dove Bugt. The diets were examined by Stomach Contents Analysis (SCA) and compared with chi-square test and Schoener index. The diets were similar containing the same prey species, mostly crustaceans (copepods, mysids and amphipods). Significant differences were found, mainly in the proportions of two crustaceans, the mysid Mysis oculata and the copepod Metridia longa. Fish was found in the stomachs of large Arctogadus glacialis. The stable isotope composition was analyzed with Stable Isotope Analysis (SIA). Differences were discovered between species and fjords. Arctogadus glacialis had δ13C mean of -20.81 and -21.33‰, δ15N mean of 14.92 and 14.21‰, in Tyrolerfjord and Dove Bugt, respectively. Boreogadus saida had δ13C mean of -21.25 and -21.52‰, δ15N mean of 13.64 and 14.47‰ in the respective fjords. Trophic levels of the species were inferred from mean δ15N-values. The mean δ13C and δ15N values for the predators corresponded well with those of the prey species from the literature, with an enrichment value of 3.8‰ for δ15N. This is the first study that examines the isotope signature and trophical position of Arctogadus glacialis. Master Thesis Arctogadus glacialis Boreogadus saida Dove bugt East Greenland Greenland Tunu Copepods University of Tromsø: Munin Open Research Archive Dove Bugt ENVELOPE(-20.407,-20.407,76.712,76.712) Greenland Tyrolerfjord ENVELOPE(-21.883,-21.883,74.517,74.517) |
institution |
Open Polar |
collection |
University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
topic |
VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Boreogadus Arctogadus Stable isotopes NE Greenland BIO-3950 |
spellingShingle |
VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Boreogadus Arctogadus Stable isotopes NE Greenland BIO-3950 Joensen, John Comparative feeding ecology of the sympatric cod fishes Arctogadus glacialis and Boreogadus saida in North East Greenland evaluated from diet and stable isotope analyses |
topic_facet |
VDP::Agriculture and fishery disciplines: 900::Fisheries science: 920 Boreogadus Arctogadus Stable isotopes NE Greenland BIO-3950 |
description |
The fish fauna was investigated in autumn 2003 during the TUNU-I Expedition to NE Greenland fjords. Two gadoids Arctogadus glacialis and Boreogadus saida were abundant in many trawl hauls. In this study, the stomach contents and the stable isotope composition were determined in 60 Arctogadus glacialis and 50 Boreogadus saida from Tyrolerfjord and Dove Bugt. The diets were examined by Stomach Contents Analysis (SCA) and compared with chi-square test and Schoener index. The diets were similar containing the same prey species, mostly crustaceans (copepods, mysids and amphipods). Significant differences were found, mainly in the proportions of two crustaceans, the mysid Mysis oculata and the copepod Metridia longa. Fish was found in the stomachs of large Arctogadus glacialis. The stable isotope composition was analyzed with Stable Isotope Analysis (SIA). Differences were discovered between species and fjords. Arctogadus glacialis had δ13C mean of -20.81 and -21.33‰, δ15N mean of 14.92 and 14.21‰, in Tyrolerfjord and Dove Bugt, respectively. Boreogadus saida had δ13C mean of -21.25 and -21.52‰, δ15N mean of 13.64 and 14.47‰ in the respective fjords. Trophic levels of the species were inferred from mean δ15N-values. The mean δ13C and δ15N values for the predators corresponded well with those of the prey species from the literature, with an enrichment value of 3.8‰ for δ15N. This is the first study that examines the isotope signature and trophical position of Arctogadus glacialis. |
format |
Master Thesis |
author |
Joensen, John |
author_facet |
Joensen, John |
author_sort |
Joensen, John |
title |
Comparative feeding ecology of the sympatric cod fishes Arctogadus glacialis and Boreogadus saida in North East Greenland evaluated from diet and stable isotope analyses |
title_short |
Comparative feeding ecology of the sympatric cod fishes Arctogadus glacialis and Boreogadus saida in North East Greenland evaluated from diet and stable isotope analyses |
title_full |
Comparative feeding ecology of the sympatric cod fishes Arctogadus glacialis and Boreogadus saida in North East Greenland evaluated from diet and stable isotope analyses |
title_fullStr |
Comparative feeding ecology of the sympatric cod fishes Arctogadus glacialis and Boreogadus saida in North East Greenland evaluated from diet and stable isotope analyses |
title_full_unstemmed |
Comparative feeding ecology of the sympatric cod fishes Arctogadus glacialis and Boreogadus saida in North East Greenland evaluated from diet and stable isotope analyses |
title_sort |
comparative feeding ecology of the sympatric cod fishes arctogadus glacialis and boreogadus saida in north east greenland evaluated from diet and stable isotope analyses |
publisher |
Universitetet i Tromsø |
publishDate |
2008 |
url |
https://hdl.handle.net/10037/1410 |
long_lat |
ENVELOPE(-20.407,-20.407,76.712,76.712) ENVELOPE(-21.883,-21.883,74.517,74.517) |
geographic |
Dove Bugt Greenland Tyrolerfjord |
geographic_facet |
Dove Bugt Greenland Tyrolerfjord |
genre |
Arctogadus glacialis Boreogadus saida Dove bugt East Greenland Greenland Tunu Copepods |
genre_facet |
Arctogadus glacialis Boreogadus saida Dove bugt East Greenland Greenland Tunu Copepods |
op_relation |
https://hdl.handle.net/10037/1410 URN:NBN:no-uit_munin_1191 |
op_rights |
openAccess Copyright 2008 The Author(s) |
_version_ |
1800747430502727680 |