Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak : Effects of body size on short-term movement patterns in nearshore habitats
The coastal cod is an important commercial and recreational resource for the local communities in the Skagerrak. The situation of this and neighbouring stocks has worsened for decades, promoting an imperative need for better knowledge of the fine-scale ecology and behaviour of the species. In this s...
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ftoslouniv:oai:www.duo.uio.no:10852/11738 2023-05-15T16:19:15+02:00 Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak : Effects of body size on short-term movement patterns in nearshore habitats Thoresen, Adine Guldborg Nils Christian Stenseth, Esben Moland Olsen, Sigurd Heiberg Espeland 2008 http://hdl.handle.net/10852/11738 http://urn.nb.no/URN:NBN:no-19260 eng eng http://urn.nb.no/URN:NBN:no-19260 Thoresen, Adine Guldborg. Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak. Masteroppgave, University of Oslo, 2008 http://hdl.handle.net/10852/11738 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Thoresen, Adine Guldborg&rft.title=Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak&rft.inst=University of Oslo&rft.date=2008&rft.degree=Masteroppgave URN:NBN:no-19260 77501 081008708 Fulltext https://www.duo.uio.no/bitstream/handle/10852/11738/2/MasterxthesisxAdinexGuldborgxThoresen.pdf torsk habitatseleksjon juvenil adferd home range VDP::488 Master thesis Masteroppgave 2008 ftoslouniv 2020-06-21T08:41:59Z The coastal cod is an important commercial and recreational resource for the local communities in the Skagerrak. The situation of this and neighbouring stocks has worsened for decades, promoting an imperative need for better knowledge of the fine-scale ecology and behaviour of the species. In this study, the home ranges and vertical movement pattern of nearshore juveniles (n = 20, length = 325 mm [mean]; 265 - 375 mm [range]) were investigated using acoustic telemetry and kernel density estimators. In addition, habitat preferences were estimated by use of resource selection functions. In concordance with the hypotheses, home range sizes increased with fish length, whereas bigger fish remained at shallower depths than smaller fish. Although inconclusive, results were indicative of smaller fish displaying greater variation in vertical movement than larger fish. The fish used habitats disproportionately to what was available, and although tests were not significant the results showed a clear trend of selecting barren habitats over more complex habitat structures. These behavioural patterns are thought to reflect a dynamic decision-making process where intra- and inter-specific competition and predation pressure drive the selection of the trade-off between shelter and forage. Further, these results show that the classification of important habitats for a commercially exploited species is a complex process that should be investigated on a broader scale. Master Thesis Gadus morhua Universitet i Oslo: Digitale utgivelser ved UiO (DUO) |
institution |
Open Polar |
collection |
Universitet i Oslo: Digitale utgivelser ved UiO (DUO) |
op_collection_id |
ftoslouniv |
language |
English |
topic |
torsk habitatseleksjon juvenil adferd home range VDP::488 |
spellingShingle |
torsk habitatseleksjon juvenil adferd home range VDP::488 Thoresen, Adine Guldborg Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak : Effects of body size on short-term movement patterns in nearshore habitats |
topic_facet |
torsk habitatseleksjon juvenil adferd home range VDP::488 |
description |
The coastal cod is an important commercial and recreational resource for the local communities in the Skagerrak. The situation of this and neighbouring stocks has worsened for decades, promoting an imperative need for better knowledge of the fine-scale ecology and behaviour of the species. In this study, the home ranges and vertical movement pattern of nearshore juveniles (n = 20, length = 325 mm [mean]; 265 - 375 mm [range]) were investigated using acoustic telemetry and kernel density estimators. In addition, habitat preferences were estimated by use of resource selection functions. In concordance with the hypotheses, home range sizes increased with fish length, whereas bigger fish remained at shallower depths than smaller fish. Although inconclusive, results were indicative of smaller fish displaying greater variation in vertical movement than larger fish. The fish used habitats disproportionately to what was available, and although tests were not significant the results showed a clear trend of selecting barren habitats over more complex habitat structures. These behavioural patterns are thought to reflect a dynamic decision-making process where intra- and inter-specific competition and predation pressure drive the selection of the trade-off between shelter and forage. Further, these results show that the classification of important habitats for a commercially exploited species is a complex process that should be investigated on a broader scale. |
author2 |
Nils Christian Stenseth, Esben Moland Olsen, Sigurd Heiberg Espeland |
format |
Master Thesis |
author |
Thoresen, Adine Guldborg |
author_facet |
Thoresen, Adine Guldborg |
author_sort |
Thoresen, Adine Guldborg |
title |
Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak : Effects of body size on short-term movement patterns in nearshore habitats |
title_short |
Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak : Effects of body size on short-term movement patterns in nearshore habitats |
title_full |
Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak : Effects of body size on short-term movement patterns in nearshore habitats |
title_fullStr |
Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak : Effects of body size on short-term movement patterns in nearshore habitats |
title_full_unstemmed |
Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak : Effects of body size on short-term movement patterns in nearshore habitats |
title_sort |
acoustic tracking of juvenile cod (gadus morhua) in skagerrak : effects of body size on short-term movement patterns in nearshore habitats |
publishDate |
2008 |
url |
http://hdl.handle.net/10852/11738 http://urn.nb.no/URN:NBN:no-19260 |
genre |
Gadus morhua |
genre_facet |
Gadus morhua |
op_relation |
http://urn.nb.no/URN:NBN:no-19260 Thoresen, Adine Guldborg. Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak. Masteroppgave, University of Oslo, 2008 http://hdl.handle.net/10852/11738 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Thoresen, Adine Guldborg&rft.title=Acoustic tracking of juvenile cod (Gadus morhua) in Skagerrak&rft.inst=University of Oslo&rft.date=2008&rft.degree=Masteroppgave URN:NBN:no-19260 77501 081008708 Fulltext https://www.duo.uio.no/bitstream/handle/10852/11738/2/MasterxthesisxAdinexGuldborgxThoresen.pdf |
_version_ |
1766005603772137472 |