Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland
Predation risk is a driving force in the distribution of juvenile fish. In coastal Newfoundland, age-0 Atlantic cod (Gadus morhua) use the protective cover of eelgrass (Zostera marina) in preference to exposed, sandy areas. Studies suggest that habitat configuration is closely correlated to the popu...
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Memorial University of Newfoundland
2004
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ftmemorialuniv:oai:research.library.mun.ca:10562 2023-10-01T03:54:31+02:00 Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland Gorman, Ann Marie 2004 application/pdf https://research.library.mun.ca/10562/ https://research.library.mun.ca/10562/1/Gorman_AnnMarie.pdf en eng Memorial University of Newfoundland https://research.library.mun.ca/10562/1/Gorman_AnnMarie.pdf Gorman, Ann Marie <https://research.library.mun.ca/view/creator_az/Gorman=3AAnn_Marie=3A=3A.html> (2004) Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland. Masters thesis, Memorial University of Newfoundland. thesis_license Thesis NonPeerReviewed 2004 ftmemorialuniv 2023-09-03T06:47:55Z Predation risk is a driving force in the distribution of juvenile fish. In coastal Newfoundland, age-0 Atlantic cod (Gadus morhua) use the protective cover of eelgrass (Zostera marina) in preference to exposed, sandy areas. Studies suggest that habitat configuration is closely correlated to the population dynamics of certain species. A relationship between eelgrass patch morphology and predation risk of cod could allow for indirect assessment of natural predation based primarily on eelgrass configuration - a variable more easily quantified than natural predation itself. In three experiments, I used a tethering technique in Newman Sound, Bonavista Bay, Newfoundland, Canada, to quantify the relative predation risk of post-settled age-0 cod in natural eelgrass habitats. I examined the influence of eelgrass patch size (1-80m²) on predation risk based on the assumption that larger patch size results in lower predation compared to small patches. I also tested for the presence of edge effects at an 18 m long, vertical boundary between a mud and an eelgrass habitat. Lastly, I evaluated the effect of patch shape on predation by quantifying the fractal exponent of individual patches. I conclude that predation was correlated to patch area and proximity to patch edge, but not to the shape of individual patches. Thesis atlantic cod Bonavista Bay Gadus morhua Newfoundland Memorial University of Newfoundland: Research Repository Canada |
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Memorial University of Newfoundland: Research Repository |
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English |
description |
Predation risk is a driving force in the distribution of juvenile fish. In coastal Newfoundland, age-0 Atlantic cod (Gadus morhua) use the protective cover of eelgrass (Zostera marina) in preference to exposed, sandy areas. Studies suggest that habitat configuration is closely correlated to the population dynamics of certain species. A relationship between eelgrass patch morphology and predation risk of cod could allow for indirect assessment of natural predation based primarily on eelgrass configuration - a variable more easily quantified than natural predation itself. In three experiments, I used a tethering technique in Newman Sound, Bonavista Bay, Newfoundland, Canada, to quantify the relative predation risk of post-settled age-0 cod in natural eelgrass habitats. I examined the influence of eelgrass patch size (1-80m²) on predation risk based on the assumption that larger patch size results in lower predation compared to small patches. I also tested for the presence of edge effects at an 18 m long, vertical boundary between a mud and an eelgrass habitat. Lastly, I evaluated the effect of patch shape on predation by quantifying the fractal exponent of individual patches. I conclude that predation was correlated to patch area and proximity to patch edge, but not to the shape of individual patches. |
format |
Thesis |
author |
Gorman, Ann Marie |
spellingShingle |
Gorman, Ann Marie Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland |
author_facet |
Gorman, Ann Marie |
author_sort |
Gorman, Ann Marie |
title |
Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland |
title_short |
Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland |
title_full |
Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland |
title_fullStr |
Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland |
title_full_unstemmed |
Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland |
title_sort |
predation-risk in juvenile atlantic cod with respect to eelgrass patch characteristics in newman sound, bonavista bay, newfoundland |
publisher |
Memorial University of Newfoundland |
publishDate |
2004 |
url |
https://research.library.mun.ca/10562/ https://research.library.mun.ca/10562/1/Gorman_AnnMarie.pdf |
geographic |
Canada |
geographic_facet |
Canada |
genre |
atlantic cod Bonavista Bay Gadus morhua Newfoundland |
genre_facet |
atlantic cod Bonavista Bay Gadus morhua Newfoundland |
op_relation |
https://research.library.mun.ca/10562/1/Gorman_AnnMarie.pdf Gorman, Ann Marie <https://research.library.mun.ca/view/creator_az/Gorman=3AAnn_Marie=3A=3A.html> (2004) Predation-risk in juvenile Atlantic cod with respect to eelgrass patch characteristics in Newman Sound, Bonavista Bay, Newfoundland. Masters thesis, Memorial University of Newfoundland. |
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thesis_license |
_version_ |
1778522279539376128 |