Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish
Background: Ecological traps form when artificial structures are added to natural habitats and induce mismatches between habitat preferences and fitness consequences. Their existence in terrestrial systems has been documented, yet little evidence suggests they occur in marine environments. Coastal f...
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Online Access: | http://hdl.handle.net/11250/2507053 https://doi.org/10.1371/journal.pone.0015646 |
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ftnofima:oai:nofima.brage.unit.no:11250/2507053 2023-05-15T15:27:45+02:00 Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish Dempster, Timothy David Sánchez-Jerez, Pablo Fernandez-Jover, Damian Bayle-Sempere, Just Nilsen, Rune Bjørn, Pål Arne Uglem, Ingebrigt 2011 application/pdf http://hdl.handle.net/11250/2507053 https://doi.org/10.1371/journal.pone.0015646 eng eng urn:issn:1932-6203 http://hdl.handle.net/11250/2507053 https://doi.org/10.1371/journal.pone.0015646 cristin:861972 6 PLoS ONE 1 Peer reviewed Journal article 2011 ftnofima https://doi.org/10.1371/journal.pone.0015646 2022-11-18T06:51:12Z Background: Ecological traps form when artificial structures are added to natural habitats and induce mismatches between habitat preferences and fitness consequences. Their existence in terrestrial systems has been documented, yet little evidence suggests they occur in marine environments. Coastal fish farms are widespread artificial structures in coastal ecosystems and are highly attractive to wild fish. Methodology/Principal Findings: To investigate if coastal salmon farms act as ecological traps for wild Atlantic cod (Gadus morhua) and saithe (Pollachius virens), we compared proxy measures of fitness between farm-associated fish and control fish caught distant from farms in nine locations throughout coastal Norway, the largest coastal fish farming industry in the world. Farms modified wild fish diets in both quality and quantity, thereby providing farm-associated wild fish with a strong trophic subsidy. This translated to greater somatic (saithe: 1.06-1.12 times; cod: 1.06-1.11 times) and liver condition indices (saithe: 1.4-1.8 times; cod: 2.0-2.8 times) than control fish caught distant from farms. Parasite loads of farm-associated wild fish were modified from control fish, with increased external and decreased internal parasites, however the strong effect of the trophic subsidy overrode any effects of altered loads upon condition. Conclusions and Significance: Proxy measures of fitness provided no evidence that salmon farms function as ecological traps for wild fish. We suggest fish farms may act as population sources for wild fish, provided they are protected from fishing while resident at farms to allow their increased condition to manifest as greater reproductive output. Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish publishedVersion Article in Journal/Newspaper atlantic cod Gadus morhua Nofima Knowledge Archive (Brage) Norway PLoS ONE 6 1 e15646 |
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Nofima Knowledge Archive (Brage) |
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ftnofima |
language |
English |
description |
Background: Ecological traps form when artificial structures are added to natural habitats and induce mismatches between habitat preferences and fitness consequences. Their existence in terrestrial systems has been documented, yet little evidence suggests they occur in marine environments. Coastal fish farms are widespread artificial structures in coastal ecosystems and are highly attractive to wild fish. Methodology/Principal Findings: To investigate if coastal salmon farms act as ecological traps for wild Atlantic cod (Gadus morhua) and saithe (Pollachius virens), we compared proxy measures of fitness between farm-associated fish and control fish caught distant from farms in nine locations throughout coastal Norway, the largest coastal fish farming industry in the world. Farms modified wild fish diets in both quality and quantity, thereby providing farm-associated wild fish with a strong trophic subsidy. This translated to greater somatic (saithe: 1.06-1.12 times; cod: 1.06-1.11 times) and liver condition indices (saithe: 1.4-1.8 times; cod: 2.0-2.8 times) than control fish caught distant from farms. Parasite loads of farm-associated wild fish were modified from control fish, with increased external and decreased internal parasites, however the strong effect of the trophic subsidy overrode any effects of altered loads upon condition. Conclusions and Significance: Proxy measures of fitness provided no evidence that salmon farms function as ecological traps for wild fish. We suggest fish farms may act as population sources for wild fish, provided they are protected from fishing while resident at farms to allow their increased condition to manifest as greater reproductive output. Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish publishedVersion |
format |
Article in Journal/Newspaper |
author |
Dempster, Timothy David Sánchez-Jerez, Pablo Fernandez-Jover, Damian Bayle-Sempere, Just Nilsen, Rune Bjørn, Pål Arne Uglem, Ingebrigt |
spellingShingle |
Dempster, Timothy David Sánchez-Jerez, Pablo Fernandez-Jover, Damian Bayle-Sempere, Just Nilsen, Rune Bjørn, Pål Arne Uglem, Ingebrigt Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish |
author_facet |
Dempster, Timothy David Sánchez-Jerez, Pablo Fernandez-Jover, Damian Bayle-Sempere, Just Nilsen, Rune Bjørn, Pål Arne Uglem, Ingebrigt |
author_sort |
Dempster, Timothy David |
title |
Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish |
title_short |
Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish |
title_full |
Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish |
title_fullStr |
Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish |
title_full_unstemmed |
Proxy Measures of Fitness Suggest Coastal Fish Farms Can Act as Population Sources and Not Ecological Traps for Wild Gadoid Fish |
title_sort |
proxy measures of fitness suggest coastal fish farms can act as population sources and not ecological traps for wild gadoid fish |
publishDate |
2011 |
url |
http://hdl.handle.net/11250/2507053 https://doi.org/10.1371/journal.pone.0015646 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
atlantic cod Gadus morhua |
genre_facet |
atlantic cod Gadus morhua |
op_source |
6 PLoS ONE 1 |
op_relation |
urn:issn:1932-6203 http://hdl.handle.net/11250/2507053 https://doi.org/10.1371/journal.pone.0015646 cristin:861972 |
op_doi |
https://doi.org/10.1371/journal.pone.0015646 |
container_title |
PLoS ONE |
container_volume |
6 |
container_issue |
1 |
container_start_page |
e15646 |
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1766358171038777344 |