Northwest Atlantic Mackerel (Scomber scombrus) Population Structure Evaluated using Otolith Stable Isotopes
Stock assessments for Northwest Atlantic mackerel (Scomber scombrus) assume a single stock, comprised of northern and southern contingents, each with distinct natal regions in the US and Canada. I hypothesized that otolith δ18O and δ13C values would provide discrimination between these regions based...
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ftunivmaryland:oai:drum.lib.umd.edu:1903/19545 2023-05-15T17:32:52+02:00 Northwest Atlantic Mackerel (Scomber scombrus) Population Structure Evaluated using Otolith Stable Isotopes Redding, Stephen Gray Secor, David H Digital Repository at the University of Maryland University of Maryland (College Park, Md.) Marine-Estuarine-Environmental Sciences 2017 application/pdf http://hdl.handle.net/1903/19545 https://doi.org/10.13016/M24G47 en eng doi:10.13016/M24G47 http://hdl.handle.net/1903/19545 Environmental science Ecology Biology Atlantic mackerel contingents Northwest Atlantic otolith stable isotopes population structure Thesis 2017 ftunivmaryland https://doi.org/10.13016/M24G47 2022-11-11T11:16:53Z Stock assessments for Northwest Atlantic mackerel (Scomber scombrus) assume a single stock, comprised of northern and southern contingents, each with distinct natal regions in the US and Canada. I hypothesized that otolith δ18O and δ13C values would provide discrimination between these regions based upon hydrographic differences, and such information could illuminate seasonal migrations and contingent structure. Otoliths from regions throughout the North Atlantic Ocean were carefully milled to extract carbonates corresponding to the first year of life. Significant differences occurred in otolith isotope composition across the Atlantic basin, and within the Northwest Atlantic stock, despite annual variability. In the Northwest Atlantic, two separate natal habitats and associated contingents were supported for juvenile mackerel, but incursions by the northern contingent into US waters occurred in older fish (age>2). These findings indicate that stock structure assumptions should be revisited in the assessment and management of Northwest Atlantic mackerel. Thesis North Atlantic Northwest Atlantic University of Maryland: Digital Repository (DRUM) Canada |
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Open Polar |
collection |
University of Maryland: Digital Repository (DRUM) |
op_collection_id |
ftunivmaryland |
language |
English |
topic |
Environmental science Ecology Biology Atlantic mackerel contingents Northwest Atlantic otolith stable isotopes population structure |
spellingShingle |
Environmental science Ecology Biology Atlantic mackerel contingents Northwest Atlantic otolith stable isotopes population structure Redding, Stephen Gray Northwest Atlantic Mackerel (Scomber scombrus) Population Structure Evaluated using Otolith Stable Isotopes |
topic_facet |
Environmental science Ecology Biology Atlantic mackerel contingents Northwest Atlantic otolith stable isotopes population structure |
description |
Stock assessments for Northwest Atlantic mackerel (Scomber scombrus) assume a single stock, comprised of northern and southern contingents, each with distinct natal regions in the US and Canada. I hypothesized that otolith δ18O and δ13C values would provide discrimination between these regions based upon hydrographic differences, and such information could illuminate seasonal migrations and contingent structure. Otoliths from regions throughout the North Atlantic Ocean were carefully milled to extract carbonates corresponding to the first year of life. Significant differences occurred in otolith isotope composition across the Atlantic basin, and within the Northwest Atlantic stock, despite annual variability. In the Northwest Atlantic, two separate natal habitats and associated contingents were supported for juvenile mackerel, but incursions by the northern contingent into US waters occurred in older fish (age>2). These findings indicate that stock structure assumptions should be revisited in the assessment and management of Northwest Atlantic mackerel. |
author2 |
Secor, David H Digital Repository at the University of Maryland University of Maryland (College Park, Md.) Marine-Estuarine-Environmental Sciences |
format |
Thesis |
author |
Redding, Stephen Gray |
author_facet |
Redding, Stephen Gray |
author_sort |
Redding, Stephen Gray |
title |
Northwest Atlantic Mackerel (Scomber scombrus) Population Structure Evaluated using Otolith Stable Isotopes |
title_short |
Northwest Atlantic Mackerel (Scomber scombrus) Population Structure Evaluated using Otolith Stable Isotopes |
title_full |
Northwest Atlantic Mackerel (Scomber scombrus) Population Structure Evaluated using Otolith Stable Isotopes |
title_fullStr |
Northwest Atlantic Mackerel (Scomber scombrus) Population Structure Evaluated using Otolith Stable Isotopes |
title_full_unstemmed |
Northwest Atlantic Mackerel (Scomber scombrus) Population Structure Evaluated using Otolith Stable Isotopes |
title_sort |
northwest atlantic mackerel (scomber scombrus) population structure evaluated using otolith stable isotopes |
publishDate |
2017 |
url |
http://hdl.handle.net/1903/19545 https://doi.org/10.13016/M24G47 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
North Atlantic Northwest Atlantic |
genre_facet |
North Atlantic Northwest Atlantic |
op_relation |
doi:10.13016/M24G47 http://hdl.handle.net/1903/19545 |
op_doi |
https://doi.org/10.13016/M24G47 |
_version_ |
1766131174804029440 |