Incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the Bering Sea pollock ( Gadus chalcogrammus )
Abstract Environmental conditions can create spatial and temporal variability in growth and distribution processes, yet contemporary stock assessment methods often do not explicitly address the consequences of these patterns. For example, stock assessments often assume that body weight-at-age (i.e....
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Oxford University Press (OUP)
2023
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Online Access: | http://dx.doi.org/10.1093/icesjms/fsac236 https://academic.oup.com/icesjms/article-pdf/80/2/258/49520492/fsac236.pdf |
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croxfordunivpr:10.1093/icesjms/fsac236 2024-01-07T09:42:27+01:00 Incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the Bering Sea pollock ( Gadus chalcogrammus ) Indivero, Julia Essington, Timothy E Ianelli, James N Thorson, James T Woods, Pamela Cooperative Institute for Climate, Ocean, & Ecosystem Studies National Pacific Research Board 2023 http://dx.doi.org/10.1093/icesjms/fsac236 https://academic.oup.com/icesjms/article-pdf/80/2/258/49520492/fsac236.pdf en eng Oxford University Press (OUP) https://creativecommons.org/licenses/by/4.0/ ICES Journal of Marine Science volume 80, issue 2, page 258-271 ISSN 1054-3139 1095-9289 Ecology Aquatic Science Ecology, Evolution, Behavior and Systematics Oceanography journal-article 2023 croxfordunivpr https://doi.org/10.1093/icesjms/fsac236 2023-12-08T09:35:24Z Abstract Environmental conditions can create spatial and temporal variability in growth and distribution processes, yet contemporary stock assessment methods often do not explicitly address the consequences of these patterns. For example, stock assessments often assume that body weight-at-age (i.e. size) is constant across the stocks’ range, and may thereby miss important spatio-temporal patterns. This is becoming increasingly relevant given climate-driven distributional shifts, because samples for estimating size-at-age can be spatially unbalanced and lead to biases when extrapolating into unsampled areas. Here, we jointly analysed data on the local abundance and size of walleye pollock (Gadus chalcogrammus) in the Bering Sea, to demonstrate a tractable first step in expanding spatially unbalanced size-at-age samples, while incorporating fine-scale spatial and temporal variation for inclusion in stock assessments. The data come from NOAA’s bottom trawl survey data and were evaluated using a multivariate spatio-temporal statistical model. We found extensive variation in size-at-age at fine spatial scales, though specific patterns differed between age classes. In addition to persistent spatial patterns, we also documented year-to-year differences in the spatial patterning of size-at-age. Intra-annual variation in the population-level size-at-age (used to generate the size-at-age matrix in the stock assessment) was largely driven by localized changes in fish size, while shifts in species distribution had a smaller effect. The spatio-temporal size-at-age matrix led to marginal improvement in the stock assessment fit to the survey biomass index. Results from our case study suggest that accounting for spatially unbalanced sampling improved stock assessment consistency. Additionally, it improved our understanding on the dynamics of how local and population-level demographic processes interact. As climate change affects fish distribution and growth, integrating spatiotemporally explicit size-at-age processes with ... Article in Journal/Newspaper Bering Sea Oxford University Press (via Crossref) Bering Sea ICES Journal of Marine Science 80 2 258 271 |
institution |
Open Polar |
collection |
Oxford University Press (via Crossref) |
op_collection_id |
croxfordunivpr |
language |
English |
topic |
Ecology Aquatic Science Ecology, Evolution, Behavior and Systematics Oceanography |
spellingShingle |
Ecology Aquatic Science Ecology, Evolution, Behavior and Systematics Oceanography Indivero, Julia Essington, Timothy E Ianelli, James N Thorson, James T Incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the Bering Sea pollock ( Gadus chalcogrammus ) |
topic_facet |
Ecology Aquatic Science Ecology, Evolution, Behavior and Systematics Oceanography |
description |
Abstract Environmental conditions can create spatial and temporal variability in growth and distribution processes, yet contemporary stock assessment methods often do not explicitly address the consequences of these patterns. For example, stock assessments often assume that body weight-at-age (i.e. size) is constant across the stocks’ range, and may thereby miss important spatio-temporal patterns. This is becoming increasingly relevant given climate-driven distributional shifts, because samples for estimating size-at-age can be spatially unbalanced and lead to biases when extrapolating into unsampled areas. Here, we jointly analysed data on the local abundance and size of walleye pollock (Gadus chalcogrammus) in the Bering Sea, to demonstrate a tractable first step in expanding spatially unbalanced size-at-age samples, while incorporating fine-scale spatial and temporal variation for inclusion in stock assessments. The data come from NOAA’s bottom trawl survey data and were evaluated using a multivariate spatio-temporal statistical model. We found extensive variation in size-at-age at fine spatial scales, though specific patterns differed between age classes. In addition to persistent spatial patterns, we also documented year-to-year differences in the spatial patterning of size-at-age. Intra-annual variation in the population-level size-at-age (used to generate the size-at-age matrix in the stock assessment) was largely driven by localized changes in fish size, while shifts in species distribution had a smaller effect. The spatio-temporal size-at-age matrix led to marginal improvement in the stock assessment fit to the survey biomass index. Results from our case study suggest that accounting for spatially unbalanced sampling improved stock assessment consistency. Additionally, it improved our understanding on the dynamics of how local and population-level demographic processes interact. As climate change affects fish distribution and growth, integrating spatiotemporally explicit size-at-age processes with ... |
author2 |
Woods, Pamela Cooperative Institute for Climate, Ocean, & Ecosystem Studies National Pacific Research Board |
format |
Article in Journal/Newspaper |
author |
Indivero, Julia Essington, Timothy E Ianelli, James N Thorson, James T |
author_facet |
Indivero, Julia Essington, Timothy E Ianelli, James N Thorson, James T |
author_sort |
Indivero, Julia |
title |
Incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the Bering Sea pollock ( Gadus chalcogrammus ) |
title_short |
Incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the Bering Sea pollock ( Gadus chalcogrammus ) |
title_full |
Incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the Bering Sea pollock ( Gadus chalcogrammus ) |
title_fullStr |
Incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the Bering Sea pollock ( Gadus chalcogrammus ) |
title_full_unstemmed |
Incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the Bering Sea pollock ( Gadus chalcogrammus ) |
title_sort |
incorporating distribution shifts and spatio-temporal variation when estimating weight-at-age for stock assessments: a case study involving the bering sea pollock ( gadus chalcogrammus ) |
publisher |
Oxford University Press (OUP) |
publishDate |
2023 |
url |
http://dx.doi.org/10.1093/icesjms/fsac236 https://academic.oup.com/icesjms/article-pdf/80/2/258/49520492/fsac236.pdf |
geographic |
Bering Sea |
geographic_facet |
Bering Sea |
genre |
Bering Sea |
genre_facet |
Bering Sea |
op_source |
ICES Journal of Marine Science volume 80, issue 2, page 258-271 ISSN 1054-3139 1095-9289 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1093/icesjms/fsac236 |
container_title |
ICES Journal of Marine Science |
container_volume |
80 |
container_issue |
2 |
container_start_page |
258 |
op_container_end_page |
271 |
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1787423423714033664 |