{"id":25345,"date":"2023-12-22T13:26:33","date_gmt":"2023-12-22T12:26:33","guid":{"rendered":"https:\/\/nr.stage.dekodes.no\/en\/?post_type=bc_project&#038;p=25345"},"modified":"2025-01-03T10:34:00","modified_gmt":"2025-01-03T09:34:00","slug":"fish-stock-assessment-and-harvest-quota","status":"publish","type":"bc_project","link":"https:\/\/nr.stage.dekodes.no\/en\/projects\/fish-stock-assessment-and-harvest-quota\/","title":{"rendered":"Fish stock assessment and harvest quota"},"content":{"rendered":"\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-28f84493 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:66.66%\">\n<p class=\"has-sizing-large\"><strong>We develop methods for assessing stocks and setting harvest quotas for fish and marine mammals, promoting sustainable use of marine resources. <\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/nr.stage.dekodes.no\/content\/uploads\/sites\/2\/2023\/12\/Fish_farming_on_Astafjorden_in_Gratangen_Troms_og_Finnmark_Norway_2022_June-1024x683.jpg\" alt=\"The image shows a fish farm in Northern Norway and a boat passing by. In the background a mountainous coastline is visible.\" class=\"wp-image-25354\" style=\"width:800px\" srcset=\"https:\/\/nr.stage.dekodes.no\/content\/uploads\/sites\/2\/2023\/12\/Fish_farming_on_Astafjorden_in_Gratangen_Troms_og_Finnmark_Norway_2022_June-1024x683.jpg 1024w, https:\/\/nr.stage.dekodes.no\/content\/uploads\/sites\/2\/2023\/12\/Fish_farming_on_Astafjorden_in_Gratangen_Troms_og_Finnmark_Norway_2022_June-300x200.jpg 300w, https:\/\/nr.stage.dekodes.no\/content\/uploads\/sites\/2\/2023\/12\/Fish_farming_on_Astafjorden_in_Gratangen_Troms_og_Finnmark_Norway_2022_June-768x512.jpg 768w, https:\/\/nr.stage.dekodes.no\/content\/uploads\/sites\/2\/2023\/12\/Fish_farming_on_Astafjorden_in_Gratangen_Troms_og_Finnmark_Norway_2022_June.jpg 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Fish farming is an important industry in Norway. Here seen in Astafjorden in Troms and Finnmark.  <\/em>Image: Ximonic \/ Wikimedia Commons. <\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Ensuring sustainable fisheries<\/strong><\/h2>\n\n\n\n<p>Knowledge of the current status of a fish stock is crucial for a sustainable fishery. Overestimation of the abundance of a fish stock can give too high quotas and thus overfishing and possibly extinction of the stock. On the other hand, unnecessarily low quotas result in poor utilisation of an important resource. <\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Population models to estimate fish abundance<\/strong><\/h2>\n\n\n\n<p>Data is collected for the most important fish stocks and marine mammals, such as seals and whales. The data includes surveys with echosounders, and trawling and sampling from commercial catches. These are then used in a population model to estimate the fish and mammal abundance within each age. <\/p>\n\n\n\n<p>We are developing new models for stock assessments and harvest quota, and enhancing previous methods. This includes modelling errors in age readings and interpretation of echosounder signals, combining age and length data and spatial modelling over an area. We are also refining the population models, specifically looking at how they are used to set fishing quotas.<\/p>\n\n\n\n<p>We also participate in international working groups organised by the International Council for the Exploration of the Sea (ICES).<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:33.33%\">\n<h3 class=\"wp-block-heading\">To learn more about this project, please contact:<\/h3>\n\n\n\t\t<div id=\"post-type-multi-block_e82d7f278809f9a8528e216cfc2bc5ca\" class=\"wp-block-post-type-multi type-manual style-card-bc_employee t2-grid\">\n\t\t\t\t\t\t\t<div class=\"t2-grid-item-col-12\">\n\t\t\t\t\t\t<a href=\"https:\/\/nr.stage.dekodes.no\/en\/employees\/magne-aldrin\/\" class='card-employee'>\n\t\t\t\t\t<figure>\n\t\t\t\t<img decoding=\"async\" src=\"https:\/\/nr.stage.dekodes.no\/content\/uploads\/sites\/2\/2024\/10\/magne-aldrin-1.jpg\" alt=\"\">\n\t\t\t<\/figure>\n\t\t\t\t<div class=\"card-employee__content\">\n\t\t\t<p class=\"card-employee__name\">Magne Aldrin<\/p>\n\t\t\t\t\t\t\t<p class=\"card-employee__position\">Research Leader<\/p>\n\t\t\t\t\t\t<svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 24 24\" height=\"24\" width=\"24\" class=\"t2-icon t2-icon-arrowforward\" aria-hidden=\"true\" focusable=\"false\"><path d=\"M15.9 4.259a1.438 1.438 0 0 1-.147.037c-.139.031-.339.201-.421.359-.084.161-.084.529-.001.685.035.066 1.361 1.416 2.947 3l2.882 2.88-10.19.02c-8.543.017-10.206.029-10.29.075-.282.155-.413.372-.413.685 0 .313.131.53.413.685.084.046 1.747.058 10.29.075l10.19.02-2.882 2.88c-1.586 1.584-2.912 2.934-2.947 3-.077.145-.085.521-.013.66a.849.849 0 0 0 .342.35c.156.082.526.081.68-.001.066-.035 1.735-1.681 3.709-3.656 2.526-2.53 3.606-3.637 3.65-3.742A.892.892 0 0 0 23.76 12a.892.892 0 0 0-.061-.271c-.044-.105-1.124-1.212-3.65-3.742-1.974-1.975-3.634-3.616-3.689-3.645-.105-.055-.392-.107-.46-.083\"\/><\/svg>\n\t\t<\/div>\n\t<\/a>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\n\n\n<div class=\"wp-block-group has-primary-200-background-color has-background\">\n<p>Project: Framework agreement on delivery of statistics and computational mathematics<\/p>\n\n\n\n<p>Funding: Institute of Marine Research (IMR)<\/p>\n\n\n\n<p>Period: 2021 &#8211; 2025<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-group\">\n<p><strong>Further reading<\/strong><\/p>\n\n\n\n<p><a href=\"10.1139\/cjfas-2022-0250.\" data-type=\"link\" data-id=\"doi:10.1139\/cjfas-2022-0250.\">Detecting significant retrospective patterns in state space fish stock <\/a><a rel=\"noreferrer noopener\" href=\"10.1139\/cjfas-2022-0250.\" data-type=\"link\" data-id=\"doi:10.1139\/cjfas-2022-0250.\" target=\"_blank\">assessment<\/a> &#8211; Canadian Science Publishing, 17.07.2023.<\/p>\n\n\n\n<p><a href=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab205.\" data-type=\"link\" data-id=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab205.\">Prediction-variance relation in a state-<\/a><a rel=\"noreferrer noopener\" href=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab205.\" data-type=\"link\" data-id=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab205.\" target=\"_blank\">space<\/a><a href=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab205.\" data-type=\"link\" data-id=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab205.\"> fish stock assessment model <\/a>&#8211; Oxford Academic, 27.10.2021.<\/p>\n\n\n\n<p><a href=\"10.1016\/j.fishres.2021.106071\">Caveats with estimating natural mortality rates in stock assessment <\/a><a rel=\"noreferrer noopener\" href=\"10.1016\/j.fishres.2021.106071\" target=\"_blank\">models<\/a><a href=\"10.1016\/j.fishres.2021.106071\"> using age aggregated catch data and abundance indices<\/a> &#8211; ScienceDirect, 24.07.2021.<\/p>\n\n\n\n<p><a href=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab073.\">Predicting abundance indices in areas without <\/a><a rel=\"noreferrer noopener\" href=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab073.\" target=\"_blank\">coverage<\/a><a href=\"https:\/\/doi.org\/10.1093\/icesjms\/fsab073.\"> with a latent spatio-temporal Gaussian model<\/a> &#8211; Oxford Academic, 14.06.2021.<\/p>\n\n\n\n<p><a href=\"10.1016\/j.fishres.2020.105585\">The specification of the data model part in the SAM model matters<\/a> &#8211; ScienceDirect, 19.05.2020.<\/p>\n\n\n\n<p><a rel=\"noreferrer noopener\" href=\"http:\/\/Jourdain, N., Breivik, O.N., Fuglebakk, E., Aanes, S., V\u00f8lstad, J.H. (2020). Evaluation of sampling strategies for age determination of cod (Gadus morhua) sampled at the North Sea International Bottom Trawl Survey. ICES Journal of Marine Science, vol. 77, pp. 859-869, doi: https:\/\/doi.org\/10.1093\/icesjms\/fsaa013.\" target=\"_blank\">Evaluation of sampling strategies for age determination of cod (Gadus morhua) sampled at the North Sea International Bottom Trawl Survey<\/a> &#8211; Oxford Academic, 29.02.2020.<\/p>\n\n\n\n<p><a rel=\"noreferrer noopener\" href=\"10.1016\/j.fishres.2018.08.001.\" target=\"_blank\">Comments on incongruous formulations in the SAM (state-space assessment model) model and consequences for fish stock assessment<\/a> &#8211; ScienceDirect, 17.08.2018.<\/p>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"featured_media":25354,"template":"","meta":{"_acf_changed":false,"_trash_the_other_posts":false,"editor_notices":[],"footnotes":""},"class_list":["post-25345","bc_project","type-bc_project","status-publish","has-post-thumbnail"],"acf":[],"_links":{"self":[{"href":"https:\/\/nr.stage.dekodes.no\/en\/wp-json\/wp\/v2\/bc_project\/25345","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nr.stage.dekodes.no\/en\/wp-json\/wp\/v2\/bc_project"}],"about":[{"href":"https:\/\/nr.stage.dekodes.no\/en\/wp-json\/wp\/v2\/types\/bc_project"}],"version-history":[{"count":5,"href":"https:\/\/nr.stage.dekodes.no\/en\/wp-json\/wp\/v2\/bc_project\/25345\/revisions"}],"predecessor-version":[{"id":33683,"href":"https:\/\/nr.stage.dekodes.no\/en\/wp-json\/wp\/v2\/bc_project\/25345\/revisions\/33683"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nr.stage.dekodes.no\/en\/wp-json\/wp\/v2\/media\/25354"}],"wp:attachment":[{"href":"https:\/\/nr.stage.dekodes.no\/en\/wp-json\/wp\/v2\/media?parent=25345"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}