Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023

Otolith Shape Analysis for Stock Identification of Blue Whiting (Micromesistius poutassou) in the Northeast Atlantic

Höfundar / Authors: Svandís Eva Aradóttir (1,2), Haseeb Randhawa (2), Anna Heiða Ólafsdóttir (1)

Starfsvettvangur / Affiliations: 1. Marine and Freshwater Research Institute, 2. University of Iceland

Kynnir / Presenter: Svandís Eva Aradóttir

Understanding the stock structure and spatio-temporal distribution of fish populations are vital for sustainable fisheries management. Most stock assessment models are designed to be applied to single stocks. Violation of this assumption and neglecting to discriminate between different stocks can lead to the overfishing of regional stocks, erosion of genetic diversity, and reduction in ecosystem services. Spawning stock biomass of blue whiting (Micromesistius poutassou) is estimated as single stock by International Council for the Exploration of the Sea (ICES), and managed as one. However, various research using different methods, such as allozymes, micro-satellites, and otolith shape analyses, suggest that there is more than one stock of blue whiting in the Northeast Atlantic. This study is part of a larger project using an integrative approach to assess the stock structure of blue whiting across the Northeast Atlantic. Here, we focus on the use of otolith shape analysis as a tool for stock identification of blue whiting, using historical otolith samples collected from catch samples from the Icelandic pelagic fishing fleet during the period of 1999 to 2020. The aim of the study is to see if otolith shape analysis is an acceptable component for stock identification of blue whiting and determine whether there are more than one blue whiting spawning stocks being targeted by the Icelandic pelagic fleet.