Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023
Höfundar / Authors: Brendon Lee (1), Haseeb S Randhawa (1), Anna H Ólafsdóttir (2)
Starfsvettvangur / Affiliations: 1. Faculty of Life and Environmental Sciences, University of Iceland, Sturlugata 7, 102 Reykjavik, Iceland; 2. Marine and Freshwater Research Institute, Fornubúðum 5, IS-220 Hafnarfírði
Kynnir / Presenter: Brendon Lee
Understanding fish population structure is vital for ensuring sustainable exploitation and ecosystem health. Blue whiting (Micromesistius poutassou) is an ecologically and economically significant mesopelagic species, predominantly found along the continental shelf edge across the Northeast (NE) Atlantic. Historically, blue whiting (1981 - 1992) was managed as two stocks, consisting of northern and southern contingents separated along a conditional line at 48°N through the main spawning area. However, since 1993, it has been managed as a single stock. Despite extensive research, ongoing debate surrounds the question of whether a single or two-stock hypothesis better characterizes the population structure. Here we present an interdisciplinary review of available literature investigating blue whiting population structure in NE Atlantic waters. Our review suggests that spawning location may define recruitment into northern and southern contingents, affecting subsequent migratory patterns and individual affiliation. However, annual environmental conditions affecting spawning areas obscure the distinction between contingents, impacting spatial patterns in cohort strength. To address these complexities and reduce uncertainties, further interdisciplinary research is needed, particularly in the context of climate change. Otolith chemical analysis shows promise for delineating biological stocks and inform sustainable management practices that can account for intrapopulation diversity.