Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023
Höfundar / Authors: 1. Michelle Valliant, 2. Snæbjörn Pálsson, 1. Anja Nickel, 1. Guðbjörg Ásta Ólafsdóttir
Starfsvettvangur / Affiliations: 1. Research Centre of the Westfjords University of Iceland, 2. University of Iceland
Kynnir / Presenter: Michelle Valliant
In a changing world it is important to consider intraspecific phenotypic variation in both management and conservation. For Atlantic cod specifically, variation in migration and movement is widely documented between populations and individuals. Maintaining migratory variation in Atlantic cod is therefore critical for stock management. Icelandic Atlantic cod is generally thought to consist of a large migratory component, offshore or frontal cod, and smaller inshore or resident components. These migratory ecotypes are known to differ in many ecologically important genes and inhabit distinct environments, i.e. temperature and depth regimes, as adults. Less attention has been given to the early development of cod migratory ecotypes. In species with partial migration, that is, when part of the population migrates as others remain resident, the “decision” to migrate often depends on interactions of numerous intrinsic and extrinsic factors. To understand the plasticity or permanence of the Atlantic cod ecotypes it is therefore important to examine the ecotypes during the juvenile phase. Factors of interest include habitat selection before the onset of migration and environmental preferences or avoidance that may trigger movement. Here the results of genetic analysis, behavioral analysis and acoustic telemetry movement analysis of juvenile Atlantic cod in Icelandic nearshore waters are presented. The implication of the results for conservation and management are discussed.