ORIGINAL PAPER Are Vertical Behaviour Patterns Related to the Pantophysin Locus in the Atlantic Cod (Gadus morhua L.)? Christophe Pampoulie Æ Klara B. Jakobsdo ´ttir Æ Guðru ´ n Marteinsdo ´ttir Æ Vilhja ´lmur Thorsteinsson Received: 8 May 2007 / Accepted: 11 October 2007 / Published online: 3 November 2007 Ó Springer Science+Business Media, LLC 2007 Abstract Throughout their geographic distribution, mar- ine fish species often form subpopulations with limited connectivity, among which individuals display a variety of migratory behaviours. Fish behaviour experiments using Data Storage Tags (DSTs) have been useful to define the natural movement of individuals. In Icelandic waters, such experiments have indicated the presence of two distinct behaviour types of the Atlantic cod Gadus morhua, related to vertical migrations and habitat choice in feeding migrations. Some individuals have been shown to stay most of the time in shallow waters characterised by the seasonal trend in temperature for the shelf waters, while other migrate to deeper and colder waters where most of them forage in temperature fronts characterized by highly variable temperatures. The analysis of the pantophysin locus (Pan I) of the same individuals revealed that indi- viduals carrying the Pan I AA genotype are likely to display a shallow water feeding migrations while individuals car- rying the Pan I BB genotype preferred deeper waters and forage near thermal fronts. The heterozygote exhibited both type of behaviours. This study therefore suggests that fur- ther research need to be done on the pantophysin locus and its potential effects on cod phenotypes to assess the potential relationship between this locus and the behav- ioural types described. Keywords Cod Á Gadus morhua Á Tagging experiments Á DST Á Pan I locus Á Behaviour Á Vertical migration Introduction Despite the importance for fishery management, information on movement and behaviour of individuals of different stock components is often limited. Even more so, the intercon- nection between the genetic set-up of stocks and resulting behavioural adaptations is completely lacking. The Atlantic cod Gadus morhua L. is widely distributed throughout the continental shelf on both sides of the North Atlantic Ocean. Within its range, cod stocks have been characterised through a combination of techniques such as genetics, morphometric analyses and conventional tag-recapture programs (see Pampoulie et al. 2006; Marcil et al. 2006; Robichaud and Rose 2004 for a review). The application of neutral and non- neutral genetic markers and conventional tagging studies has shown that cod populations are not evenly distributed and do often form a web of subpopulations with different levels of connectivity. The application of data storage tags (DSTs) to fisheries science has been shown to be a powerful way to study the natural movement of individuals (Arnold and Dewar 2000; Thorsteinsson 2002; Neat et al. 2006). DSTs can be directly attached to the fish or inserted in the abdominal cavity where they record environmental param- eters such as depth and ambient temperature over extensive periods of time. Such recording of both horizontal and vertical movements can provide information on the behav- ioural processes responsible for residential or migratory behavioural types of Atlantic cod. Edited by Stephen Maxson. Electronic supplementary material The online version of this article (doi:10.1007/s10519-007-9175-y) contains supplementary material, which is available to authorized users. C. Pampoulie (&) Á K. B. Jakobsdo ´ttir Á V. Thorsteinsson Marine Research Institute, Sku ´lagata 4, 101 Reykjavik, Iceland e-mail: chrisp@hafro.is G. Marteinsdo ´ttir Department of Biology, University of Iceland, Sturlugata 7, 101 Reykjavik, Iceland 123 Behav Genet (2008) 38:76–81 DOI 10.1007/s10519-007-9175-y