Are Vertical Behaviour Patterns Related to the Pantophysin Locus in the Atlantic Cod (Gadus morhua L.)?

Abstract

Throughout their geographic distribution, marine 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 individuals carrying the Pan I AA genotype are likely to display a shallow water feeding migrations while individuals carrying 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 further 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 behavioural types described.

Temporal trends in probabilistic maturation reaction norms and growth of Atlantic cod (Gadus morhua) on the Icelandic shelf

“…Phenotypic (Marteinsdóttir and Begg 2002;Jónsdóttir et al 2006;Pardoe et al 2008), and more recently genetic (Pampoulie et al 2006) and behavioural (Pálsson and Thorsteinsson 2003;Pampoulie et al 2008;V. Thorsteinsson, MRI, Skúlagata 4, 121 Reykjavik, Iceland, unpublished data), structure within the Icelandic cod stock has been detected.…”

Evidence from data storage tags for the presence of lunar and semi-lunar behavioral cycles in spawning Atlantic cod

“…Two distinctive behavioral ecotypes occur within each geographic component. Coastal cod tend to remain in the relatively shallow water of the continental shelf, while frontal cod move to deeper waters along the shelf break and exhibit large daily vertical migrations (Pálsson and Thorsteinsson 2003;Pampoulie et al 2008;Grabowski et al 2011). These stock components exhibit differences in their reproductive phenologies (Grabowski et al 2011) and thus it is possible that their reproductive behavior has responded differently to environmental cycles.…”

Evolutionary history and adaptive significance of the polymorphic Pan I in migratory and stationary populations of Atlantic cod (Gadus morhua)

“…Further, patterns of interchromosomal linkage disequilibrium were recently found among the clinal loci distributed across three linkage groups (LG2, 7, 12) (Bradbury et al, 2014), that seem to be independent of the genomic differences between migratory and stationary populations involving the Pan I-containing LG1 (Pampoulie et al, 2008;Hemmer-Hansen et al, 2013;Karlsen et al, 2013;Therkildsen et al, 2013). In waters where NEAC and NCC juveniles co-occur, such as Varangerfjord, the two groups intermingle in their pelagic phase and so influence the allele frequencies in the pelagic samples.…”

“…The highly polymorphic marker has been widely used to characterize the genetic diversity of Atlantic cod populations and the association with growth properties (Imsland and Jónsdóttir, 2003;Nordeide et al, 2011), but the physiological function of the protein and the allelic variants still remains unknown. Atlantic cod is divided into multiple populations widely distributed in Arctic and temperate waters across the North Atlantic Ocean, including the Barents Sea and the brackish Baltic Sea, from the shoreline down to the continental shelf at depths down to 600 m. The Pan I polymorphism has been associated with different spawning and feeding behaviors in Canadian and Icelandic cod populations (Jónsdóttir et al, 1999;Pampoulie et al, 2008;Tamdrari et al, 2012;Thorsteinsson et al, 2012), but the genetic divergence is much more pronounced in offshore migratory and coastal stationary populations in the Northeast Atlantic Ocean. The large population of migratory Northeast Arctic cod (NEAC) is predominated by the Pan I BB genotype, while Pan I AA is mainly found in the relative stationary Norwegian coastal cod (NCC) living in shallow waters and fjords (Fevolden and Pogson, 1997;Pogson and Fevolden, 2003;Sarvas and Fevolden, 2005).…”