Farming of Atlantic cod Gadus morhua in the vicinity of major spawning sites for Norwegian coastal cod populations - is it hazardous?

Waters along and adjacent to the coast of northern Norway are unique in housing two major populations of Atlantic cod with very di erent life histories. The Northeast Arctic cod (NEAC) has its nursery and feeding grounds in the Barents Sea but migrates to the coast of northern Norway to spawn. Norwegian coastal cod (NCC) is more stationary, spawns mainly at local sites in individual ords but to some degree also overlap with the spawning sites of NEAC (Fig.1). These distinctive patterns in life history are re ected in a clear-cut genetic divergence between the two populations. Various molecular genetic markers (scnDNA, microsatellites and SNPs) have displayed genetic di erences between NEAC and NCC which are remarkable for marine sh with a comparable gene ow potential (cf. Sarvas and Fevolden 2005, Wennevik et al. 2008, and Westgaard and Fevolden 2008 for recent updates)