Population Genomics of West Coast and Alaskan Sablefish (Anoplopoma fimbria)

The sablefish (Anoplopoma fimbria) is a wide-ranging species in the Northern Pacific Ocean.  It is the target of a multinational fishery and there has been recent interest in the commercial aquaculture of the species. It is generally accepted that two stocks of sablefish exist; a northern population that inhabits waters north of Vancouver Island, British Columbia and a southern population that is found off the West Coast of the United States down to Baja California. The delineation of these two stocks is based on growth rates, size at maturity and migration rates inferred from tagging studies. With little knowledge available on the population genetics of this species, this study uses restriction site associated DNA (RAD) sequencing to survey the sablefish genome in order to characterize sablefish population structure and identify genomic regions that may be under selective pressure. Aquaculture companies currently collect broodstock from the wild with little knowledge on the genetic diversity of the source population. With observed differences in growth rates and size at maturity between the northern and southern stocks, a better understanding of the natural genetic variation in sablefish populations and selective forces that they are subject to may help aquaculture companies identify populations with traits of interest as potential sources of broodstock. The SNPs developed here can also be used as a resource to select for traits, track parentage and maintain captive breeding programs in an aquaculture setting.