Initial Genetic Evidence of Population Structure of Greenland Halibut (Reinhardtius hippoglossoides) in the Northwest Atlantic

Greenland halibut (Reinhardtius hippoglossoides) supports one of the major groundfish fisheries of the Northwest Atlantic and its biological stock structure is an important management concern. Using nuclear DNA microsatellite markers and a combination of summary statistics and Bayesian inference, we identified two distinct stocks, both represented within the Baffin Island–West Greenland complex and in the Gulf of St. Lawrence. While a North-South pattern of genetic structure was not supported, our data suggest East-West differentiation within Baffin Bay and Davis Strait. Genetic distances between samples were not correlated with geographic distances, and some degree of intermingling of the two stocks within the same assemblages was detected. Our preliminary results warrant further investigation of the observed patterns with the support of an intensive sampling scheme.