Genetic Phylogeography of Greenland halibut (Reinhardtius hippoglossoides)
(M. L. Vis,S. M. Carr, R. Bowering, & W. S. Davidson. 1997. "Can. J. Fish. Aquat. Sci." 54:1812)
     In consequence of its change in status from an "underutilized species" to a major groundfish fishery in the western Atlantic, Greenland halibut  (Reinhardtius hippoglossoides) have received a high public profile, including a short-lived "Turbot War" between Canada and the European Union during 1995.  Previous data suggest that Greenland halibut comprise a single self-sustaining stock from Davis Strait to the Grand Bank and Flemish Cap.  Fish in the Gulf of St. Lawrence are believed to be a separate, relatively small self-sustaining stock, which receives migrants from the Labrador area through the Strait of Belle Isle between Quebec and the island of Newfoundland.  The major spawning location in the western Atlantic is in the deep slope area of Davis Strait along the boundary between Canada and Greenland.

    A maximum parsimony network of 22 mtDNA genotypes is shown: a single nucleotide substitution occurs along each network branch. Genotypes A, B, and C occur at moderate frequencies in all seven samples . The remaining genotypes occur at smaller frequencies in the populations as indicated. Genetic distances among populations are unrelated to their geographic distribution. Halibut in the Gulf of St. Lawrence are genetically distinctive: the relative frequences of A & B in this sample are reversed with respect to other populations. Otherwise samples from opposite sides of the Atlantic are typically more similar than are geographically contiguous samples from the Northwest Atlantic. [UPGMA (left) and Neighbor-Joining analysis (right) of Rogers' distances]

Figue &  text material © 2004 by Steven M. Carr: not to be reproduced without permission