Abstract

RAPD analysis was performed on 258 minke whales: 201 individuals from the North Atlantic (NA) and 57 from the Western North Pacific (WNP). Nine 10-mer primers generated 20 RAPD-markers. Of these, two were present only in individuals from the WNP and one was present only in individuals from the NA. Six other markers showed a 50% or higher difference in frequency between the two oceans. The matrix of absence/presence of the markers was submitted to principal component analysis (PCA) and to analysis of the molecular variance (AMOVA). The first factor of the PCA clearly separated the minke whales from the NA from those of the WNP, but minks whales captured in different small areas of the NA (Northeastern: EN, North Sea; EC, Lofoten-Vesteralen; EB, Finnmark and Barents Sea; ES, Bear Island and Svalbard; and Central: CM, Jan Mayen), and in the WNP (7, 8, 11) did not form separate clusters. AMOVA of the data allocated over 63% (p0.0001) of the total genetic variability of the model to differences between the NA and the WNP, and over 36% to within ocean individual differences. Two percent (p0.00001) of the genetic variability in the NA could be attributed to differences between two groups: individuals from EN, EC, and EB (1996) and those from CM (1996) and ES (1996 and 1994), while minke whales from EC and EB captured in 1994 were indistinguishable from any of the other two groups. There were no significant differences among the three areas of capture in the WNP. The present results corroborate the presence of two different populations of minke whale, that is in the NA and in the WNP, and indicate that there may be two closely related breeding stocks in the NA waters. (C) 1999 International Council for the Exploration of the Sea.