An overview of genetic relationships of Canadian and adjacent populations of belugas (&lt;i&gt;Delphinapterus leucas&lt;/i&gt;) with emphasis on Baffin Bay and Canadian eastern Arctic populations

Bge De March,L D Maiers,M K Friesen

doi:10.7557/3.2835

Abstract

Our current knowledge of the molecular genetics of High Arctic beluga (Delphinapterus leucas) populations (West Greenland, Lancaster Sound/Barrow Strait, Grise Fiord) and populations that are related (southeast Baffin, Beaufort Sea), is presented. In general, genetic analyses confirm the designation of putative stocks and suggest the existence of more stocks than previously described. Comparisons based on mitochondrial DNA haplotypes show that West Greenland (1992) belugas were significantly differentiated from Lancaster Sound/Barrow Strait, Kimmirut, Iqaluit, and/or Pangnirtung but not from Grise Fiord. Grise Fiord haplotypes were not significantly differentiated from Lancaster Sound/Barrow Strait and not from southeast Baffin locations in some years. Lancaster Sound and southeast Baffin collections were not significantly differentiated from each other. These patterns existed for most years within locations, however a few yearly collections within major locations had different patterns. The collections that differed were small groups with few haplotypes, most likely relatives. Patterns in microsatellite differentiation were slightly different than those for haplotypes. This may be due to the fact that individuals in sampled summering populations breed with individuals in other populations during migration or in overwintering areas. West Greenland and Grise Fiord microsatellites were not significantly differentiated from each other. However, Greenland differed from Lancaster Sound and southeast Baffin Island, while Grise Fiord did not. In southeast Baffin Island, Pangnirtung samples differed from Kimmirut using both haplotypes and microsatellites. Iqaluit samples had intermediate genetic characteristics between Pangnirtung and Kimmirut. Patterns of significant differentiation among collections within locations was believed to be due to a combination of temporal patterns, sampling of relatives, chance, seasonal hunting, small sample sizes, and actual differences among populations.

Highlights

The beluga (Delphinapterus leucas) is a small toothed whale that is economically and socially important to northern people
Belugas probably mate in the early spring (Cosens et al 1993), so they may or may not be mating with the same animals that congregate in their summering areas
Beluga samples The majority of the samples in the present analyses were from summer hunts and some were from scientific collections

Summary

Introduction

The beluga (Delphinapterus leucas) is a small toothed whale that is economically and socially important to northern people. It has a discontinuous circumpolar distribution, with the northernmost areas of its range in the North Water between Canada and Greenland and at Svalbard, and the southernmost extent in the St. Lawrence River estuary, White Sea, Okhotsk Sea, Gulf of Alaska, and James Bay (Stewart and Stewart 1989). Beluga populations in the Arctic undertake annual migrations between summering and wintering areas, often crossing international boundaries. Belugas are conspicuous in some coastal areas, in river mouths and estuaries. Belugas probably mate in the early spring (Cosens et al 1993), so they may or may not be mating with the same animals that congregate in their summering areas

Methods

Results

Conclusion