Population genetic structure and the effect of founder events on the genetic variability of moose, Alces alces, in Canada

Moose, Alces alces, occur naturally throughout most of Canada but successfu l introductions of known numbers of animals have been made to the islands o f Newfoundland and Cape Breton. Five microsatellite loci were used to inves tigate the population genetic structure and any change in genetic variabili ty due to founder events of moose in Canada. Comparisons of allele frequenc ies for moose from 11 regions of the country suggested that there are at le ast seven genetically distinct populations (P < 0.05) in North America, nam ely Alberta, eastern Ontario, New Brunswick, Cape Breton, Labrador, western Newfoundland, and the Avalon Peninsula of Newfoundland. The average popula tion heterozygosity was approximately 33% (range from 22 to 41%). UPGMA ana lysis of Nei's genetic distances produced phenograms similar to what would be expected when geographical location and population history are considere d, The loss of heterozygosity due to a single founder event (n = 3; two int roductions and a natural colonization) ranged from 14 to 30%, and the cumul ative loss of heterozygosity due to two successive founder events (an intro duction followed by a natural colonization) was 46%. In these examples loss of genetic variability has not been associated with any known phenotypic d eviances, suggesting that populations may be established from a small numbe r of founders. However, the viability of these founded populations over evo lutionary timescales cannot be determined and is highly dependent upon chan ce.