Sjöberg, G. 1996: Genetic characteristics of introduced birds and mammals. - Wildl. Biol. 2: 159-164.
Introduced populations of birds and mammals may have genetic characteristics differing from those of naturally occurring populations. Such populations are often created by translocation of small numbers of individuals. This leads to founder effects and subsequent genetic drift, often resulting in larger differences in allozyme patterns between introduced populations than between naturally established populations. In many cases, a large proportion of alleles have been lost a few generations after the introduction. Under certain conditions, the mean level of heterozygosity is also severely reduced. Theoretically, a reduction in the number of alleles in a population will result in a lowered potential to track environmental changes, but there is scant evidence for this in introduced wildlife. Likewise, evidence is lacking for inbreeding depression occurring in introduced populations of birds and mammals in the wild. Finally, some conclusions are drawn concerning management strategies for wildlife introductions with respect to genetic considerations.
Key words: wildlife, species introductions, genetic variability, number of alleles, heterozygosity, founder effects, inbreeding
Göran Sjöberg, Department of Animal Ecology, Swedish University of Agricultural Sciences, S-90183 Umeå, Sweden