Population genetics and conservation in New Zealand: A hierarchical synthesis and recommendations for the 1990s

The importance of understanding population genetics in planning effective management of small populations has been repeatedly emphasized. Inbreeding, loss of variation through drift, genetic differentiation among populations and identification of taxa have received particular attention. In this paper, I discuss the relative importance of these issues in a hierarchical framework, and suggest some means of resolving the debate surrounding them.

Small island populations of plants and animals around New Zealand present special opportunities for examining the bottleneck effects of both recent and prolonged inbreeding. In addition to island distributions, the age and isolation of New Zealand and its associated fauna and flora have permitted an impressive radiation in some groups. Perpetual representation of this phylogenetic biodiversity is clearly an important goal of conservation, but the systematics of many groups is poorly known. Comparative molecular methods now allow us to quantify this diversity from the level of the individual, through population and species, to the highest taxonomic divisions. The evaluation of this historical differentiation is important not only for decisions relating to breeding programs (i.e. maximising fitness of offspring by avoiding mating of closely related animals and those from different geographic subspecies): the objective recognition of biodiversity at the genetical level is also significant to our understanding of phylogenetic priority, and provides a common yardstick for various national conservation strategies.

Keywords:

• biodiversity
• conservation
• genetic differentiation
• inbreeding
• phylogeny
• population genetics

Notes

Department of Zoology and Centre for Gene Research, University of Otago, PO Box 56, Dunedin, New Zealand