The ecological dynamics of pest-resource-people systems

Abstract

Pest problems involve people who value a resource affected by a pest that is managed by people, ideally the same as those who value the resource. Management that is not inclusive of pests, resources, people, and their interactions usually fails. Mammalian pests in New Zealand are of two sorts: those that are pests in their native land (usually r- strategists), and those that are not (usually K- strategists). The impact on New Zealand resources of r-strategists tends to be periodic and acute when their densities are high. Control works best against them when it is applied once densities become intolerable, or once such densities can be predicted. The impact of A'-strategists is more stable but is chronic. Control operations against them need to be sustained and regular to retain the stability of the pest-resource interaction, but to drive it in favour of the resource. The basic strategies to deal with the impact of pests are: those for which a one-off management action has a permanent benefit (e.g., eradication); those that require ongoing action to gain a permanent benefit (e.g., sustained control); and those for which no management action is possible or justified. Idealist and cynical approaches to pest policies are discussed and rejected in favour of a pragmatic policy. © 1993 The Royal Society of New Zealand.