Biodiversity management: Lake Rotoiti choice modelling study

Abstract

Invasive species are non-indigenous species that adversely affect the habitat they invade. The adverse impact can be ecological (e.g. extinction of indigenous species), environmental (e.g. altering ecosystem function) and/or economic (e.g. reducing tourism). Introduced Vespula wasps have successfully invaded beech forests in New Zealand. They are now found throughout New Zealand up to altitudes of 1,600 metres. Honeydew, produced by an endemic scale insect which inhabits about 1 million hectares of beech forest land, is a key source of carbohydrate. Wasps also need protein which is sourced from insects and birds in the forest. These abundant invaders compete for food directly with indigenous species. They are also known to kill insects, pollinators, and young birds. Social wasps also impact business and reduce the quality of outdoor recreational activity. Values changed by wasps can be broadly described as use values and existence values. Examples of use value include recreation and viticulture. Existence values may arise from knowing that the habitat for endangered indigenous species is being preserved. Estimates of these values provide information to decision makers charged with allocating scarce funds for biodiversity conservation. This paper reports on the application of a choice experiment to estimate community preferences and values associated with the impact of wasps on indigenous species in the South Island. Economic valuation focuses on changes in utility associated with changes in the flow of services from the natural environment. In the case of wasps the aim is to measure the change in utility that attaches to changes in indigenous biodiversity.