Bioclimatic prediction of the potential distributions of some weed species prohibited entry to New Zealand

Abstract

The computer program BIOCLIM was used to estimate climatically suitable areas for three weeds which are prohibited entry to New Zealand. For Parthenium hysterophorus, nowhere in New Zealand was predicted to be suitable. Part of the Hawkes Bay Region was predicted to be marginally suitable for Solarium elaeagnifolium. By using the computer program CLIMEX, climates for locations in other countries where Parthenium and Solarium are weedy were examined. Comparisons revealed no close matches with New Zealand locations, suggesting that predictions made on the basis of Australian climatic data were reliable. Thus the need for prohibition is doubtful, especially for Parthenium. For Sorghum halepense, extensive areas on the North Island and parts of the northern and eastern coasts of the South Island could potentially be invaded. Such results support the quarantine status of Sorghum as well as the current eradication campaign targeting this species. It is concluded that BIOCLIM can be used to assist quarantine decision-making by identifying those plants which are not climatically pre-adapted to invade New Zealand. © 1991 Taylor & Francis Group, LLC.