Micro-encapsulated zinc phosphide for the control of brushtail possum (Trichosurus vulpecula) in New Zealand: an old poison finding new favour

Abstract

The brushtail possum is a signifcant epidemiological and environmental pest in New Zealand with US$30 million spent on possum control activities in 2002. The bulk of the control effort is reliant on the widespread, aerial delivery of bait containing sodium monofluoroacetate (1080). Over the past 10 years, the continued use of 1080 has come under rigorous public and scientific scrutiny. In response to these concerns, there has been an extensive search for cost-effective and 'environmentally- safe' alternatives. Two promising alternatives have been cholecalciferol and brodifacoum although both have issues concerning risk to non-target avian and mammalian species.