Predicting the seasonal phenology of fall webworm (<i>Hyphantria cunea</i>) in New Zealand

Abstract

A cohortbased model for the seasonal phenology of the blackheaded strain of the fall webworm Hyphantria cunea (Lepidoptera Arctiidae) was constructed from published development rates for each life stage Model predictions were successfully verified against field observations from Japan China Italy Serbia and the USA The model was then used to predict phenology in New Zealand and the potential for establishment near major ports Populations are predicted to be bivoltine in the north and univoltine in central areas but are unlikely to form selfsustaining populations south of Timaru Fall webworm demonstrated the ability to adapt to specific local conditions after its invasion of Japan so the risk may be greater than these results suggest Successful validation of the model means that it could be used to inform surveillance and control operations targeting fall webworm outbreaks overseas and potential invasions into new ranges such as New Zealand