Status of Three Pestiferous Fruit Fly (Diptera: Tephritidae) Populations on Kauai Following Hurricane Iwa

Abstract

The eye of Hurricane Iwa surrounded by cyclonic winds of 144 km/h and gusts up to 176 km/h passed within 32 km of Niihau and Kauai on Nov. 23, 1982. Upper story vegetation was heavily damaged over large portions of Kauai with pronounced impact on some fauna. Fruit fly surveys had been conducted over a period of nearly 5 years prior to the hurricane to establish distribution and seasonality of the oriental fruit fly, Dacus donate Hendel, the melon fly, D. cucurbitae Coquillett, and the Mediterranean fruit fly, Ceratitis capitata (Wiedemann). This baseline information provided the impetus for assessing the ecological implications the hurricane may have had on numbers of adults present up to the fifth week following the hurricane. Both the oriental fruit fly and melon fly occupied dense vegetation sites that provided protection to habitat and host plants. Also, populations were sufficiently distributed and abundant to sustain the highest percentage reduction in numbers. Medfly, in contrast, was not captured in the island peripheral habitats and storm damage appeared to have impacted most on this species. While oriental fruit fly was trapped at the rate of hundreds/trap/day and melon fly in tens, no medflies were captured using both Jackson and McPhail traps in a concerted effort. Medfly likely was reduced to a low remnant population in isolated pockets of inland host material such as feral coffee and guava that were protected from strongest winds.