A Bioeconomic Model of Little Fire Ant Wasmannia auropunctata in Hawaii

Reports were scanned in black and white at a resolution of 600 dots per inch and were converted to text using Adobe Paper Capture Plug-in.Wasmannia auropunctata, known as the Little Fire Ant (LFA), was first detected on the island of Hawai‘i (the Big Island) in 1999. It was most probably introduced through imports of contaminated potted plants from mainland USA. We estimate that LFA has now spread to over 4,000 locations on the Big Island and under current management efforts will spread rapidly inundating the Big Island in 15-20 years. Increased efforts in prevention, detections, and mitigation treatments will suppress existing infestations, reduce rate of spread and decrease long term management costs, damages, and human stings. Benefits from increased management are estimated to be $5 billion savings including$540 million in reduced damages and 2.1 billion fewer sting incidents over 35 years.This research was supported in part by the Tropical and Subtropical Agriculture Research (TSTAR) Program (Award Number 2010-34135-21228), The National institute of Food and Agriculture (NIFA), US Department of Agriculture (USDA

Eradicating Wasmannia auropunctata (Hymenoptera: Formicidae) from Maui, Hawaii: The Use of Combination Treatments to Control an Arboreal Invasive Ant

A small infestation of Wasmannia auropunctata (little fire ant) was discov- ered on the island of Maui, Hawaii in September 2009. After delimiting the infestation, we treated it on twelve occasions over the course of a year using two types of granular baits for the ground layer and a paste bait containing indoxacarb (0.18% a.i.) on the vegetation. These treatments rapidly reduced the W. auropunctata population with only a single ant recorded after five months treatment and none thereafter. To date, one year after initiation of treatments, no further positive detections have been observed and we tentatively report the eradication of this species from Maui. The key components of the treatment program contributing to its success to date have been the baiting of arboreal nests with a formulation designed for use on vegetation and the strategy of baiting repeatedly even after no ants could be detected with conventional survey methods. The response to the detection of this invasive species on Maui is a successful example of multi-agency collaboration and cooperation necessary for invasive species management. We recommend that future eradication and control attempts for this species include treatment of the arboreal components of infested habitats

Long-term ant community responses to selective harvesting of timber from Spotted Gum ('Corymbia variegata')-dominated forests in south-east Queensland

The conservation of biological diversity is a fundamental consideration in the management of production forests in eastern Australia. Invertebrate communities make up the bulk of diversity in these forests, yet few studies have been conducted to determine what impact, if any, timber harvesting may have on their structure, dynamics or diversity. We report here on a space-for-time study conducted in an open eucalypt production forest in south-east Queensland that investigated the long-term effects of selective timber harvesting on the ground-active ant community. Over a notional 30-40 year logging cycle, there were significant changes in the composition of ant functional groups, no significant changes to ant abundance and a weak trend to reduced ant species richness as time since harvesting increased. However, when ant community composition was compared with logging history and other environmental variables using a range of statistical tests, only small changes in ant community composition were attributable to timber harvesting. This suggested that the ant community was at least partially controlled by factors other than management history or the environmental variables measured in this study. The diversity, abundance and organization of ant communities is therefore unlikely to be detrimentally affected by selective harvesting of timber, as currently practiced in state-owned forests in south-east Queensland