Pheromones for pest management and eradication of invasive species.
Surveillance is a key component to pest management and biosecurity and the availability of attractants for certain insects has revolutionised our ability to intervene against them. In fact, the improvement in success of eradication when attractants are available is more than 20-fold, according to a recent global study. Populations of such invasive species with urticating hairs and a wide host range as tussock moths or processionary moths can be controlled or eradicated when these tools are available for delimitation and suppression, and in New Zealand several eradication programs have been operated successfully. Examples are white-spotted tussock moth (Lymantriidae), painted apple moth (Lymantriidae), fall webworm (Arctiidae), Hokkaido gypsy moth (Lymantriidae). In other cases, it has not been possible to eradicate the organism, such as the defoliating gum leaf skeletoniser (Nolidae), an outbreak species in Australia and now widely dispersed in New Zealand. The identification and deployment of this insect illustrates the surveillance paradigm well. Beyond applications in surveillance, it is also possible to consider aerial application of mating disruption with various formulations, such as those recently compared in a New Zealand study on a tortricid (microencapsulations, SPLAT and a bioflake) with the ground application of a polyethylene tubing dispesnser. Pheromones can also be envisaged to be developed in other new ways, from mobile mating disruption to ant trail pheromone disruption. New trapping and surveillance tools and new concepts for biosecurity from can widen the tool kit we need to combat invasive species. A deep knowledge of chemical ecology is needed to face this challenge.