Pheromone-Food-Bait Trap and Acoustic Surveys of Rhynchophorus ferrugineus (Coleoptera: Curculionidae) in Curacao1

ABSTRACT Pheromone-food-bait trap and acoustic surveys were conducted in Curacao to monitor a recently discovered invasion of Rhynchophorus ferrugineus L. (RPW). This pest of economic importance in regions of Asia, the Middle East, and the Mediterranean was not observed in the Americas until 2009. Due to its economic and environmental damage, there is an urgent need to manage or eradicate RPW in Curacao to reduce its impact on the island as well as avoid the possibility of transference to surrounding regions. Studies were conducted to explore methods available for monitoring adults with traps and acoustically assessing larval infestations in trees in the warm, dry but humid Curacao environment - considering also some special challenges of urban conditions, such as increased traffic noise or unwanted human curiosity that could negatively affect monitoring success. Bucket traps baited with 4-methyl-5-nonanol/4-methyl-5-nonanone pheromone lure, ethyl acetate and a molasses - ethylene glycol mixture captured RPW adults at consistent rates for ca. 7/d, but the rates of capture were reduced for the 9th to 14th d of a two-week sampling period. The weevils were observed to escape rapidly from dry traps but not from liquid-containing traps. A portable, user-friendly acoustic sensor system enabled identification of larvae in individual infested trees through the use of signal processing analyses that screened out bird and wind noise. This information gained about liquid baits and acoustic differences between background noise and RPW-produced sounds can assist future efforts to monitor, control, or eradicate RPW in Curacao as well as other urban landscapes.