BAITING STUDIES AND CONSIDERATIONS WITH COPTOTERMES-FORMOSANUS (ISOPTERA, RHINOTERMITIDAE) IN HAWAII

This paper summarizes preliminary results of three field studies of th e efficacy of a prototype commercial baiting system using the chitin i nhibitor hexaflumuron against the Formosan subterranean termite, Copto termes formosanus Shiraki (Isoptera: Rhinotermitidae). Using mark-rele ase-recapture methods, termite foraging populations at these three sit es were estimated at 0.33 million, 0.94 million, and 5.35 million. Fol lowing application of hexaflumuron baits, no termite activity has been detected at these locations for 24, 10, and 20 months, respectively. At these sites, the amount of bait consumed had a logarithmic relation ship to the size of the estimated populations, although in each case t here was a great deal of variation among the individual population est imates used to calculate the weighted-mean population estimate. We arg ue that monitoring of termite activity at unbaited foraging sites is e ssential in order to document bait efficacy without the confounding fa ctors of bait deterrence and/or localized termite mortality at the sit e of bait application. We conclude that suppression or removal of the termite population to a level where termite activity can no longer be detected in unbaited monitoring stations, in the structure to be prote cted, or elsewhere in the immediate vicinity of the structure is the o nly practical goal of bait applications.