Do chewing cues from drywood termites mediate recruiting for wood colonization?

Abstract

Drywood termites, Cryptotermes brevis (Walker) (Isoptera: Kalotermitidae), are eusocial insects living and foraging in groups inside pieces of wood, in which they perform a suite of behavioral traits ranging from individual to coordinated group activities. Vibroacoustic cues play important roles in behavioral mediation during defense and foraging activities. However, termite societies also exhibit other relevant behaviors, including substrate selection for colony establishment, which has received little attention. Therefore, we tested the hypothesis that vibrational cues produced by termites inside pieces of drywood influence wood recruiting of conspecifics using dichotomous choice tests. In addition, we assessed whether the choice affects colony success (i.e., termite survival and wood consumption). Two behavioral activities were recognized among drywood termites colonizing wood galleries walking and chewing. However, only the chewing cues overcome background noise, allowing acoustic signal characterization and playback tests; thus, they were the focus of our study. Overall, drywood termite groups exhibit random choice among wood-testing unities, indicating that the chewing cues from the natural and/or playback signals are not used as a social trigger to mediate conspecific recruiting for wood preference and colonization. Nonetheless, the establishment of termite colonies in infested vs. non-infested wood pieces led to better termite performance in the former, exhibiting higher wood consumption and survival.