Pinyon engraver beetle acoustics: Stridulation apparatus, sound production and behavioral response to vibroacoustic treatments in logs

Abstract

Bark beetles are among the most influential biotic agents in conifer forests, and forest management often focuses on bark beetle chemical communication for tree protection. Although acoustic communication occurs in many bark beetle species, we have yet to utilize acoustic communication for bark beetle control. Here, we describe the stridulatory organs and ‘stress’ chirps of the pinyon engraver, Ips confusus, a significant pest and mortality agent of pinyon pine in western North America. Only females possessed stridulatory organs and their stress chirps varied significantly in duration, pulses per chirp, and dominant frequency. We tested an array of acoustic-vibrational treatments into logs but were unable to disrupt male entry into logs or alter female–male interactions, female tunneling, and female oviposition. We found acoustic–vibrational treatments had little effect on I. confusus behavior and suggest further studies if acoustic methods are to be utilized for bark beetle control.