Spatial Dispersion and Agonistic Contacts of Male Bush Crickets in the Biotope

Investigated the dispersion patterns of singing male bush crickets (Tettigonia cantans) and analyzed the behavioral patterns of established males elicited by the song of a conspecific. Results show that, apart from sites with sparse vegetation, stridulating males tend to show clumped distribution in areas with dense plant populations and that, within clumps, individuals are regularly spaced. Males seem to space themselves according to the song intensities they receive from each other. Between-close-neighbors rivalry behavior is expressed by males producing alternating songs, in an approach toward a constantly singing insect, or in an aggressive encounter. Of these 3 behavior patterns, aggressive encounters are most common in high-density populations. Rivalry does not influence the dispersion pattern of the males. A hypothesis is inferred from observations on female behavior: Rivalry itself constitutes an attractive stimulus for females. The problem still left for further research is if, and how, female bush crickets discriminate and choose their mate from a population of singing males.