Acoustic satellite behaviour in the Australian bushcricket Elephantodeta nobilis (Phaneropterinae, Tettigoniidae, Orthoptera)

Male and female Elephantodeta nobilis duet with the female responding to th e male's long and complex call. The duetting male's call consisted of four parts, described here as parts A, B, C and D. We found that the female repl ied 570 ms after the male's D pulse, which followed the extended part B and short click of part C. Noncalling males were attracted to the duet and oft en used satellite tactics by inserting a volley of clicks 200 ms before the alpha male's D pulse. Satellite males used part C of the alpha male song t o cue their own call and this inserted call induced females to reply earlie r compared with the alpha male call alone. Alpha males often extended their calls with additional D-type calls and so we examined the effectiveness of these calls as countermeasures to satellite,calling, There was no influenc e of this alpha strategy on the satellite's propensity to call although mor e calls from the alpha male did cause the female to reply more frequently. We also examined the effect of relative intensity of alpha and satellite ca lls on the female's reply. Reduced satellite intensity increased the varian ce in the timing of the female response. Finally, we tested the effectivene ss of the satellite's call on female phonotaxis within a two-speaker arena. Although females preferred the alpha male they were nevertheless attracted to the satellite calls regardless of the latter's relative intensity. We d iscuss the possible role of satellite calling as a novel conditional Strate gy. (C) 2000 The Association for thr Study of Animal Behaviour.