CALLING BEHAVIOR IN BUSH-CRICKETS OF THE GENUS POECILIMON WITH DIFFERING COMMUNICATION-SYSTEMS (ORTHOPTERA, TETTIGONIOIDEA, PHANEROPTERIDAE)

In bushcricket communication systems males have to signal acoustically to attract females. The calling activity, however, not only may incre ase mating success, but also may result in costs in terms of energy an d predation risks. In this study the calling activity of males and its timing during the day were analyzed for several species of the genus Poecilimon, representing two different communication systems. In speci es with mute females that approach the males phonotactically, calling was restricted to darkness and syllable rates were high. In species wh ere females respond acoustically to male song and thus can induce the male to approach them phonotactically, males called during both day an d night or during the day only, and syllable rates were low. After mat ing, male acoustic activity dropped to a very low level but was restor ed during the following 2 to 3 days, a time period longer than the min imal male mating interval. The results are discussed with regard to po ssible energetic limitations, the risk of attracting predators and par asitoids, and the spermatophore production of males.