Mole Cricket Phonotaxis: Effects of Intensity of Synthetic Calling Song (Orthoptera: Gryllotalpidae: Scapteriscus Acletus)

Abstract

The sound pressure level of the natural call of S. acletus is 70 to 90 dB (measured at 15 cm). Within this range louder males attract many more conspecifics than do quieter males. Because traps that broadcast simulated calling songs at >90 dB catch enormous numbers of mole crickets, the upper limit of greater phonotaxis to higher sound levels is important to sound trap design. In three series of tests of traps broadcasting synthetic calling songs differing by 12 dB, the louder trap captured 3 to 9 times as many mole crickets as the quieter one. The effect was significantly greater in trials of 94 vs 106 dB and of 106 vs 118 dB than in trials of 116 vs 128 dB, but we failed to find the upper limit we were seeking. At all intensities a greater proportion of females than males landed within 0.76 m of the speaker.