Observations on stridulatorp, agonistic, and mating behaviour ofHemideina ricta(Stenopelmatidae: Orthoptera), the rare Banks Peninsula weta

Abstract

The stridulatory mechanism of Hemideina ricta, and its use during agonistic and mating behaviour, are described. The mechanism is of the femoral-abdominal type and it closely resembles that of H. maori. Broad-band non-resonant sound (3-5kHz peak) is produced as groups of approximately 5 syllables each, by males during (a) agonistic encounters and (b) mating rebuffs from females. The stridulation was also produced in agonistic and mating attempts with the sympatric weta H. fermorata. Conservation-oriented studies of H. ricta should establish whether gallery availability limits population expansion, whether male territorial and aggressive behaviour results in male exclusion from galleries, and to what extent wetas are at risk of predation as a result of occupying logs on the ground.