Male responses to conspecific and heterospecific songs in two field cricket species

Many animals produce acoustic signals for displaying their territoriality to other males and attracting mating partners. However, the acoustic signals are often eavesdropped on by other species. If a species with higher competitive ability eavesdrops on the acoustic signals of a species with lower competitive ability, the former can deprive the latter of their suitable calling sites. Therefore, the species with higher competitive ability exhibits a positive response to the acoustic signals of those with lower competitive abilities, whereas the species with lower competitive ability exhibits a negative response to the calling songs of those with higher competitive abilities. In the present study, male responses to conspecific and heterospecific song in two field cricket species Teleogryllus occipitalis (Audinet-Serville 1839) (Gryllidae) and Loxoblemmus equestris Saussure 1877 (Gryllidae) were investigated by playback experiments. T. occipitalis has larger body size than L. equestris. Both species did not exhibit precise negative or positive responses to conspecific and heterospecific songs. The results suggest that the cricket species do not utilize heterospecific song to acquire their calling sites.