Coexistence of two related bush-cricket species (Orthoptera: Tettigonia caudata, T. viridissima) in an agricultural landscape

Competition is a basic type of interaction between species. Because complete competitors cannot exist in one habitat, closely related species must show at least slight differences in their biology or ecology. In the present study, we analyzed the habitat use of the two closely related bush-cricket species Tettigonia caudata and T. viridissima which often occur syntopically. The meso- and microhabitat use of males was compared in an agricultural landscape in NE Germany. Males of both species were found to use similar mesohabitats and to prefer dense and high vegetation. Microhabitats differed significantly in two aspects: Microhabitats of T. caudata had a higher proportion of herbs, while T. viridissima used higher song posts. These differences in microhabitats might explain the co-occurrence of the bush-crickets in open habitats. However, variation between the two species might also take place during other life-cycle stages such as during egg development.