Parasitism rate of Plebejus argyrognomon (Lepidoptera: Lycaenidae) under different levels of mowing management

Plebejus argyrognomon is an endangered grassland butterfly species in Japan. In this study we focused on the parasitism rate of tachinid flies under different mowing management to obtain knowledge of this possible top‐down effect that has been largely ignored. We established three mowing treatments differing in the intensity of mowing, as represented by vegetation height. The results showed that the parasitism rate of P. argyrognomon increased with vegetation height; the parasitism rate in blocks subjected to the highest mowing intensity was 8%, whereas in blocks subjected to the lowest mowing intensity, the rate was 42%. We suggest that clarifying interspecific interactions is important for understanding how habitat management affects grassland‐inhabiting butterflies in general. In this study, we focused on the parasitism rate of tachinid flies under different mowing management. We established three mowing treatments differing in the intensity of mowing, as represented by vegetation height, and found that the parasitism rate of P. argyrognomon increased with vegetation height, in areas subjected to lower mowing intensity.