Population ecology of the red wing grasshopper, Celes skalozubovi akitanus (Orthoptera, Acrididae) in Japan

Abstract

The red wing grasshopper, Celes skalozubovi akitanus has been declined rapidly in Japan, and only a few populations have been recorded. Information about ecological characteristics such as food plants, phenology and mating behavior are strictly limited, and population demographics of the grasshopper in its habitat is still unknown. Consequently, conservation actions for C. s. akitanus population are urgently needed in Japan. We studied the population structure and basic ecology of C. s. akitanus, to enable the conservation management of the grasshopper and its habitat. A field survey using the transect counts and mark release recapture method was conducted for two years (2016 and 2017). We revealed that C. s. akitanus in the study area fed on a variety of grassland plants but not on the dominant Miscanthus sinensis and Pteridium aquilinum. The recapture rate of C. s. akitanus is considerably high, about 68% or more, and the two isolated populations were found in the studied grassland. The estimated total population size is less than 120 to 140 individuals, indicating that the studied population is extremely small. Our results showed that this species has a strong sedentary behavior because most of the adults move less than 5 m in one season, and strongly prefer a bare ground within the grassland. The continuing implementation of annual prescribed burning and partial mowing in the habitat is important for the conservation of C. s. akitanus. In addition, creating continuity between two populations is effective for the survival of populations in this study area.