Seasonal Change in the Physiological Age Composition of Tabanus nipponicus (Diptera, Tabanidae)

In periodical collections of adult females by CO_2-baited traps, Tabanus nipponicus was the most abundant for three consecutive years, representing 78% of individuals collected among the thirteen collected species, and the adult activity extended over three months. The parous rate was 44% on the average and the rate of nectar ingestion was 64% in the studied population. The seasonal change of parous rate did not show the pattern typical of anautogenous species. It is likely that newly emerged females successively join the adult population throughout the entire season.