HANEDA, Kenzo and Mitsuhiro KOIZUMI (Shinshu Univ. Nagano) Life history or the Black-Eared kite (Milus migrans lineatus) I. Breeding season Jap. J. Bcol. 15,199-215 (1965). This report deals with nest building, copulation, egg laving, incubation, hatching, chick raising, fledging, family stage, roost, share of male and female in breeding season, territory and productive relations of life in during the breeding season of the Black-eared Kite, based on the results of the outdoor observations for the purpose of studying the life history of the birds in the Zenkoji basin (altitude 350-360m) in the northern part of Nagano Prefecture from November 1962 to January 1965. The main part of the observations was done in the Koshoku district in the southern part of the basin, and most of the life history during the breeding season of the bird was described based upon the observation of one nest in 1964.