Identification of suitable habitats is an important first step toward conserving grassland bird populations. Here, I investigated habitat preferences of five grassland bird species, including two endangered species, in a breeding season at Hotokenuma wetland in northeastern Japan. The five species were the Japanese marsh warbler Locustella pryeri, Oriental Reed Warbler Acrocephalus orientalis, Black-browed Reed Warbler A. bistrigiceps, Reed Bunting Emberiza schoeniclus and Japanese Reed Bunting E. yessoensis. The results showed that the Japanese Marsh Warbler, Reed Bunting and Japanese Reed Bunting preferred similar habitat: the height of the reed Phragmites australis is low and the height and density of monocotyledons or dicotyledons is high. The black-browed Reed Warbler used various habitats in the study area relatively equally, whereas the Oriental Reed Warbler preferred habitat with tall reedbeds and a high density of monocotyledons. To conserve these species, various type of grassland habitat should be preserved.
