冬季におけるカワガラスCinclus pallasiiの分散様式となわばり的行動 DISPERSION PATTERN AND TERRITORIAL BEHAVIOR OF THE WINTERING BROWN DIPPER, CINCLUS PALLASII
In winter, brown dippers are mainly solitary and exclusive in relationship with adjacent conspecific individuals. They drive other individuals out of their surrounding spaces along stream by threat (warning call, confronting) or aggressive behavior (chasing flight). The area along the stream, where a dipper can find others approaching is limited, and this area is defended as a territory. Some individuals are observed within narrow ranges (Sedentary type), and they held stable territorial ranges. On the other hand, others (Nomadic type) live within more extensive ranges, and change their territorial ranges day by day. Roosting individuals in upstream areas must be nomadic ones and they come downstream for feeding during the daytime.
日本生態学会誌 31(2), 161-170, 1981