(1) The territoriality, pair duration, and feeding habits of two species of wagtails, Motacilla gandis and M. alba, were studied in winter along a river in Utsunomiya, central Honshu.
(2) Territories of the two species overlapped each other to a great extent. In some cases the territorial boundaries of the two species nearly coincided with each other, but their activity centers tended to be located in different parts of the shared territory.
(3) M. grandis lived mostly in pairs, whereas many individuals of M. alba lined singly. The boundaries of territories were distinct in M. grandis but often vague in M. alba.
(4) M, grandis spent much more time on the river; M. alba sometimes went far away from the river. The greater dependence of M. grandis on the river was considered to be linked with the sharp defence of territory and stable pair duration.
(5) The difference in feeding technique between the two species was small. However, there was a significant difference in the places preferred for ground feeding, the technique most often used by both species.