female arriving from the nest site (left) finds the best food patches on the
occupied by earlier females which defend their territories vigorously (right).
The best feeding is at the very outlet where there is a high density of big blackfly larvae.
the arriving female tries to squeeze through the territory to get to unoccupied
(inferior) feeding sites further downstream, a series of interactions may
occur, which often lead to exchange of young and their amalgamation
into large groups. Each group is attended by one female only.
See what happens.
Close-up of a young
Árni Einarsson 1985. Use of space in relation to food in Icelandic Barrow's goldeneye (Bucephala islandica). Ph.D. thesis, University of Aberdeen, Scotland.
Árni Einarsson 1985. Dreifing húsanda með tilliti til fæðu. Bliki 4: 67-69.
Árni Einarsson 1988. Distribution and movements of Barrow's goldeneye Bucephala islandica young in relation to food. Ibis 130: 153-163.