American Kestrel (Falco sparverius) Science Article 1
The American kestrel, Falco sparverius, has sex-related differences in habitat use during thenon-breeding season, with females occupying more open habitats than males. Two competinghypotheses have been proposed to explain this phenomenon: (1) males and females prefer differenthabitats, and (2) males and females prefer similar habitats, but larger females exclude smaller malesfrom preferred areas. This study experimentally investigated habitat selection in wintering kestrels bytemporarily removing kestrels from areas, and then observing the numbers and sex of the kestrels thatoccupied vacated areas. The home ranges of 20 birds (10 males and 10 females) were mapped and theiroccupants removed. Areas vacated in early winter (November 1994) were filled more quickly than thosevacated in late winter (February 1995).
DANIEL R. ARDIA and KEITH L. BILDSTEIN, Anim. Behav., 1997, 53, 1305-1311