The Periodic Invasions of Goshawks

Differential Timing of Autumn Migration between Sex and Age Groups in Raptors at Falsterbo, Sweden

“…In all three species juveniles have been shown to winter farther south than adults (Schelde 1960, Haukioja and Haukioja 1970, Mueller et al 1977, Kjell6n 1990. In all three species juveniles have been shown to winter farther south than adults (Schelde 1960, Haukioja and Haukioja 1970, Mueller et al 1977, Kjell6n 1990.…”

“…The Social Dominance Hypothesis (Gauthreaux 1978, Mueller et al 1977, Newton 1979 proposes that differences in seasonal timing of migration and winter distribution of partial migrants are related to social status. Less experienced birds (juveniles) and the smaller sex (in raptors normally males) are supposed to migrate further from the breeding grounds and on an earlier autumn migration schedule than adults and females respectively.…”

Territoriality and Habitat Use of Common Buzzards (Buteo buteo) During Late Autumn in Northern Germany

“…This, moreover, is predicted for partial migrants by the social-dominance hypothesis (Cox 1968, Mueller et al 1977, Gauthreaux 1978, 1982.…”

Movements of the Goshawk in Estonia: an analysis of ring recoveries

“…However, the pattern differs between regions. In North America, most adult birds stay in territories while others migrate south and periodic or aperiodic invasions have been recorded (Mueller et al 1977, Squires & Kennedy 2006. The migration of adult birds has also been noted in Asia (Kudo 2008).…”

“…Additionally, dispersal, a movement between natal and breeding areas, or between subsequent breeding sites, can shape the spatio-temporal pattern of animal populations (Greenwood & Harvey 1982, Paradis et al 1998. Each species has its characteristic movement pattern, but there is also intraspecific variation, which may depend, for example, on the age and sex of individuals (Mueller et al 1977, Clarke et al 1997. Birds are well suited to migration and dispersal studies as their movements can often be observed visually and they can be marked using various techniques (Kumari 1975, Nichols et al 2004, Varland et al 2007.…”