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Résumé :
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Ring recoveries were used to explore the effect of early experience on the subsequent survival and dispersal of young Sparrowhawks in two areas in south Scotland. Young raised on high grade territories were recovered in greater proportion than young on low grade territories, implying that they had survived better after leaving the nest. Recovery rate tended to decline with increasing elevation of the nesting territory, implying that young from the high-ground territories survived less well than those from low-ground territories. Recovery rate showed no relationship with brood-size or sex composition, or with maternal age (yearling or older). After the post-fledging period, dispersal distances were greater in females than in males and showed significant increases with increasing elevation of nesting territory tone area only) and with lateness of laying (or fledging) date. Regardless of laying date, young males from yearling mothers also dispersed further than young from older mothers, and young males from high elevation territories further than those from lower territories. No significant relationships emerged between dispersal distances and grade of natal territory, brood size or sex composition.
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