Fidelity to Breeding Area and Mate in Sparrowhawks Accipiter nisus

(1) On territories where occupants were identified in successive years, 57% of cocks and 50% of hens had changed between one year and the next. These figures gave mean periods of residence on territories of 1.4 and 1.5 years respectively, but occasional cocks stayed on the same territories for up to 5 years, and occasional hens for up to 6 (in a 10-year study). Turnover was more rapid on poor territories than on good ones. It was due partly to mortality and partly to movement. (2) Of birds identified in the next year, 77% of cocks and 67% of hens were on the same territory, and the rest were on a different territory. The median distance moved by cocks which changed territory was 0.8 km (maximum distance 19 km), and by hens 1.5 km (maximum distance 27 km). The minimum distance between nesting territories was 0.4 km.