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FUCHS P & J VAN DE LAAR (2008) Dispersal and settlement of young Little Owls Athene noctua. LIMOSA 81 (4): 129-138.

During 1972-1989 a population of Little Owls was studied in the Central Betuwe, an area between the Lower Rhine and Waal rivers in the province of Gelderland measuring 100 km2 (Fig. 1). The study was initiated to estimate the impact of changes in landscape (disappearance of tree orchards) and agricultural practice on density and reproduction of the species. This article focuses on the dispersal and the chances of settlement of young Little Owls in their natal area.
      After three years of ringing nestlings and adults, 56-79% of the trapped adultswas found to have been ringed earlier (Tab. 1). Breeding adults mostly stayed in the same breeding territory: only 6% of 352 retrapped birds moved to a different territory in the course of the study. The largest distance was covered by a female resettling 1600 m from her previous breeding site. Of the ringed nestlings only 8% was recovered breeding within the study area, most of them (65%) in their first year (Tab. 2). Nestlings found breeding within the study area settled on average at 2689 m from their place of birth; this must be regarded as aminimumsince birdsmoving out of the study area were less likely to be detected. Altogether the results point out that young Little Owls are highly resident and adults show high territory fidelity. Males tended to stay closer to their natal nest (Fig. 2), and were more often found breeding within the study area than females (35% vs. 15%). Young born in the more strongly degraded landscape of the western part of the study area dispersed further than young from the more intact eastern part, probably reflecting that birds in the western part have to cover a larger distance tomeet suitable breeding habitat. Recruitment rate of nestlings (as breeding adult) fluctuated with winter severity. Of young hatched in 1978 (followed by a severe winter with 36 days of snow cover), only 4% were found breeding in later years, contrasting with 12-14% found in earlier and slightly less than 10% in later years (Tab. 2). Young that were born early in the season more often settled within the study area (11%) than young born late (8%; Tab. 3).

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limosa 81.4 2008
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