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Providing evidence to improve practice

Individual study: Effectiveness of a long-term, volunteer-based nest box programme for American kestrels Falco sparverius in Berks, Lehigh and Schuylkill counties, Pennsylvania, USA

Published source details

Katzner T., Robertson S., Robertson R., Klucsarits J., McCarty K. & Bildstein K.L. (2005) Results from a long-term nest-box program for American kestrels: implications for improved population monitoring and conservation. Journal of Field Ornithology, 76, 217-226


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Provide artificial nesting sites for falcons Bird Conservation

A replicated study in a 1500 km2 area of mixed deciduous forests in Pennsylvania, USA (Katzner et al. 2005), found that American kestrels Falco sparverius used an average of 86 nest boxes each year between 1993 and 2002 (32% of the approximately 270 boxes in the area). Pairs laid an average of 4.6 eggs/clutch and fledged 2.7 nestlings/box (171 boxes monitored). First breeding attempts were successful 69% of the time. These productivity levels are similar to those recorded elsewhere. Boxes were 26 × 24 × 33 cm, with a 7.6 cm diameter entrance hole. They were erected 3–6 m off the ground (usually on trees or utility poles, but sometimes on sheds and barns).