Effect of supplemental feeding on nesting success in the Lesser Kestrel (Falco naumanni)

The effect of food supplement to Lesser Kestrel (Falco naumanni) nests during the nestling period (from hatching to fledging) was studied in two nesting colonies in Israel - Alona and Jerusalem. Our hypotheses was that food supplement will have a greater effect on fledgling success in the food-limited, urban colony of Jerusalem, than in the rural colony of Alona. Indeed, food supplement had a significantly positive effect on breeding success in both colonies. However, and contrary to our prediction, the decrease in chick mortality between supplemented and control nests in Jersualem was actually smaller than in Alona. This implies either that additional factors, possibly urbanization associated, other than food limitation, might be responsible for the difference in nesting success of Lesser Kestrels between Alona and Jersualem, and/or that the amount of additional food provided to supplemented nests (three mice per chick per week), was not enough.