Breeding rates of Eurasian Kestrels (Falco Tinnunculus) in relation to surrounding habitat in southwest Spain

We studied bleeding success of Eurasian Kestrels (Falco tinnunculus) in nes t boxes in seven different habitat types in the southwest of Spain. A total of 567 nest boxes was installed on power pylons in fallow fields, cereal c ropland, helm oak land, olive orchards, pastureland, irrigated cropland, an d shrubland. Occupation of bares did not vary among the habitats and there were no significant differences among the seven habitat types in laying dat e, clutch size, or breeding success. When habitats with low numbers of bree ding pairs were removed from analyses, we were able to detect significant d ifferences in mean laying dates, clutch sizes, and breeding success rates a mong the three habitat types with the highest sample sizes. Kestrels nestin g in pastureland showed higher clutch sizes and higher breeding success tha t those nesting in the cerealland. A seasonal decline in clutch size was fo und in all three habitat types with the highest sample sizes. Our results s uggested that habitat features influence che breeding biology of Eurasian K estrels.