Copulation attempts were observed at a colony of lesser kestrels, Falco izautnanni, in southern Spain in 1989 and 1990. Of 1397 observed copulation attempts, fr7% were extra-pair copulations. Ten of the 13 focal pairs showed a seasonally bimodal pattern of daily copulatory rates. On average, the peaks occurred 65 and 5 days before the laying of the first egg. The mean number of copulations per female per clutch was 3262. The three other pairs, formed by one yearling and an older individual, had a single maximum at an average of 15 days before laying. Frequent copulations in the lesser kestrel might have several functions: the early peak would be almost certainly outside the females’ fertile period and would be related to pair bonding and sexual stimulation of the pair members. The peak closer to egg layingeould be related to sperm competition since most extra-pair copulation attempts occurred close to the date of lay. Male lesser kestrels followed a mixed reproductive strategy, but the success of the extra-pair copulation attempts depended on the females (the larger sex) and their pairing status. Unpaired females tended to accept copulations with already paired males, whereas paired females rejected extra-pair copulations. Both sexes follow a strategy that tends to advance their respective laying dates and hence improve their breeding success.

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