Paternity assurance in two species of colonially breedingfalcon: the kestrel Falco tinnunculus and the red-footedfalcon Falco vespertinus

Mate-guarding and frequent within-pair copulations are the two main paternityguards of male birds. Some species of birds of prey depend on large foraging areas due tothe availability and dispersion of their food, and males supply their females with food frommating until early chick rearing. Furthermore, birds of prey often must prevent their nestsfrom take-overs by nest-guarding. Therefore, males cannot prevent extra pair copulationsonly by mate-guarding. In this study we examine different parameters determining the twopaternity assurance tactics for a kestrel Falco tinnunculus colony, which are usually solitarybreeding and a similar sized colony of red-footed falcon Falco vespertinus, a colonial species.Kestrel pairs spent more time together near the nest than red-footed falcons and female redfootedfalcons were off the nest alone for longer time than female kestrels. Kestrels alsoshowed higher copulation frequency and duration than red-footed falcons.

Rottraut Ille et al., Etologia, 10:11-15 (2002)