Low levels of extrapair paternity in the long-lived colonial Alpine swift (Tachymarptis melba)

It has been suggested that a high aerial lifestyle makes it difficult for males to limit mating opportunities for their partners. This would explain the particularly high levels of extra-pair paternity (EPP) observed in swallows and swifts (Hirundinidae, Passeriformes). Here, we investigated EPP in the Alpine swift (Tachymarptis melba), whose aerial lifestyle is similar to that of the Hirundinidae, but which is a phylogenetically distinct taxon (Apodiformes). Here, we investigated EPP in the Alpine swift (Tachymarptis melba), which is a phylogenetically distinct taxon (Apodiformes), but whose aerial lifestyle is similar to that of the Hirundinidae. We found 9 cases of EEP in 9 broods out of 216 (4.2%) nestlings and 87 (10.3%) broods analysed. This low incidence of extra-pair paternities is similar to the only estimate reported so far in Apodiformes (i.e. 4.5% of nestlings in the common swift; Apus apus). We discuss the fact that the ecology (incubation of the clutch by both sexes in swifts versus female-only in swallows and martins) and life history (swifts are long-lived and can switch mate from one year to another), rather than aerial lifestyle, may explain the differences in EPP between swifts and swallows or martins.