Amplified fragment length polymorphism (AFLP) markers reveal extra-pair parentage in a bird species: the bluethroat (Luscinia svecica)

We tested the use of amplified fragment length polymorphism (AFLP) to asses s the frequency of extra-pair parentage in a bluethroat (Luscinia svecica n amnetum) population. Thirty-six families totalling 162 nestlings were analy sed. Using a combination of three primer pairs, we reached an exclusion pro bability of 93% for the population. This probability can reach 99% consider ing families independently. We revealed that extra-pair fertilizations are very common: 63.8% of all broods contain at least one extra-pair young, tot alling 41.9% of all young analysed. However, with the technique and the thr ee primer pairs used it was not possible to attribute the parentage exclusi ons to extra-pair paternity, maternity or both. As brood parasitism has nev er been reported in this species, it seems likely that the exclusions are d ue to extra-pair males. This study shows that dominant AFLP markers can be useful for studying the mating system of taxa for which no microsatellite p rimers are available. This technique allows the approximate estimation of p arentage exclusions despite the fact that it is not possible to know which parent has to be excluded.