The breeding biology of the White-spectacled Bulbul, Pycnonotus xanthopygos, at the northwestern edge of its distribution range

Abstract

The White-spectacled Bulbul, Pycnonotus xanthopygos, is an abundant and possibly invasive species in Turkey, where it has gradually expanded its distribution and breeding range in both western and southeastern directions. This study focused on its breeding biology, which is still poorly known. The breeding activity extends from February until September. The preferred nesting areas are mainly gardens and maquis groves, where 24 different nesting tree species have been identified. The clutch size is 3.3 ± 0.8 eggs per pair, nesting success 68%, hatching success 94%, fledgling success 95%, and overall breeding success 89%. While nesting success differs significantly between the years, we found no significant differences in hatching, fledging, and overall breeding success between the years studied. Despite favourable climatic conditions in the Mediterranean region, the species makes only one brood per year in a relatively extended breeding season extending over seven months, and has a relatively a high reproduction rate per nest.