Sex differences in the timing of spring migration of adult European Honey Buzzards Pernis apivorus in the Central Mediterranean

During spring migration, in several species of birds males tend to reach earlier than females the breeding grounds to occupy the best territories. Because of this competition, in some species males tend to migrate on shorter distances than females to cover shorter flyways in spring. A previous study made in the wintering grounds suggested that this could be the case of the European Honey Buzzard (Pernis apivorus), a migrant raptor breeding in Western Palearctic and wintering south of the Sahara desert. To verify if a differential timing of spring migration between sex classes occurs in this species, a 5-year study was carried out at the Strait of Messina, a bottleneck located along the Central Mediterranean flyway, between 8 April and 31 May 2019–2023. The results showed that, as predicted, the passage of adult males occurs a few days earlier. In particular the median dates of the passage occurred May 2nd and May 8th, for males and females respectively.