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Timing, age classes and water-crossing behaviour of Black Kites (Milvus migrans) during spring migration across the Central Mediterranean The main migratory passage of Black Kites across the Mediterranean Sea occurs at the Strait of Gibraltar, where the migration peak is observed in early March. Conversely, in the Central Mediterranean the migration of this species is scarce during the supposed peak period, while hundreds of individuals are observed migrating later in the season, mostly in April and May. In the present study we investigate the spring migration of Black Kites at two sites of the Central Mediterranean, the island of Ustica and the Strait of Messina. Timing, age classes and water-crossing behaviour of this species suggest that large numbers of non-breeders use this route during spring. However, a peculiar migration timing of breeding pairs belonging to the Italian population cannot be excluded.

Analysis of the Spatial Migration Patterns of Adult Honey Buzzards (Pernis apivorus) During Spring and Autumn in the Central Mediterranean In this paper we analyse the spatial migration patterns and the water crossing tendency of adult Honey Buzzards during spring and autumn migration in the Central Mediterranean region. In this area, during spring, these long-distance migrants wintering in western-central Equatorial Africa, concentrate crossing the sea between Africa and Europe through the Channel of Sicily, about 150 km wide, at least part of them via the islands of Pantelleria and Marettimo. When they reach western Sicily most of them fly east, along the mountain chain of northern Sicily, towards the Strait of Messina. Nevertheless, thousands of birds use a more direct route to reach the continental mainland undertaking the crossing of the Tyrrhenian Sea via Ustica and the Lipari Islands. During autumn the migration of adult Honey Buzzards is less consistent. They tend to follow the Italian Peninsula and northern Sicily reaching Africa through the Channel of Sicily while very few cross the Tyrrhenian Sea. On the contrary, during their first migration, large numbers of juveniles, moving about two weeks later than adults, cross the Central Mediterranean region on a broader front presumably along NE-SW innate axis. It is supposed that larger numbers of adult Honey Buzzards choose the central Mediterranean route during spring migration to reach earlier their breeding areas in eastcentral Europe. During post-reproductive movements most of them would circumfly the Mediterranean Sea crossing at the Strait of Gibraltar and at the Bosporus. In this picture the discovery of more direct routes between breeding and wintering areas made by juvenile birds during their first migration may have the adaptive value.

Crossing the sea en route to Africa: autumn migration of some Accipitriformes over two Central Mediterranean islands Observations were made on the autumn migration of Accipitriformes over the islands of Marettimo and Pantelleria, located between western Sicily and Tunisia (Central Mediterranean). A total of 7451 raptors was counted between 24 August and 12 September 2003, mostly adult Honey Buzzards Pernis apivorus - 4045, and Black Kites Milvus migrans - 2489. Mixed-age flocks were regularly reported for the Black Kite (1956 adults and 533 juveniles estimated) confirming information transmission concerning orientation behaviour in this species. Although in the Honey Buzzard juveniles tend to migrate later than adults, crossing the Mediterranean on a broad front mostly after mid-September, we observed some mixed-age flocks, estimating the passage of 3830 adults and 215 juveniles. In particular, over Pantelleria we recorded in seven cases juveniles in flocks of adults heading towards WNW, presumably learning (similarly to juvenile Black Kites) the shortest route over water to reach Africa from this site. A total of 72 Egyptian Vultures Neophron percnopterus - 62 adults, 6 juveniles and 4 sub-adults - was counted over Marettimo confirming that their greatest concentration during autumn migration through Italy occurs at this island. In this species, all juveniles were seen migrating in flocks of adults. Finally, the passage of hundreds of Marsh Harriers Circus aeruginosus was reported, mostly over Pantelleria. Among adult harriers, it was possible to estimate the passage of birds belonging to different sex classes; unlike in the previous studies made in central, southern continental Italy and Malta during autumn migration, adult females outnumbered adult males (372 vs 298 individuals). Finally, considering the huge number of Accipitriformes observed, Pantelleria, so as Marettimo, should be enclosed among Important Bird Areas for the autumn migration of raptors in the Mediterranean basin.

Autumn migration of Marsh Harriers (Circus aeruginosus) across the Central Mediterranean in 2002 Observations on the autumn migration of the Marsh Harrier were made at two sites of the central Mediterranean: the Circeo promontory (central Italy) and the island of Malta. The aim was to investigate the passage of birds belonging to different sex and age classes. At the Circeo promontory a total of 787 individuals was counted, 37.5% of which were juveniles. Over the island of Malta the passage of 1535 Marsh Harriers was recorded with an evident peak comprising 906 birds on 13 September. At both sites males outnumbered females, mostly within the first half of September. Because, at least among adults, an imbalance towards females has been reported in the population wintering in central Europe, our results suggest that adult males could have a stronger tendency to migrate over a long distance, crossing the central Mediterranean area in large numbers. Whereas females, being larger than males, are able to tolerate colder temperatures and fast longer. Finally, our counts confirm the increase of the European population of the Marsh Harrier, which has occurred for the last three decades.