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The European honey buzzard Pernis apivorus is a summer visitor in Europe, wintering mostly in West-central Africa. Previous studies concerning timing of autumn migration in relation to sex groups provided contrasting results. In particular, a field survey made in southern Sweden did not report differences in timing, while a satellite study via GPS tracking on six adults, three males, and three females, revealed that the latter departed earlier. The aim of this 4-year study is to further investigate the timing of autumn migration in this species carrying out observations at the Strait of Messina, a bottleneck located along the Central Mediterranean flyway, between August 10th and September 30th 2016–2019. Adult European honey buzzards concentrated the passage between late August early September, with females passing on average 5 days earlier than males. It is suggested that a different role of sexes concerning exhibition of territorial displays during the late breeding season, would explain differences between sex groups in timing of both moult and autumn migration.

Capsule: Juvenile Short-toed Snake Eagles Circaetus gallicus hatching in the peripheral populations of Greece and Italy have limited opportunities for social learning of migration routes compared to those hatched elsewhere.Aims: To test the prediction that there would be a higher degree of migration synchrony between adult and juvenile Short-toed Snake Eagles originating from peripheral populations and using an extremely detoured flyway, when compared to other populations using a direct overland flyway.Methods: We use linear regression models to compare seasonal changes in the age distribution of migrating Short-toed Snake Eagles counted at two migration watch-sites in Italy (Arenzano) and Georgia (Batumi), along a detoured and a direct flyway, respectively.Results: Juveniles migrated a few days later than adults at both sites and the age ratios recorded at these two sites was similar. The daily proportion of juveniles increased along a similar slope during the migration season, thus showing a similar degree of synchrony between the age classes on both flyways.Conclusions: Contrary to our hypothesis, juvenile and adult migration is not more synchronized in peripheral populations using a detoured flyway compared to a core population using a direct migration flyway. Our results suggest that juveniles do not learn detours to complete trans-Mediterranean migration from their parents, but from other elders.

Migratory behavior of raptors is affected by several factors, including weather, geography, and topographical features. Here we provide information on how these factors may affect the behavior and detectability of the Short-toed Snake-Eagle (Circaetus gallicus). We observed passage of Short-toed Snake-Eagles at two watchsites along mountain chains in northeastern Greece (Mount Olympus) and northwestern Italy (Arenzano) during the peak periods of migration in autumn 2009 and spring 2010. More Short-toed Snake-Eagles were observed in spring than in autumn; this difference was more evident at Arenzano. Temperatures influenced the number of migrants observed. In particular, the number of individuals observed decreased drastically when temperatures were higher than 24°C during post-reproductive movements. At both sites, daily patterns showed a lower proportion of raptors observed during midday and early afternoon in autumn than in spring. These results suggest that, during autumn, individuals may pass...

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.

The predatory behaviour of captive wild kestrels was investiga ted to ascertain whether prolonged captivity, with no predation opportunities, could affect prey capture. Thirty kestrels were ob served. After a 48‐hour fast they were offered a live laboratory mouse. The behaviour before and after prey appearance, and la tency to predation were recorded. There was no difference in cap ture efficiency correlated with kestrel age, but adults performed preening significantly more often than young birds. Moreover, a clear inverse correlation was found between the latency of preening and of predation. Therefore, prolonged captivity associated with inactivity does not seem to exert a negative influence on predation in this species.