Additional observations of age‐dependent migration behaviour in western honey buzzards Pernis apivorus

Loop migration of adult European Honey Buzzards (Pernis apivorusLinnaeus, 1758) through the Central-Eastern Mediterranean

“…This phenomenon is called 'loop migration', and wind is one of the most important selective agents shaping this kind of strategy (Newton 2008;Klaassen et al 2010). In agreement with previous studies, juvenile European Honey Buzzards behave differently from adults, concentrating late in the season during autumn (Agostini & Logozzo 1995;Hake et al 2003;Agostini 2004) and being virtually absent during spring. Therefore, we will focus our discussion only on adult individuals.…”

Influence of Wind and Geography on Orientation Behavior of Adult Honey BuzzardsPernis apivorusDuring Migration Over Water

“…150 km wide (Fig. 1, Agostini & Logozzo 1997, Agostini et al 2000, Agostini 2004. A recent study, using satellite telemetry, showed that adult Honey Buzzards tend to compensate lateral winds during migration over land, leaving only a limited drift effect (Thorup et al 2003).…”

Analysis of the Spatial Migration Patterns of Adult Honey Buzzards (Pernis apivorus) During Spring and Autumn in the Central Mediterranean

“…In particular, during springs 2001-2002 a maximum of about 2000 Honey Buzzards were reported over Ustica (Panuccio et al 2004, Agostini et al 2005a Agostini 2005, Gustin et al 2005); thus migrants showed a high degree of synchronism at these two sites as can be expected from this species which is well known for the condensed migration period of adults with males and females reaching together their breeding areas (Cramp andSimmons 1980, Gensbøl 1992). During autumn migration adult Honey Buzzards cross the Central Mediterranean between the end of August and the first ten days of September (Agostini andLogozzo 1995, 1997). In this period their passage is less conspicuous: while an average number of 20 473 ± 1941 (SE) individuals was reported during springs 1996-2000 at the Strait of Messina (Corso 2001), on average 6714 ± 640 (SE) were counted at the same site during autumn 2002-2004(Panuccio et al 2005, Repaci and Morabito pers.…”

“…During autumn migration adult Honey Buzzards cross the Central Mediterranean between the end of August and the first ten days of September (Agostini andLogozzo 1995, 1997). In this period their passage is less conspicuous: while an average number of 20 473 ± 1941 (SE) individuals was reported during springs 1996-2000 at the Strait of Messina (Corso 2001), on average 6714 ± 640 (SE) were counted at the same site during autumn 2002-2004(Panuccio et al 2005, Repaci and Morabito pers. obs.).…”

“…They make a curvilinear migration over water applying true navigational abilities, Tunisia nearly always being out of sight. Unlike adults, large numbers of juvenile Honey Buzzards undertake sea crossings through the central Mediterranean during autumn migration, probably moving along NE-SW innate axis (Agostini 2004, Agostini et al 1999, Agostini et al 2002, Agostini et al 2004a. Since juveniles tend to migrate about two weeks later than adults during their first migration (Kjellén 1992, Agostini and Logozzo 1995) they probably move along innate directions of migration and, with some exception, they cannot learn the shortest route over sea to cross the Mediterranean by following adults (Agostini 2004, Agostini et al 1999, Agostini et al 2000, Agostini et al 2002, Agostini et al 2004a.…”