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Zoological Studies 49(5): 651-656 (2010)

Local Weather Conditions Affect Migration Strategies of Adult Western
Honey Buzzards Pernis apivorus through an Isthmus Area

Michele Panuccio1,2, Nicolantonio Agostini1,2,*, Giuseppe Lucia1, Ugo Mellone1,3, Stephen Wilson1,
Jack Ashton-Booth1, Gianpasquale Chiatante1, and Simone Todisco1

1Mediterranean Raptor Migration Network (MEDRAPTORS), Via Mario Fioretti, Rome 18- 00152, Italy
2Dipartimento di Biologia Animale, Univ. of Pavia, Via Ferrata 1, Pavia 27100, Italy
3Current address: Grupo de Zoologia de Vertebrados/CIBIO, Univ. de Alicante, Apdo. correos 99, Alicante E-03080, Spain

(Accepted May 5, 2010)

Michele Panuccio, Nicolantonio Agostini, Giuseppe Lucia, Ugo Mellone, Stephen Wilson, Jack
Ashton-Booth, Gianpasquale Chiatante, and Simone Todisco (2010) Local weather conditions affect
migration strategies of adult Western Honey Buzzards Pernis apivorus through an isthmus area. Zoological
Studies 49(5): 651-656. We tested the effect of crosswinds, barometric pressure, and time of day on the
visible migration of adult Western Honey Buzzards Pernis apivorus through an isthmus area in southern
continental Italy. Simultaneous observations from 3 posts were made in autumn 2005 and 2006, and birds
were assigned to one of 3 local migration corridors: western, central, and eastern. During our observations,
prevailing winds were perpendicular to the direction of migration. The peak of migration occurred during the
afternoon and with westerly winds. Ideal weather conditions for soaring flight occurred during weak winds
and high barometric pressure. An analysis of migration frequencies among the 3 corridors suggests that adult
Western Honey Buzzards tend to compensate for deviations in lateral winds on a small scale when migrating
through this isthmus area. It appears that they do not slow their travel speed during weather conditions that
are unfavorable for soaring flight (strong lateral winds and low barometric pressure) by increasing the use of
powered flight. On the other hand, migrants will change their migration strategy in relation to wind drift when
migrating through the Channel of Sicily en route to Africa, thus showing a broad front of migration over water.
http://zoolstud.sinica.edu.tw/Journals/49.5/651.pdf

Key words: Western Honey Buzzard, Raptor migration, Wind drift, Central Mediterranean.

During migration, birds face a variety of of the most important factors triggering the onset
of soaring-bird migration (Shamoun-Baranes et
challenges including geographical complexity, al. 2003), and favorable winds can minimize both
competition during stopovers, and the variability the time and energy birds allocate to migration
and unpredictability of meteorological conditions (Houston 1998). General wind conditions
(Berthold 2001). In particular, weather conditions can shape the migratory routes of raptors; for
can affect flight behaviors and migration pathways example, Klaassen et al. (2010) demonstrated
on both large and small scales and ultimately a how crosswinds cause Western Marsh Harriers
bird’s decision when to depart (Alerstam 1979, Circus aeroginosus to partially drift thus promoting
Richardson 1990, Maransky et al. 1997, Danhardt a loop migration. The Western Honey Buzzard
and Lindstrom 2001, Shamoun-Baranes et al. Pernis apivorus is one of the most common raptor
2006, Agostini et al. 2005, Liechti 2006). In species recorded at migration hotspots in the
particular, sea-level pressure was shown to be one

*To whom correspondence and reprint requests should be addressed. E-mail:nicolantonioa@tiscalinet.it

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