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218 THE RING 27, 2 (2005)
dency to undertake water crossing during spring migration? On the base of the age
of just six adult birds recovered in the central Mediterranean region during autumn
migration, much lower than of adults recovered along the western and the eastern
détour (Gibraltar and Bosporus), Schmid (2000) suggested that mostly less experi-
enced individuals use the central Mediterranean route. In particular, the author
concluded that with increasing age these birds will learn the more favourable but
longer détours via Gibraltar and Bosporus. According to Schmids hypothesis adults
migrating in the central Mediterranean region during spring should be funnelled to-
wards the Strait of Messina by their reluctance to cross the sea. However, since part
of adults move towards the Strait of Messina while many others cross the Tyrrhe-
nian Sea, are there among them individuals inexperienced to different degree? Are
adults moving across the Strait of Messina, among inexperienced birds, more expe-
rienced than those moving across the Tyrrhenian Sea? Moreover, why do not large
numbers of inexperienced individuals cross the Tyrrhenian Sea during autumn mi-
gration like juvenile birds? Since high degree of synchronization was found in the
spring passage of adults using different paths it is unlikely that a clear segregation
of thousands of raptors having different degrees of experience (inexperience?) oc-
curs at the same time in the same area. Furthermore, during the crossing of the
Channel of Sicily, how can inexperienced birds know the shortest flyway over water
between Pantelleria and the Cap Bon Peninsula (Agostini et al. 2005b, Fig. 1)? Dur-
ing observations made at the Strait of Messina between 25 April and 31 May 2004,
only a minority of birds with juvenile characteristics concerning plumage, cere
and/or iris presumably younger individuals were reported (Panuccio and
Agostini 2006). They migrated late in the season, mostly during the last ten days of
May. Over Panarea, only five birds showing juvenile characteristics were observed
between 25 April and 13 May 2004 (Agostini pers. obs.). In this regard, it is interest-
ing to note that a late spring passage of non adult birds was also reported in Is-
rael, thus along the eastern détour (Shirihai et al. 2000). In this picture, differently
from Schmid (2000), we suggest that during spring migration higher numbers of
adult Honey Buzzards breeding in east-central Europe, choose to cross the central
Mediterranean region perhaps using a more direct path between wintering and
breeding range. Moreover, as they reach this Mediterranean area, they make fur-
ther decisions choosing among alternative flyways. Besides atmospheric conditions
(Agostini et al. 2005a), the location of their breeding areas could also play a role in
their decision (crossing or not the Tyrrhenian Sea): birds breeding in the southern-
most European range may be less reluctant to cross the sea being at the end of their
migration and flying in large numbers over wide water surfaces (see also Agostini et
al. 2003). The observation of large numbers of Honey Buzzards seen undertaking
further sea crossings between the Italian Peninsula and ex-Yugoslavia and Albania
is consistent with this hypothesis (Gustin and Sorace 2004, Premuda et al. 2004). In
conclusion, during spring birds could be strongly motivated by the approaching re-
production season to use more direct flyways to reach earlier their breeding areas in
Europe, some of them flying over the sea also during the night (Agostini et al.
