Page 13 - Panuccio2012
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Migration ecology of raptors in the Mediterranean
Figure 4 - Antikythira island, October 2009. the role of morphology is discussed to explain the
Results and discussion migratory behaviour of studied raptors (papers
IV, VII). In the case of short-toed snake eagles the
The role of morphology and energy consumption of energy during powered flapping
consumption rates flight is 8.7 times the energy used during soaring-
As mentioned above morphology plays a role of gliding flight (paper VII). This result may explain
paramount importance in determining raptor why short-toed snake eagles breeding in central-
flyways and behaviour. Among Accipitriformes, southern Greece do not cross the Mediterranean
different species show different rates of energy sea, preferring to migrate across the Bosporus
consumption as well as different skills in the both in autumn and spring. Similarly short-toed
exploitationofthermalcurrents.This heterogeneity, snake eagles breeding in Italy use a circuitous
due to species-specific and sex-specific differences flyway, crossing the Mediterranean at the Strait of
in morphology, leads to different migration Gibraltar. The role of morphology in relation to
strategies. Just to cite two opposite cases, harriers energy consumption is also discussed to explain
(Circus spp.) largely use powered flapping flight differences in the migration of juvenile honey
(Spaar and Bruderer 1997) and migrate on a broad buzzards and western marsh harriers in the Eastern
front over open sea, while lesser-spotted eagles Mediterranean (paper IV). The honey buzzards
(Aquila pomarina) concentrate at the Bosporus travel south-southwest during autumn migration
and Suez Straits to avoid having to fly over four and are strongly attracted by geographical features
different stretches of sea in the course of their such as peninsulas and islands, in an attempt to
migration: the Black Sea, the Marmara Sea, the reduce as much as possible their flight over sea. By
Mediterranean Sea and the Gulf of Suez (Meyburg contrast, western marsh harriers are less attracted
et al. 2001, 2002). Other species exist that exhibit by land masses, flying along approximately parallel
an intermediate behaviour. In this dissertation
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