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Southbound direction of colonization of Short-toed Snake Eagle
was breeding in areas of southern continental Italy expected that migratory populations may follow
and Sicily at least until the end of the XIX century their historical expansion route (Salewski &
(Salvadori 1872, Lucifero 1898, Arrigone degli Bruderer 2007), while the southernmost direction
Oddi 1929) while actual data show its absence of colonization of Italy performed by Short-
and thus lack of re-colonization probably due to toed Snake Eagle turns out that birds facing a
the distance from the bulk of the metapopulation natural barrier show the capacity to interact with
system. In this scenario, we predict that this trend geography in shaping unexpected migratory and
will lead to lower occupancy in the next future in colonization directions.
southern Italy despite the availability of suitable Acknowledgments: we wish to thank Massimo
areas for this species. Campora, Guido Cattaneo and Paolo Forconi for
In conclusion the direction of migration is the their help in providing data of Short-toed Snake
result of natural selection, for this reason it is likely Eagles presence.
that only migration routes leading to survival
areas are favored by selection. For this reason it is
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