Auteurs: Ondine Filippi-Codaccioni, Jean-Pierre Moussus, Jean-Paul Urcun, Frédéric Jiguet
Bron: JOURNAL OF ORNITHOLOGY, online DOI 10.1007/s10336-010-0500-5
Abstract: Evidences for phenological changes in response to climate change are now
numerous. One of the most documented changes has
been the advance of spring arrival dates in migratory birds. However,
the effects of climate change on subsequent events of
the annual cycle remain poorly studied and understood. Moreover, the
rare studies on autumn migration have mainly concerned
passerines. Here, we investigated whether raptor species have changed
their autumn migratory phenology during the past 30
years at one of the most important convergent points of western
European migration routes in France, the Organbidexka pass,
in the Western Pyrenees. Eight out of the 14 studied raptor species
showed significant phenological shifts during 1981–2008.
Long-distance migrants displayed stronger phenological responses than
short-distance migrants, and advanced their mean passage
dates significantly. As only some short-distance migrants were found to
delay their autumn migration and as their trends in
breeding and migrating numbers were not significantly negative, we were
not able to show any possible settling process of
raptor populations. Negative trends in numbers of migrating raptors
were found to be related to weaker phenological responses.
Further studies using data from other migration sites are necessary to
investigate eventual changes in migration routes and
possible settling process.
Bron: JOURNAL OF ORNITHOLOGY, online DOI 10.1007/s10336-010-0500-5
Abstract: Evidences for phenological changes in response to climate change are now
numerous. One of the most documented changes has
been the advance of spring arrival dates in migratory birds. However,
the effects of climate change on subsequent events of
the annual cycle remain poorly studied and understood. Moreover, the
rare studies on autumn migration have mainly concerned
passerines. Here, we investigated whether raptor species have changed
their autumn migratory phenology during the past 30
years at one of the most important convergent points of western
European migration routes in France, the Organbidexka pass,
in the Western Pyrenees. Eight out of the 14 studied raptor species
showed significant phenological shifts during 1981–2008.
Long-distance migrants displayed stronger phenological responses than
short-distance migrants, and advanced their mean passage
dates significantly. As only some short-distance migrants were found to
delay their autumn migration and as their trends in
breeding and migrating numbers were not significantly negative, we were
not able to show any possible settling process of
raptor populations. Negative trends in numbers of migrating raptors
were found to be related to weaker phenological responses.
Further studies using data from other migration sites are necessary to
investigate eventual changes in migration routes and
possible settling process.
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