| Abstract | Abstract
Background
Understanding which intrinsic and extrinsic factors dictate decision-making processes such as leaving the natal area or not (migratory vs resident strategy), departure time, and non-breeding destination are key-issues in movement ecology. This is particularly relevant for a partially migratory meta-population in which only some individuals migrate.
Methods
We investigated these decision making-processes for 40 juvenile greater flamingos Phoenicopterus roseus fledged in three Mediterranean colonies and equipped with GPS-GSM devices.
Results
Contrary to the body size and the dominance hypotheses, juveniles in better body condition were more likely to migrate than those in worse conditions, which opted for a residence strategy. Flamingo probability of departure was not associated with an increase in local wind intensity, but rather with the presence of tailwinds with departure limited to night-time mostly when the wind direction aligned with the migratory destination. Moreover, a positive interaction between tailwind speed and migration distance suggested that juveniles opted for stronger winds when initiating long-distance journeys. In contrast to previous studies, the prevailing seasonal winds were only partially aligned with the migratory destination, suggesting that other factors (e.g., adults experience in mix-aged flocks, availability of suitable foraging areas en route, density-dependence processes) may be responsible for the distribution observed at the end of the first migratory movement. We found potential evidence of sex-biased timing of migration with females departing on average 10 days later and flying ca. 10 km/h faster than males. Female flight speed, but not male one, was positively influenced by tailwinds, a pattern most likely explained by sexual differences in mechanical power requirements for flight (males being ca. 20% larger than females). Furthermore, juveniles considerably reduced their flight speeds after 400 km from departure, highlighting a physiological threshold, potentially linked to mortality risks when performing long-distance non-stop movements.
Conclusion
These results suggest that not only intrinsic factors such as individual conditions and sex, but also extrinsic factors like weather, play critical roles in triggering migratory behaviour in a partially migratory metapopulation. Furthermore, social factors, including conspecific experience, should be taken into consideration when evaluating the adaptive processes underlying migration phenology, flight performance, and final destination selection. |
| Text | 485793 2023 orientation and navigation partial migration Migration phenology wetland movement ecology flight speed wind Weather, sex and body condition affect post fledging migration behaviour of the greater flamingo Phoenicopterus roseus Davide Scridel, Simone Pirrello, Simona Imperio, Jacopo G. Cecere, Giuseppe Albanese, Alessandro Andreotti, Giovanni Arveda, Fabrizio Borghesi, Giuseppe La Gioia, Luisanna Massa, Chiara Mengoni, Pierfrancesco Micheloni, Nadia Mucci, Riccardo Nardelli, Sergio Nissardi, Stefano Volponi, Carla Zucca Lorenzo Serra Area Avifauna Migratrice BIO AVM , Istituto Superiore per la Protezione e la Ricerca Ambientale ISPRA , via Ca Fornacetta 9, 40064, Ozzano dell Emilia, BO, Italy Davide Scridel, Simone Pirrello, Simona Imperio, Jacopo G. Cecere, Alessandro Andreotti, Pierfrancesco Micheloni, Riccardo Nardelli Lorenzo Serra CNR IRSA National Research Council Water Research Institute, via del Mulino 19, 20861, Brugherio, MB, Italy Davide Scridel Department of Life Sciences, University of Trieste, 34127, Trieste, TS, Italy Davide Scridel Manfredonia, FG, Italy Giuseppe Albanese Comacchio, FE, Italy Giovanni Arveda Servizio Tutela Ambiente e Territorio, Ufficio Zone Naturali, Comune di Ravenna, via Berlinguer 30, 48121, Ravenna, RA, Italy Fabrizio Borghesi Associazione Ornitologia Mediterranea, via Saponaro 7, 73100, Lecce, LE, Italy Giuseppe La Gioia Parco Naturale Regionale Molentargius Saline, via La Palma n 9, 09126, Cagliari, CA, Italy Luisanna Massa Area per la Genetica della Conservazione BIO CGE , Istituto Superiore per la Protezione e la Ricerca. Ambientale ISPRA , via Ca Fornacetta 9, 40064, Ozzano dell Emilia, BO, Italy Chiara Mengoni Nadia Mucci Anthus s.n.c., via Luigi Canepa 22, 09129, Cagliari, CA, Italy Sergio Nissardi Carla Zucca Area per i pareri tecnici e per le strategie di conservazione e gestione del patrimonio faunistico nazionale BIO CFN , Istituto Superiore per la Protezione e la Ricerca Ambientale ISPRA , via Ca Fornacetta 9, 40064, Ozzano dell Emilia, BO, Italy Stefano Volponi Abstract Background Understanding which intrinsic and extrinsic factors dictate decision making processes such as leaving the natal area or not migratory vs resident strategy , departure time, and non breeding destination are key issues in movement ecology. This is particularly relevant for a partially migratory meta population in which only some individuals migrate. Methods We investigated these decision making processes for 40 juvenile greater flamingos Phoenicopterus roseus fledged in three Mediterranean colonies and equipped with GPS GSM devices. Results Contrary to the body size and the dominance hypotheses, juveniles in better body condition were more likely to migrate than those in worse conditions, which opted for a residence strategy. Flamingo probability of departure was not associated with an increase in local wind intensity, but rather with the presence of tailwinds with departure limited to night time mostly when the wind direction aligned with the migratory destination. Moreover, a positive interaction between tailwind speed and migration distance suggested that juveniles opted for stronger winds when initiating long distance journeys. In contrast to previous studies, the prevailing seasonal winds were only partially aligned with the migratory destination, suggesting that other factors e.g., adults experience in mix aged flocks, availability of suitable foraging areas en route, density dependence processes may be responsible for the distribution observed at the end of the first migratory movement. We found potential evidence of sex biased timing of migration with females departing on average 10 days later and flying ca. 10 km/h faster than males. Female flight speed, but not male one, was positively influenced by tailwinds, a pattern most likely explained by sexual differences in mechanical power requirements for flight males being ca. 20% larger than females . Furthermore, juveniles considerably reduced their flight speeds after 400 km from departure, highlighting a physiological threshold, potentially linked to mortality risks when performing long distance non stop movements. Conclusion These results suggest that not only intrinsic factors such as individual conditions and sex, but also extrinsic factors like weather, play critical roles in triggering migratory behaviour in a partially migratory metapopulation. Furthermore, social factors, including conspecific experience, should be taken into consideration when evaluating the adaptive processes underlying migration phenology, flight performance, and final destination selection. Published version http //dx.doi.org/10.1186/s40462 023 00409 x Weather, sex and body condition affect post fledging migration behaviour of the greater flamingo Phoenicopterus roseus s40462 023 00409 x.pdf Articolo in rivista BioMed Central 2051 3933 Movement ecology Movement ecology Movement ecology Mov. ecol. DESCROVI EMILIANO davidescridel SCRIDEL DAVIDE |
