Highly mobile insectivorous swifts perform multiple intra-tropical migrations to exploit an asynchronous African phenology

Research output: Contribution to journalArticle


With timely allocated movement phases, mobile organisms can match their space-use with the seasonality of the environment and thereby optimise their resource utilisation over time. Long-distance avian migrants are known to move with the seasonal dynamics on an annual basis, but how individuals respond to seasonality within their tropical non-breeding range has been less studied. Here we analyse the movement pattern of a highly mobile aerial insectivorous bird, the pallid swift Apus pallidus, and its association with the local habitat phenology during the non-breeding period, using individual-based light-level geolocation. We extracted timing and location of 21 birds’ residence periods, as well as characteristics of the intervening movements, such as distance and speed. We used time series of precipitation and vegetation data for each residence area to extract the timing of the local end of the rainy season and the onset of the dry season. The pallid swifts repeatedly upgraded their habitat by undertaking 2–5 intra-tropical migrations correlated with the withdrawal of the rains and the onset of the local dry season. The birds arrived to the sites on average 12 days after rains ended and departed about two weeks after the onset of dry season suggesting that the birds closely tracked a spatiotemporal window presumably timed with optimal foraging conditions. Our results provide insights in the ways Palaearctic–African migrants respond to the asynchronous phenology within their sub-Saharan non-breeding range. We confirmed that pallid swifts actively respond to deteriorating conditions by repeated upgrades in habitat quality, which likely have substantial consequences for an individual's access to an essential, spatiotemporally ephemeral food resource. However, the pallid swifts did not surf an apparent resource wave per se as would be expected in a highly mobile species, indicating that also other factors, such as spatial patchiness of resources, may influence the movement decision.


External organisations
  • The Swiss Ornithological Institute
  • Milan Natural History Museum
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Ecology


  • insectivorous bird, intra-tropical migration, phenology
Original languageEnglish
Publication statusE-pub ahead of print - 2018 Oct
Publication categoryResearch

Related projects

Niklas Larsson, Atticus Pinzon-Rodriguez, Arne Hegemann, Brianne Addison, Charlie Cornwallis, Giuseppe Bianco, INGRID SASSENHAGEN, Jerker Vinterstare, Julian Melgar, Julio Neto, Lasse Jakobsen, Mikael Ekvall, Mihaela Ilieva, Natalia Annenkova, Pallavi Chauhan, Sylvie Tesson, Yannis Vardanis, Catherine Tayleur, Emily Baird, Olle Lind, Jakob Löndahl, Tina Santl-Temkiv, Anders Hedenström, Åke Lindström, Anders Nilsson, Bengt Hansson, Dennis Hasselquist, Erik Svensson, Henrik Smith, Helena Westerdahl, Jan-Åke Nilsson, Johan Bäckman, Katarina Hedlund, Lars Råberg, Maria Ingimarsdottir, Martin Green, Maria Sandell, Martin Stjernman, Nils Kjellén, Ola Olsson, Rachel Muheim, Richard Ottvall, Staffan Bensch, Xiuhong Yang, Sara Snogerup-Linse, Heiner Linke, Mikkel Brydegaard Sorensen, Patrik Lundin, Sune Svanberg, Zuguang Guan, Ann-Sofie Albrekt, Anders Hargeby, Anders Persson, Christer Brönmark, Emma Kritzberg, Karin Rengefors, Lars-Anders Hansson, Olof Berglund, Wilhelm Granéli, Alice Nicolle, Ben Chapman, Christian Skov, Johan Ahlgren, Jakob Brodersen, Jessica von Einem, Kaj Hulthén, Kelly Gutseit, Karen Lebret, Lynn Ranåker, MATTIAS EKVALL, Mercy Lard, MIKAEL JÖNSSON, PER HALLGREN, Peter Ljungberg, Samuel Hylander, Tony Fagerberg, Therese Jephson, Tomas Johansson, Bjorn Canback, Bengt Danielsson, Christoffer Johansson, Emma Ådahl, Florian Muijres, Jörgen Ripa, Melissa Bowlin, Niclas Jonzén, Per Henningsson, Roger Härdling, Andreas Nord, Arzu Gursoy, Asghar Muhammad, Anna Nilsson, Anna Runemark, Barbara Tschirren, Cecilia Nilsson, Håkan Karlsson, Irene Pala, Juliana Dänhardt, Johan Nilsson, Jens Rydell, Jonas Waldenström, Keith Larson, Kristina Karlsson, Kristin Scherman, Mikael Åkesson, Martin Andersson, Maja Tarka, Maren Wellenreuther, Max Lundberg, Miriam Liedvogel, Maj Rundlöf, Martin Wintersparv Stervander, Machteld Verzijden, Olof Hellgren, Raymond Klaassen, Roine Strandberg, Susanne Åkesson, SANDRA SKÖLD CHIRIAC, Sophia Engel, Sissel Sjöberg, Sara Naurin, Thomas Alerstam, Tom J Evans, Torbjörn von Schantz, Ulf Ottosson, Marie Dacke & Helena Osvath


Project: Research

View all (1)