Linking events throughout the annual cycle in a migratory bird—non-breeding period buffers accumulation of carry-over effects
Annual cycles of animals consist of distinct life history phases linked in a unified sequence, and processes taking place in one season can influence an individual’s performance in subsequent seasons via carry-over effects. Here, using a long-distance migratory bird, the collared flycatcher Ficedula albicollis, we link events throughout the annual cycle by integrating breeding data, individual-based tracking, and stable-carbon isotopes to unravel the connections between different annual phases. To disentangle true carry-over effects from an individuals’ intrinsic quality, we experimentally manipulated the brood size of geolocator-tracked males prior to tracking. We did not find unambiguous differences in annual schedules between individuals of reduced and increased broods; however, in the following spring, the latter crossed the Sahara and arrived at the breeding grounds earlier. Individuals with higher absolute parental investment delayed their autumn migration, had shorter non-breeding residency period but advanced spring migration compared to individuals with lower breeding effort. Neither the local non-breeding conditions (as inferred from δ13C values) nor the previous breeding effort was linked to the timing of the following breeding period. Furthermore, while on migration, collared flycatchers showed a pronounced “domino effect” but it did not carry over across different migration seasons. Thus, the non-breeding period buffered further accumulation of carry-over effects from the previous breeding season and autumn migration. Our results demonstrate tight links between spatially and temporally distinct phases of the annual cycles of migrants which can have significant implications for population dynamics.
Timing is everything! This holds true also for migratory animals which must time their annual movements, breeding and non-breeding seasons according to the environment they live in. However, perfect timing of a particular event can be hampered by past events. We studied connections between spatially and temporarily distinct annual phases in collared flycatchers, a small bodied bird which twice a year migrates between Europe and sub-Saharan Africa. We found tight links between individual’s parental investment and timing of autumn migration, but not spring migration. Similarly, the timing of autumn migration did not translate to influence the timing of spring migration. Thus, our results demonstrate that the non-breeding period may serve as a buffer to overcome high energy expenditure during the previous breeding season and prevent further accumulation of carry-over effects in migratory birds.
KeywordsAutumn migration Geolocator Phenology Spring migration Seasonal interactions Stable isotope
We thank R. Dzuro, A. Edme, A. Höchsmannová, T. Koutný, L. Pietrement, H. Ringlová, J. Spurná, J. Stříteský, S. Vikmane, B. Vyroubalová, M. Zemánek and P. Zobač for their help in the field. S. Hahn assisted with geolocator data analyses. D. Hanley and J. Cuthbert helped with language editing and two anonymous reviewers provided helpful comments on an earlier version of the manuscript.
This study was funded by the Czech Science Foundation (grant number: 13-06451S to PA).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
This study was carried out in accordance with the Ethical Committee of Palacký University and approved by the Ministry of Education, Youth and Sports of the Czech Republic (Licence number: MSMT-56147/2012-310). All applicable institutional and national guidelines for the care and use of animals were followed.
- Adamík P, Emmenegger T, Briedis M, Gustafsson L, Henshaw I, Krist M, Laaksonen T, Liechti F, Procházka P, Salewski V, Hahn S (2016) Barrier crossing in small avian migrants: individual tracking reveals prolonged nocturnal flights into the day as a common migratory strategy. Sci Rep 6:21560. https://doi.org/10.1038/srep21560 CrossRefPubMedPubMedCentralGoogle Scholar
- Cramp S, Perrins CM (1993) Handbook of the birds of Europe, the Middle East and Africa. The birds of the western Palearctic, vol. VII. Flycatchers to shrikes. Oxford University Press, Oxford, UKGoogle Scholar
- López-Calderón C, Hobson KA, Marzal A, Balbontín J, Reviriego M, Magallanes S, García-Longoria L, de Lope F, Møller AP (2017) Environmental conditions during winter predict age- and sex-specific differences in reproductive success of a trans-Saharan migratory bird. Sci Rep 7:18082. https://doi.org/10.1038/s41598-017-18497-2 CrossRefPubMedPubMedCentralGoogle Scholar
- Piersma T (1987) Hop, skip, or jump? Constraints on migration of Arctic waders by feeding, fattening, and flight speed. Limosa 60:185–194Google Scholar
- Stresemann E, Stresemann V (1966) Die Mauser der Vögel. J Ornithol 107:1–448Google Scholar
- Svensson L (1992) Identification guide to European passerines, 4th, revised and enlarged edn. StockholmGoogle Scholar