Challenging claims in the study of migratory birds and climate change

Endre Knudsen, Andreas Lindén, Christiaan Both, Niclas Jonzén, Francisco Pulido, Nicola Saino, William J. Sutherland, Lars A. Bach, Timothy Coppack, Torbjørn Ergon, Phillip Gienapp, Jennifer A. Gill, Oscar Gordo, Anders Hedenström, Esa Lehikoinen, Peter P. Marra, Anders P. Møller, Anna L. K. Nilsson, Guillaume Péron, Esa RantaDiego Rubolini, Tim H. Sparks, Fernando Spina, Colin E. Studds, Stein A. Saether, Piotr Tryjanowski, Nils Chr. Stenseth

Research output: Contribution to journalArticlepeer-review

302 Citations (Scopus)
6 Downloads (Pure)


Recent shifts in phenology in response to climate change are well established but often poorly understood. Many animals integrate climate change across a spatially and temporally dispersed annual life cycle, and effects are modulated by ecological interactions, evolutionary change and endogenous control mechanisms. Here we assess and discuss key statements emerging from the rapidly developing study of changing spring phenology in migratory birds. These well-studied organisms have been instrumental for understanding climate-change effects, but research is developing rapidly and there is a need to attack the big issues rather than risking affirmative science. Although we agree poorly on the support for most claims, agreement regarding the knowledge basis enables consensus regarding broad patterns and likely causes. Empirical data needed for disentangling mechanisms are still scarce, and consequences at a population level and on community composition remain unclear. With increasing knowledge, the overall support (‘consensus view’) for a claim increased and between-researcher variability in support (‘expert opinions') decreased, indicating the importance of assessing and communicating the knowledge basis. A proper integration across biological disciplines seems essential for the field's transition from affirming patterns to understanding mechanisms and making robust predictions regarding future consequences of shifting phenologies.
Original languageEnglish
Pages (from-to)928-946
Number of pages19
JournalBiological Reviews
Issue number4
Publication statusPublished - Nov 2011

Cite this