Effects of Spring Temperatures on the Strength of Selection on Timing of Reproduction in a Long-Distance Migratory Bird

• DOI: 10.1371/journal.pbio.1002120
• Publication Date: 2015-04-07T14:20:28Z
• Authors: Marcel E. Visser; Phillip Gienapp; Arild Husby; Michael Morrisey; Iván de la Hera; Francisco Pulido; Christiaan Both
• Keywords: Ficedula; Limiting

Climate change has differentially affected the timing of seasonal events for interacting trophic levels, and this often led to increased selection on timing. Yet, environmental variables driving have rarely been identified, limiting our ability predict future ecological impacts climate change. Using a dataset spanning 31 years from natural population pied flycatchers (Ficedula hypoleuca), we show that directional reproduction intensified in first two decades (1980-2000) but weakened during last decade (2001-2010). Against expectation, pattern could not be explained by temporal variation phenological mismatch with food abundance. We therefore explored an alternative hypothesis was conditions individuals experience when arriving spring at breeding grounds: early cold may reduce survival. First, female recruits, arrival date year correlates positively hatch date; hence, early-hatched colder than late-hatched individuals. Second, temperatures recruitment were high, young had higher probability low. interpret as potential cost years, warming reduced cost. thus recruits associated stronger these birds born. As beginning study increased, recently declined again, showed nonlinear demonstrate lag up can alter traits populations, something important implications understanding how patterns populations.