Population Growth in a Wild Bird Is Buffered Against Phenological Mismatch

• Published in: Science (American Association for the Advancement of Science) Vol. 340; no. 6131; pp. 488 - 491
• Main Authors: Reed, Thomas E., Grøtan, Vidar, Jenouvrier, Stephanie, Sæther, Bernt-Erik, Visser, Marcel E.
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 26.04.2013; The American Association for the Advancement of Science; American Association for the Advancement of Science (AAAS)
• Subjects: Animal and plant ecology; Animal populations; Animal, plant and microbial ecology; Animals; Availability; Aves; Biological and medical sciences; Birds; Breeding; Buffers; Climate; Climate Change; Climatic conditions; Climatology. Bioclimatology. Climate change; Communities; Computer Simulation; Concerts; Demecology; Directional selection; Earth, ocean, space; Ecological competition; Environmental changes; Environmental Sciences; Exact sciences and technology; External geophysics; Female; Female animals; Fitness; Food availability; Foods; Fundamental and applied biological sciences. Psychology; Genetic Fitness; Life cycles; Life history; Meteorology; Models, Biological; Natural populations; Passeriformes - genetics; Passeriformes - physiology; Phenology; Population decline; Population dynamics; Population Growth; Reduction; Selection, Genetic; Simulations; Vertebrata; wild birds; Dynamical climatology; Climate change; Vertebrata; Population growth; Sensitivity resistance; Phenology; Aves; Fitness
• ISSN: 0036-8075; 1095-9203; 1095-9203
• DOI: 10.1126/science.1232870

Broad-scale environmental changes are altering patterns of natural selection in the wild, but few empirical studies have quantified the demographic cost of sustained directional selection in response to these changes. We tested whether population growth in a wild bird is negatively affected by climate change-induced phenological mismatch, using almost four decades of individual-level life-history data from a great tit population. In this population, warmer springs have generated a mismatch between the annual breeding time and the seasonal food peak, intensifying directional selection for earlier laying dates. Interannual variation in population mismatch has not, however, affected population growth. We demonstrated a mechanism contributing to this uncoupling, whereby fitness losses associated with mismatch are counteracted by fitness gains due to relaxed competition. These findings imply that natural populations may be able to tolerate considerable maladaptation driven by shifting climatic conditions without undergoing immediate declines.