Data from: Changes in breeding phenology and population size of birds

1. Although the phenology of numerous organisms has advanced significantly in response to recent climate change, the life history and population consequences of earlier reproduction remain poorly understood. 2. We analyzed extensive data on temporal change in laying date and clutch size of birds from Europe and North America to test whether these changes were related to recent trends in population size. 3. Across studies, laying date advanced significantly while clutch size did not change. However, within populations, change in laying date and change in clutch size were positively correlated, implying that species that advanced their laying date the most were also those that increased their clutch size the most. 4. Greater advances in laying date were associated with species that had multiple broods per season, lived in non-agricultural habitats and were herbivorous or predatory. The duration of the breeding season increased for multi-brooded species and decreased for single-brooded species. In contrast to studies of changes in spring arrival dates (for migratory species), the changes we found in laying date and clutch size were not related to changes in population size (for resident or migratory species). 5. This suggests that, across a wide variety of species, mismatches in the timing of egg-laying or numbers of offspring have had relatively little influence on population size compared with other aspects of phenology and life history.LaydateCS_12Mar13.xlsxExcel file with data on changing phenology and population size of birds (N= 196 studies). Variables are explained and sources given in the sheet titled "Variables & Sources"LaydateYr_23Jan13.txtData file for mcmcGLMM in R. Note that slightly different data files were used for different analyses. This file was used for the analyses of laying date change per year in Table 4 of the paper.Tree29Dec12g.nexNexus tree file for mcmcGLMM analyses in R. This tree was used with the data file "LaydateYr_23Jan13.txt" to conduct the analyses shown in Table 4 of the paper. Note that slightly different trees were used for some other analyses. The g in the file name indicates that we used Grafen's method to construct branch lengths. There are 172 studies in the file; multiple studies of the same species were coded as A, B, C, etc. in the phylogenyFig 2 Pop models_16Sep13.xlsExcel worksheets with population models shown in Fig. 2 of the paper. Details of each model are given in the individual worksheets