Science Source

Consistent response of bird populations to climate change on two continents

States that large-scale analyses have generally focused on the impacts of climate change on the geographic ranges of species and on phenology, the timing of ecological phenomena
Uses long-term monitoring of the abundance of breeding birds across Europe and the United States to produce, for both regions, composite population indices for two groups of species: those for which climate suitability has been either improving or declining since 1980
Finds the ratio of these composite indices, the climate impact indicator (CII), reflects the divergent fates of species favored or disadvantaged by climate change and that the trend in CII is positive and similar in the two regions
Finds on both continents, interspecific and spatial variation in population abundance trends are well predicted by climate suitability trends