Latitude‐specific responses of European birds' population growth rates to temperature and water availability

Climate limits distribution of species and shows considerable regional variability. However, studies relating climate variation to species population growth rates in different climatic zones while accounting for species' ecological traits are scarce. We assessed species population responses to the main climatic constraints at a continental scale by studying how precipitation and temperature at different latitudes influence interannual growth rates while considering species' life‐history traits. We gathered data on the abundance of 141 European breeding bird species from national breeding bird monitoring schemes in the Mediterranean (Catalonia, NE Spain), temperate (Czech Republic), and boreal (Sweden) climatic zones for the period 2002–2022. We related the interannual population growth rates of bird species to spring and winter temperature, water availability and heavy rainfall in the breeding season, considering migration strategy a key factor shaping bird responses to climate. We found general positive effects of spring and winter temperatures and water availability, and negative effects of heavy rainfall. Spring temperatures had increasingly more negative effect with migration distance. Long‐distance migrants responded negatively to temperatures in continental and northern Boreal zones. Increased spring temperatures affected residents more positively in southern Boreal than in continental and Mediterranean climatic zones. Higher water availability supported residents and short‐distance migrant populations more in lower and higher latitudes than in mid‐latitudes. Heavy rainfall tended to affect birds, especially residents, more negatively towards the north, where we revealed the strongest effect among the considered climate variables. Similarly, short‐distance migrants suffered more from the intensive rains in northern Boreal than in other climatic zones. Previously, temperature has been shown to be a strong climatic constraint of bird population dynamics. Our results suggest that future changes in precipitation regimes during the birds' breeding season should also be considered among the important climatic pressures on bird population growth rates in different climatic regions.