Habitat‐ and species‐mediated short‐ and long‐term distributional changes in waterbird abundance linked to variation in European winter weather

Abstract

Aim Many species are showing distribution shifts in response to environmental change. We explored (a) the effects of inter‐annual variation in winter weather conditions on non‐breeding distributional abundance of waterbirds exploiting different habitats (deep‐water, shallow water, farmland) and (b) the long‐term shift in the population centroid of these species and investigate its link to changes in weather conditions. Location Europe. Methods We fitted generalized additive mixed Models to a large‐scale, 24‐year dataset (1990–2013) describing the winter distributional abundance of 25 waterbird species. We calculated the annual and long‐term (3‐year periods) population centroid of each species and used the winter North Atlantic Oscillation (NAO) index to explain the inter‐annual and long‐term shifts in their location. Results (a) Year‐to‐year southwestwards shifts in the population centroids of deep‐ and shallow‐water species were linked to negative NAO values. Shallow‐water species shifted northeastwards associated with positive NAO values and the distance shifted increased with increasing NAO. Deep‐water species shifted northeastwards up to zero NAO indices, but showed no further increase at higher NAO values. (b) Deep‐water species showed long‐term northeastwards shifts in distributional abundance throughout the 1990s and the 2000s. Shallow‐water species, on the other hand, shifted northeastwards during the 1990s and early 2000s, but southwestwards thereafter. There were no significant links between the NAO and year‐to‐year movements or long‐term shifts in farmland species’ population centroid. Main Conclusions We provide evidence for a link between both year‐to‐year and long‐term changes in waterbird winter distributional abundances at large geographical scales to short‐ and long‐term changes in winter weather conditions. We also show that species using shallow water, deep‐water and farmland habitats responded differently, especially at high NAO values. As well as important ecological implications, these findings contribute to the development of future conservation measures for these species under current and future climate change.

Differential winter and breeding range shifts: Implications for avian migration distances

“…Our results are consistent with the pole‐ward shifts documented in North American birds during the winter (La Sorte & Thompson, ) and in Europe (Potvin et al, ; Visser et al, ). Our reaffirmation of northward winter shifts was therefore not surprising, as birds are known to be physiologically constrained by winter temperatures (Root, ) and temperature‐driven northward shifts of wintering birds have been widely documented (La Sorte & Thompson, ; Lehikoinen et al, ; Pavón‐Jordán et al, ). Although our finding that winter temperatures have declined at the stationary COAs appear to be at odds with the current global warming trends (United States Global Change Research Program, ), cooling trends in the south and south‐eastern United States have been documented since the 1950s.…”

“…Our results are consistent with the pole-ward shifts documented in North American birds during the winter (La Sorte & Thompson, 2007) and in Europe (Potvin et al, 2016;Visser et al, 2009). Our reaffirmation of northward winter shifts was therefore not surprising, as birds are known to be physiologically constrained by winter temperatures (Root, 1988) and temperature-driven northward shifts of wintering birds have been widely documented (La Sorte & Thompson, 2007;Lehikoinen et al, 2013;Pavón-Jordán et al, 2019).…”

“…Multidirectional shifts—shifts having a latitude and longitude component—can be evaluated by incorporating measures of central tendency of a species range. Using central tendency measures, multidirectional shifts have been documented in North America and Europe for various birds, trees and plant species (Ash, Givnish, & Waller, ; Currie & Venne, ; Fei et al, ; Huang, Sauer, & Dubayah, ; Pavón‐Jordán et al, 2019).…”

Changing Migratory Behaviors and Climatic Responsiveness in Birds

“…Thus, both NAO and SRI can be used as proxies of weather conditions encountered by wintering and migrating birds, so species' responses to year-to-year variability in NAO and SRI can be considered as measures of responsiveness to weather and, thereby, to climate change. Indeed, bird species have been shown to vary greatly in how much their migration timing and winter distribution are explained by NAO (Haest et al, 2018a;Pavón-Jordán et al, 2018) or by weather variables at wintering and stopover sites (Van Buskirk et al, 2012;Haest et al, 2018b). Although some of this interspecific variation may be due to methodological issues (Haest et al, 2018a), biological differences such as habitat type (Pavón-Jordán et al, 2018) and migration distance (Van Buskirk et al, 2012) may also cause different species to vary in weather responsiveness.…”

“…Indeed, bird species have been shown to vary greatly in how much their migration timing and winter distribution are explained by NAO (Haest et al, 2018a;Pavón-Jordán et al, 2018) or by weather variables at wintering and stopover sites (Van Buskirk et al, 2012;Haest et al, 2018b). Although some of this interspecific variation may be due to methodological issues (Haest et al, 2018a), biological differences such as habitat type (Pavón-Jordán et al, 2018) and migration distance (Van Buskirk et al, 2012) may also cause different species to vary in weather responsiveness. It remains unclear whether these differences explain why not all species have adjusted their migratory behaviors to the same extent over time as climate has been warming (Van Buskirk et al, 2012;Haest et al, 2018a,b;Pavón-Jordán et al, 2018).…”