Northeastwards Shifts of Waterbird Species’ Wintering Range in European Flyways

by Cortland Henderson

Several studies of bird range shifts have found northward shifts in wintering distributions. However, these studies have been limited by studying the limits of bird migrations, rather than distributions of whole ranges or populations. Research on European butterfly species has found southern boundary retraction in addition to northern boundary expansion, which calls for further examination of whole bird ranges in European flyways. Using survey data from nine countries over a three-decade period, Lehikoinen et al. (2013) track the centers of gravity of three common waterbird species in Europe to determine spatial shifts of entire ranges. They found that a 3.8 °C increase in early winter temperatures in northeastern sites of the European flyway has been linked to north-eastwards shifts in the entire wintering range of all three waterbird species. In addition to overall shifts, they detected that northern boundaries of bird ranges experienced higher rates of expansion than the rates of retraction of southern boundaries. For the first time at the larger flyway level, wintering distribution changes have been linked to rising temperatures. Continue reading