Active European warzone impacts raptor migration

Human conflicts can have impacts on wildlife, from direct mortality and environmental damage to the displacement of people, changing institutional dynamics and altering economies.^1,2,3 Extreme anthropogenic disturbances related to conflict may act as a barrier to migrating birds and increase the energetic costs of migration.⁴ On February 24^th, 2022, the Russian Federation invaded Ukraine, with targeted attacks on Kyiv and the eastern regions.⁵ By March 3^rd, when the first of 19 tagged Greater Spotted Eagles entered Ukraine on migration, the conflict had spread to most major cities, including parts of western Ukraine.⁶ We quantified how conflict impacted the migratory behavior of this species using GPS tracks and conflict data from the Armed Conflict Location and Event Data (ACLED) project^7,8 in a quasi-experimental before-after control-impact design, accounting for meteorological conditions. Migrating eagles were exposed to conflict events along their migration through Ukraine and exhibited different behavior compared with previous years, using fewer stopover sites and making large route deviations. This delayed their arrival to the breeding grounds and likely increased the energetic cost of migration, with sublethal fitness effects. Our findings provide a rare window into how human conflicts affect animal behavior and highlight the potential impacts of exposure to conflict events or other extreme anthropogenic disturbances on wildlife.