Spring has begun and the Arctic tern is once again embarking on its annual journey from the South Pole to its breeding grounds in Spitsbergen and the Netherlands. In a new study, we show that the route they follow is closely related to the climate. Wind plays a significant role, as does the distance and availability of food along the way.
Flight Routes of Migratory Birds
Migratory birds travel thousands of kilometers each year between their breeding and wintering grounds, consistently following certain flight routes. To understand these routes, climate science and ecology must be interconnected. Flight routes are not random; they are influenced by climate patterns.
Seabirds in the Atlantic and Pacific Oceans, for example, often follow a route shaped like the number 8: these provide strong and consistent tailwinds, allowing birds to travel faster and with less effort from A to B (see image 1). The routes also lead the birds past food-rich ocean areas to forage, storing energy for the further migration.
Can these flight routes be mimicked using climate data such as wind patterns and food availability? If so, we can use the findings to understand how these routes have developed, why birds choose them, and even how they may change in the future as the climate changes.