Arctic birds migrate thousands of miles each year as they move between their breeding and wintering grounds. The Arctic Tern is especially well-known for its incredible annual journey – the recordholder for the longest round trip is a seven year-old female who flew 59,650 miles. Due to the extremely short breeding season, the millions of birds converging on the Arctic must raise their young in a brief, frantic window of opportunity when plants, insects and other prey are readily available.
It turns out birds have been nesting and raising young in the Arctic since their dinosaur relatives dominated the landscape.
Researchers combed through sediment collected from Alaska’s Prince Creek Formation, finding small Cretaceous fossils and fossil fragments which resemble the remains of modern gulls, geese, ducks, and loons. These adult and baby bird fossils, including perinatal remains (embryos and hatchlings) suggest that birds were breeding there and not just passing through. These 73 million year old fossils are the earliest known evidence of birds nesting in polar regions. As one study author noted: “Birds have existed for 150 million years. For half of the time they have existed, they have been nesting in the Arctic.”