Though a breeding bird of uplands in this country (which largely means the north and west), these small, speedy falcons disperse in winter, hitting the lowlands of the south and east, especially near the coast. The British population is boosted by birds from Iceland migrating to our relatively mild islands. Merlins are small and, for falcons, relatively short-winged and short-tailed, almost like very small Peregrines in shape. They are dashing and agile, pursuing passerines with twist and turns and pure speed. Only adult males are blue, and golden below, while juveniles and adult females are dull brown, with pale supercilia (‘eyebrows’).