The smallest loon, with a slender neck and bill. Often holds the thin bill at an upward angle. In breeding plumage, note smooth gray head, brick-red throat, and dark back. In winter, dark cap and hind neck contrast with white face and throat. In flight, often lowers and raises head more than other loons; also note small feet. Juveniles can look quite dark with a smudgy gray neck and limited white throat. Often confused with other loons, especially Pacific and Arctic; note overall head and bill shape and less sharp contrast to the head pattern. Breeds on ponds in the Arctic tundra. Winters primarily on saltwater, but can use large lakes and reservoirs in migration. Sometimes gathers in loose flocks where food is plentiful.