The chinstrap penguin (Pygoscelis antarcticus) is a species of penguin that inhabits a variety of islands and shores in the Southern Pacific and the Antarctic Oceans. Its name stems from the narrow black band under its head, which makes it appear as if it were wearing a black helmet, making it easy to identify. Other common names include ringed penguin, bearded penguin, and stonecracker penguin, due to its loud, harsh call.
The chinstrap penguin grows to a length of 68–76 cm and a weight of 3.2–5.3 kg, with the weight varying with the time of year. Males are greater in weight and height than females.
The adult chinstrap's flippers are black with a white edge; the inner sides of the flippers are white. The face is white extending behind the eyes, which are reddish brown; the chin and throat are white, as well, while the short bill is black. The strong legs and the webbed feet are pink. Its short, stumpy legs give it a distinct waddle when it walks. The chinstrap penguin's black back and white underside provide camouflage in the form of countershading when viewed from above or below, helping to avoid detection by its predators.