Behavior

Penguin watching over sleeping chick
Andrew Shiva, CC BY 3.0, via Wikimedia Commons

Breeding

Penguins for the most part breed in large colonies, the exceptions being the yellow-eyed and Fiordland species; these colonies may range in size from as few as 100 pairs for gentoo penguins to several hundred thousand in the case of king, macaroni and chinstrap penguins. Living in colonies results in a high level of social interaction between birds, which has led to a large repertoire of visual as well as vocal displays in all penguin species. Agonistic displays are those intended to confront or drive off, or alternately appease and avoid conflict with, other individuals.

Penguins form monogamous pairs for a breeding season, though the rate the same pair recouples varies drastically. Most penguins lay two eggs in a clutch, although the two largest species, the emperor and the king penguins, lay only one. With the exception of the emperor penguin, where the male does it all, all penguins share the incubation duties. These incubation shifts can last days and even weeks as one member of the pair feeds at sea.

Penguins and Humans

Penguins have no special fear of humans and will often approach groups of people. This is probably because penguins have no land predators in Antarctica or the nearby offshore islands. They are preyed upon by other birds like skuas, especially in eggs and as fledglings. Other birds like petrels, sheathbills, and gulls also eat the chicks. Dogs preyed upon penguins while they were allowed in Antarctica during the age of early human exploration as sled dogs, but dogs have long since been banned from Antarctica. Instead, adult penguins are at risk at sea from predators such as sharks, orcas, and leopard seals. Typically, penguins do not approach closer than around 9 feet (2.7 meters), at which point they appear to become nervous.

Three penguins standing on rocks
Roux, CC BY-SA 3.0, via Wikimedia Commons