The adult Magellanic penguin spends the greater part of the year securing a mate and raising chicks. The adults arrive at the nesting sites in September where, if already part of a breeding pair, they engage in the repair of the nest. Otherwise, the adult penguins commence courtship behaviours (2) (5), which involve the male making a loud braying call to advertise for a mate. This is followed by walking in a circle around an interested female, and finally engaging in flipper patting, in which the male’s flippers are vigorously vibrated against the female’s body. Once formed, the breeding pairs are long-lasting and are maintained by behaviours such as mutual preening (5).
The nests of Magellanic penguins comprise either a simple scrape, often hidden under vegetation, or, where soil conditions permit, a burrow in soft soil or peat. The burrow may be up to one metre long and ends in a round chamber (5) (6).
After mating, a clutch of two eggs is usually laid, which are incubated by both adult birds, with each taking an initial long shift of just over two weeks, while the other forages in the ocean (5) (9). The foraging trips of the Magellanic penguin may be incredibly wide ranging, with some individuals tracked as far as 600 kilometres from the breeding colony (8). Towards the end of the 39 to 42 day incubation period, the incubation shifts become much shorter (2) (9).
Once hatched, the young Magellanic penguins are brooded for 24 to 29 days, during which time they grow a rudimentary layer of feathers that helps them to maintain their body temperature. The adults then leave the young unattended and only return to feed them every one to three days (5). During this time, the burrows provide better nesting grounds than surface nests, as they help protect against the wind and rain. However, they do on occasion become flooded, often resulting in the death of the chicks due to hypothermia (2).
After 40 to 70 days the chicks fledge, usually between January and March, and the adults moult their feathers in preparation for returning to the sea. The newly-fledged juveniles and adults then spend May to August following the northward movements of anchovies, their preferred prey. They will also take other fish, squid and crustaceans (4) (6) (10). The diet of the Magellanic penguin in the Falkland Islands is thought to contain a higher proportion of squid and crustaceans than elsewhere in its range (9).