How Rockhopper Penguins Care for Their Chicks

The Two Eggs

• Rockhopper penguins lay two eggs about four to five days apart. The first egg is smaller than the second, and hatches after the second egg. The Rockhopper reproduction strategy is to give the second egg the best chance of surviving, expecting the first egg not to hatch or live to adulthood. This larger egg is brooded at the rear of the nest where it is more protected and experiences more stable temperatures.

Nesting Environments

• The nesting environment is another Rockhopper strategy for protecting their chicks. They make nests on sharp, rocky terrain that is difficult for predators to traverse. Generally, they are built on steep, high cliffs on the ocean. Rockhoppers nest in colonies that can contain thousands of nests. Although Rockhopper penguins are one of the smallest species, they are also the most aggressive, making it very difficult for an intruder to enter the colony.

Parental Shifts

• Both the male and female parents take responsibility for rearing the chicks. It generally takes 33 days for a Rockhopper egg to hatch, a period that's divided into three parental shifts. During the first part of the incubation both parents stand guard over the nest, followed by the male leaving to forage for a week or more. After he returns he stays on the nest until the eggs hatch while the female gathers food. Sometimes waiting parents have to go long periods without eating.

The Creche

• At about 25 days, the chicks have started to developed plumage and leave the nest to join the creche. The creche is a babysitting service where all the chicks are gathered in groups and watched by adults while both of their parents forage, which is often required to meet the chick's growing diet intake. Rockhopper penguins generally have many small creches scattered around the colony, compared with other penguin species that have one large creche.