The crested penguin is a carnivorous animal, that like all other penguin species, survives on a diet that is only comprised of marine animals. Squid and small crustaceans make up the bulk of the crested penguin's diet along with smaller organisms including krill and various species of fish.
The crested penguin is usually found nesting in the forests and scrub that line the New Zealand coast and although historically undisturbed, the crested penguin now has a number of land-dwelling predators including cats, dogs and foxes along with rats and weasels that hunt their eggs. Large seals including fur seals and leopard seals hunt the crested penguin in the water along with large sharks and killer whales.
On average, the crested penguin breeds once a year, forming pairs that usually remain faithful to one another. The female crested penguin lays two eggs in her nest in the forest which are incubated by both parents for up to a couple of months, when only one of the eggs will usually hatch. The crested penguin chicks are fed and kept warm by their parents and remain with them until the chicks are more than a few months old and are able to hunt for themselves.
Today, the crested penguin is listed as an endangered animal with an estimated wild population of less than 3,000 breeding pairs. The crested penguin populations have declined rapidly in their native habitats due to deforestation and the introduction of mammalian predators.