The Snares crested penguin only breeds on the small (total of 341 ha) Snares Islands. The islands are mostly covered in mostly covered in a forest of the tree daisies Olearia lyalli and Brachyglottis stewartiae. The penguins nest in dense colonies of up to 1500 pairs, usually with part of the colony under vegetation. Snares penguins can often be seen roosting on branches overhanging the colony, sometimes up to 2m off the ground.The population is currently (2000 breeding season) estimated to be 30,000 breeding pairs. Read an account of the last census.
The males return to the breeding sites in August and construct a mound and bowl from earth, sticks, stones and lined with vegetation. The female follows shortly after and two eggs are laid in late September to early October, the larger "B" egg being laid 4.5 days after the smaller "A" egg. As with most crested penguins, both chicks are seldom raised successfully, many pairs lose an egg during incubation and should two eggs hatch, one chick usually dies before the end of the guard stage. About 10 days after egg laying the males go to sea for around 12 days, leaving the females to incubate the eggs. At this point the males have been ashore and fasting for six weeks. Once they return, the females break their 39 day fast and to go to sea for 10 days. Once the chicks hatch, the male continues to incubate and guard the chicks while the female forages and returns daily to feed the chicks. Once the chicks reach 3 weeks of age both parents forage and return daily to feed the chicks. At this stage the chick wanders, creching with other chicks if they are nearby, but returning to the nest to be fed.The chicks fledge at 11 weeks and the age of first breeding is thought to be about 6 years. Juveniles often straggle to the east coast of the South Island, usually to moult.
Snares penguins feed on euphausids (shrimp like crustaceans), cephalapods (squid and octopus) and fish. Little is known about where Snares penguins feed, but more reasearch is planned this year. Read about research into Snares penguin foraging ecology.
Predators of adult Snares Penguins are sea lions and leopard seals. Their eggs and chicks are hunted by skuas and petrels.