Penguins, unlike other birds, are thickly and evenly covered with short, stiff feathers and have wings reduced to flippers for swimming. They are fast and agile swimmers, flightless, and confined to the Southern Hemisphere, with a circumpolar distribution almost entirely confined below 30° S. Of the world's 17 species, eight occur in New Zealand seas and the commonest of these around the coasts of the three main islands is the blue penguin, Eudyptula minor, known in Australia as the fairy penguin. There are two subspecies: the northern, which is found around the North Island and on the north and north-east coasts of the South Island, and the southern, which occurs on Stewart Island, on the south-eastern, southern, and western coasts of the South Island, and on the Chathams. Occasionally each race is found beyond these limits. The northern race is the one which is also native to southeastern Australia. Separation into subspecies depends upon minor colour differences, the northern bird being predominantly light-blue above and white below, the southern bird being dark-blue above. In both the bill is dark-brown, the eyes silver-grey, and the feet pale-pink. Males are slightly heavier than females and have a stouter and less-tapered bill.

Blue penguins occur in coastal waters and seldom wander far from their nesting areas. Daylight hours are spent at sea fishing; the only time that long periods are spent ashore is during the moult. The breeding season has its peak at times between August and November, depending upon the latitude – the further south the birds occur the later the peak occurs. Nests are usually made in natural holes or crevices, burrows, or even under buildings, and variable amounts of such nesting materials as dry grass, flax, seaweed, or sticks are used. The usual clutch size is two eggs. These are white and are incubated by both parents. The incubation time is between five and six weeks.

The call is a disyllabic wail or moan which starts on a low note and is repeated a number of times with the pitch rising throughout.

A closely related species, the white-flippered penguin, breeds on Banks Peninsula and may be found on the eastern coast of the South Island from Cook Strait to Otago Peninsula.

by Gordon Roy Williams, B.SC.(HONS.)(SYDNEY), Lecturer in Agricultural Zoology, Lincoln Agricultural College.