Little penguin

Name and taxonomy

Johann Reinhold Forster described the little penguin in 1781. The scientific name Eudyptula minor probably means the smaller good little diver. The common names all point at the blue of the back. The Maori call it korora, and that name is now used alongside the English one. The subspecies are still disputed, and several have been proposed.

Work on mitochondrial DNA in 2002 found two groups within the genus. One holds the birds of the North Island, Cook Strait and the Chatham Islands. The other holds the birds of Australia and of Otago in New Zealand. A study in 2016 named the Australian birds as a separate species. The IUCN still treats the two as one species with two distinct genetic groups. The white-flippered penguin of Banks Peninsula is counted as a subspecies or a colour form.

Evolution and relatives

The little penguin belongs to the Spheniscidae, the penguin family. Like every penguin, it has wings that work as flippers and cannot fly. It is the only living member of its genus in most treatments. Its nearest relatives on the site are probably the larger penguins of the far south. The Australian group reached Otago only between about 1500 and 1900. It moved in after people and their dogs cut back the New Zealand birds there.

The two groups differ in more than their genes. Australian birds carry brighter blue feathers than New Zealand ones. Their calls differ, and females prefer the local accent. Australian birds swim ashore in one large party after dark and walk up the beach together. That habit probably grew up against the marsupial hunters of Australia. Only the Australian birds lay a second clutch in a season.

Appearance

The head, back and upper flippers are indigo blue. Slate grey ear coverts fade into white on the chin, throat and belly. The bill is dark grey or black and measures 3 to 4 cm. The eyes are pale silver, blue-grey or hazel. The feet are pink above, with black soles and black webs. An adult stands 30 to 33 cm tall and weighs 1.1 to 1.2 kg.

The feathers hold dense packets of dark pigment. Those packets shed water and produce the blue colour of the bird. The sexes look alike, and only the bill separates them reliably. A male's bill averages 35.7 millimetres long, against 34.5 mm for a female. The flippers average 117.5 mm in both sexes. A young bird has a shorter, thinner bill and a brighter, lighter blue back.

Habitat and range

The species breeds around New Zealand and along the southern coast of Australia. Australian colonies run from Port Stephens in New South Wales west to Fremantle. Most sit on offshore islands, safe from foxes, dogs and people. Tasmania holds the largest Australian population, at 110,000 to 190,000 breeding pairs. Phillip Island in Victoria holds about 32,000 breeding adults. GBIF holds occurrence records from 12 countries and territories.

New Zealand colonies are smaller and more scattered than Australian ones. Some hold fewer than ten pairs. The broken coastline splits the birds into many small groups. Near Kaikoura, six or seven tiny colonies share less than 2% of the coast. Birds also nest in town, in cellars and foundations at Oamaru. Motunau Island holds 1,650 nests, the largest count in New Zealand.

A nest sits close to the sea, in sand, under vegetation or in a rock crevice. Birds also use caves, pipes, log piles, nest boxes and the space under a house. Some walk 1.5 kilometres inland and climb 300 metres to reach a site. Burrows usually sit more than 2 metres apart, and closer together inside a cave. Banding shows that individuals still travel far along the coast. A bird tagged at Gabo Island in Victoria was found dead in South Australia in 1984.

Diet and feeding

The little penguin chases small shoaling fish, squid and crustaceans under water. A two-year study of a Victorian colony found a diet of 76% fish and 24% squid. Nineteen fish species turned up, and pilchard and anchovy led the list. Most of the fish were under 10 cm long and many were young. New Zealand birds take arrow squid, slender sprat, red cod and ahuru. Krill, jellyfish, crab larvae, eels and seahorses appear in smaller amounts.

The bird feeds inshore rather than far out to sea. Data loggers show that half of all dives stop within 2 metres of the surface. The average dive lasts about 21 seconds. The deepest dive on record reached 66.7 metres and the longest lasted 90 seconds. While rearing chicks, a parent works within about 30 kilometres of the nest. Outside the breeding season a bird may travel up to 710 km.

Hunting style follows the prey. Birds hunt alone when the prey is large and taken one or two at a time. They hunt in groups when the prey is small and swims in shoals that can be surrounded. The Oamaru birds work in groups on sprat and gudgeon. Birds from Stewart and Codfish Islands hunt alone and eat mostly squid. Middle-aged adults range further from the nest and dive deeper than old ones.

Behaviour and social life

The little penguin is the most nocturnal of all penguins on land. It never visits a burrow in daylight. Moonlight and street lighting change the hour at which birds come ashore. They land in small parties rather than alone, which spreads the risk from predators. In good seasons a bird seeks out the same companions it left with that morning. Flippers drive the bird through water at up to 6 kilometres per hour.

Colonies are loose, and some pairs nest entirely on their own. Birds defend the burrow with a ladder of displays. A bird first stands upright with spread flippers and calls at an intruder 1 to 3 metres away. It then advances quickly with a braying call. Next comes light contact, a touch of bills or a slap with a flipper. A bird that will not retreat is bitten and beaten with the flippers.

Pairs preen each other, above all on the head, where a bird cannot reach itself. Preening removes parasites and strengthens the bond between the two birds. Each bird spreads a drop of oil from a gland above the tail onto every feather. That oil keeps the plumage waterproof. A moulting bird must stay ashore and lose condition, and some die soon afterwards.

Communication and senses

The colony is noisy through the night and quiet by day. Calls range from a low rumble to a sound like a trumpet. At the nest a bird gives a loud bray, and it finishes on an inhaled squeal. Deep growls carry a threat, and a short bark keeps contact at sea. Every bird has its own song. Parents and chicks use that song to tell family from stranger in the dark.

A male displays by standing tall with his flippers held back and his head to the sky. He then brays, alone or among a group of unpaired males. A female that accepts him joins a dance around the nest. The pair marches in small circles and brays as it goes. The calls of the Australian and New Zealand groups differ, and females favour the local pattern. Like other birds, the species uses sight, hearing, touch and chemical cues.

Reproduction and life cycle

Females are ready to breed at two years old and males at three. Males return to shore between June and August to dig or repair a burrow. They display at the entrance to attract a partner for the season. Pairs stay faithful through one season and often reunite in later years. The birds return to the same colony and often to the same burrow. The season shifts with the place, and eggs may appear from April to December.

A clutch holds one or two eggs, white or faintly speckled with brown, and three is rare. The eggs are laid one to four days apart and weigh about 55 grams each. Incubation takes up to 36 days, and both parents sit in turn. They swap duty every three or four days. Chicks hatch with down and are brooded for 18 to 38 days. After that the parents guard them only at night and hunt by day.

A chick flies the nest at 50 to 65 days old, weighing 800 to 1,150 grams. It reaches full independence between 57 and 78 days. Most birds first breed at three years old. Older parents raise more chicks, because experience improves the result. This is the only penguin that can raise more than one clutch in a season. A second brood at Oamaru raised breeding success by as much as 75%.

The average life is about 6 years by one measure and 6.5 by another. A banded bird was recaptured at 25 years and 8 months old. AnAge records one bird of at least 42.2 years. Food supply sets survival more than anything else. In April 1986 about 850 dead penguins washed ashore in western Victoria after the food failed.

Predators and threats

At sea the bird is taken by fur seals, sea lions, sharks, orcas and barracouta. Around Granite Island, roughly 40% of seal droppings held penguin remains. On land, tiger snakes and monitor lizards take chicks, and blue-tongued skinks take eggs. Gulls, skuas, currawongs and white-bellied sea eagles also kill penguins. Native predators alone do not threaten the species, because their diets are broad.

Introduced mammals do the real damage. Foxes, dogs, cats, rats, ferrets and stoats all raid colonies. A fox killed 53 penguins on Granite Island over a few nights in 1994. Middle Island near Warrnambool fell from about 600 birds in 2001 to under 10 in 2005. Tasmanian devils released on Maria Island in 2012 destroyed a colony of 3,000 pairs. A suspected stoat or ferret killed 29 penguins near Dunedin in November 2014.

Oil is the other great killer. It poisons a bird that swallows it and ruins the waterproofing of the plumage. The Iron Baron spill off Tasmania in 1995 was later estimated to have killed 25,000 penguins. The Rena grounding in New Zealand in 2011 killed about 2,000 seabirds directly. Nets drown birds, plastic blocks their stomachs, and boats strike them near the shore. In Perth, trauma from watercraft was the leading cause of death between 2003 and 2012.

Population and conservation

The IUCN Red List places the little penguin in Least Concern. The world total is put at about 1,000,000 birds, and it is falling. New Zealand classes the species as at risk and declining under its Wildlife Act. The New Zealand mainland population has dropped by 60 to 70% since the 1960s. iNaturalist holds 7,929 observations of the species.

Some Australian colonies have gone entirely. Granite Island fell from 1,548 birds in 2001 to 38 in 2013. A fox attack in 2020 cut it to 12 birds, and volunteers counted about 36 in 2025. The Manly colony in Sydney once numbered in the hundreds and now holds about 60 pairs. New South Wales listed that population as endangered in 1997.

Protection works where it is tried. Maremma sheepdogs guard Middle Island, and the colony climbed back to 100 birds by 2017. The first of those dogs, Oddball, gave her name to a film in 2015. A fence along 3.3 kilometres of a West Coast highway ended the roadkill after 2019. Dog-free zones, cat traps and nest boxes all help a colony hold its numbers. Victoria began vaccinating penguins against bird flu after a death at Phillip Island in 2026.

Relationship with humans

People once took little penguins for meat, skins and eggs. Shipwrecked sailors ate them, and the meat was soaked for days to soften it. Colonies were raided for skins, and a newspaper printed instructions for curing them in 1904. In the 20th century fishermen used the birds as bait for rock lobster pots. Others shot them for sport or killed them out of cruelty.

Attitudes turned in the second half of the 20th century. Breeding colonies are now managed for visitors and bring money to coastal towns. The nightly penguin parade at Phillip Island has drawn crowds since the 1920s. In 1987 more overseas visitors watched it than went to Uluru. About 500,000 tourists a year come to see the birds walk up the beach. Cameras and flash are banned there, because bright light frightens and blinds the birds.

Oiled birds are cleaned at rescue centres in Australia and New Zealand. Staff dress each arrival in a knitted jumper so that it cannot swallow the oil while preening. Phillip Island asked the public for 1,400 more jumpers in 2019. At the last big spill the centre cleaned 438 birds and 96% of them survived. Zoos in Australia, New Zealand and the United States keep the species in built enclosures.

In culture and myth

In Maori the bird is korora, and New Zealand agencies use that name beside the English one. Coastal towns in both countries treat the penguin as a local emblem. Oamaru built its tourism around the birds that nest under its old stone buildings. Victor Harbor still runs guided walks on Granite Island, though the colony has almost gone. Penny the Little Penguin was the mascot of the 2007 world swimming championships in Melbourne.

The species has an odd place in computing. A little penguin pecked Linus Torvalds on holiday in Australia. Reports say the bite led him to choose a penguin as the mascot of Linux. A programming exercise for the Linux kernel is named the Eudyptula Challenge. Its author writes under the name Little Penguin.

Australian film has taken up the bird as well. The story of the guard dog Oddball reached the screen in 2015. The dogs now on Middle Island were named Eudy and Tula after the genus. The knitted penguin jumper appears to have become a symbol of volunteer conservation. The birds appear on tourism posters across southern Australia and New Zealand.