By Annie Hill
The original article in Russell Lights | Ngā Mārama o Kororāreka, January 2026 edition
Our town of Russell was originally named for these little birds: Kororāreka, means ‘sweet penguin’ and while, regrettably, this is a culinary reference, if any penguin could be described as ‘sweet’ it would be the Kororā Little Blue penguin, commonly found around our coasts and islands. Their scientific name Eudyptula minor means ‘good little diver and they are excellent pursuit hunters. Kororā are the smallest penguins in the world, and are found in both Aotearoa New Zealand and Australia. The English name comes from their slate-blue plumage: the melanosomes (as in melanin) in their feathers both colour and waterproof them. The penguins we know today, evolved around 8 million years ago from much larger birds, which became increasingly specialised to an aquatic life. Fossils of these mega penguins have been found in Aotearoa.
Kororā are distributed around the main motu as well as offshore islands, from the Three Kings to the Snares Islands. They breed mainly on islands in the Hauraki Gulf, around Cook Strait, the West Coast, Fiordland, Motunau Island, Banks Peninsula, Oamaru, Otago Peninsula, Foveaux Strait and Stewart and the Chatham Islands. They’re locally common along most of our coastlines, especially offshore islands, which provide protection from marine predators and disturbance, or where conservation efforts are made on the mainland. The largest colony of 1,650 nests is on Motunau Island. Officially, their conservation status is ‘least concern’, despite the fact that the mainland population has declined by 60-70%, since the 1960s. From personal observation, there are far fewer around the Bay of Islands than there were 15 years ago.
Because kororā are small, and sea-coloured, they’re generally heard ‘barking’ to one another at sea, before they’re seen. A retired skipper of the Fuller’s Cream Trip, told me that he used to amuse his passengers by mimicking a kororā, and that several used to swim over to answer him. At nesting sites, the main call is a loud bray ending in an inhalant squeal; they also make deep growls, similar to other penguins.
Kororā have white underparts – a common colouration for sea birds, helping them blend in from predators from below, while their blue backs hide them from above. Their flippers, wings which have evolved purely for swimming, are relatively short. The dark grey, hooked bill is sturdy and they have grey or hazel eyes and pinkish legs and feet. Males are slightly darker and have a more robust bill. Recently fledged young have bright blue backs and are considerably smaller. Kororā typically grow 30 to 33 cm tall and weigh1.5 kg, on average. They can live up to 25 years, but their average lifespan is about 6½ years.
During the breeding season, kororā forage within 20 km of the colony, usually in less than 50 m depth. They generally eat small shoaling fish, squid and crustaceans and fish singly or in small groups. Kororā only travel on land at night and the same group will wait offshore in rafts until it gets dark, before travelling to the nest site. They’re forced to stay ashore for the two weeks of their annual moult (between January and March), because all their feathers are replaced simultaneously.
Sometimes breeding as isolated pairs, kororā, also form colonies. Nests are situated in a wide variety of locations, from a small, lined scrape in a cave, to a deep burrow excavated by them or another species. Sites include rock crevices, under logs, in or under a variety of man-made structures, including nest boxes; pipes, stacks of wood or timber, and buildings, depending on what’s available. Their noise makes them unpopular with some people, and nesting near human habitation makes them easy prey for dogs. By choice, nests are close to the sea, but considering the size of the bird and its awkwardness on land, they occasionally travel prodigious distances of 1.5 km or more, to their nest.
Kororā are essentially monogamous and pairs often return year after year to the same site. They share incubation and rearing the chicks, taking it in turns to go to sea and feed. Although they’re the only species of penguin which can produce more than one clutch of eggs per season, few of them do so, apart from on the Otago peninsula and Kaikoura (and Australia). The 1-2 eggs are laid from July to mid-November; second (or even third) clutches might be laid as late as December, so that the breeding season can last into February. Double brooding can be strongly influenced by sea surface temperature as well, unsurprisingly, as food availability and age: pairs double brooding are most commonly long-established pairs who reclaimed successful nests.
Incubation takes up to 36 days and chicks are brooded for 18-38 days, fledging after 7-8 weeks, when they go to sea for the first time. Although some may leave the nest during this period, most will remain with their parents before becoming fully independent a few weeks later. They reach sexual maturity at three years.
It’s not only Māori who consider kororā to be good eating; they’re also preyed upon by fur seals, orca and sharks at sea, while ashore, eggs and chicks are taken by skuas and gulls. However, many colonies have been ravaged by introduced predators such as cats, dogs and ferrets, which can have sudden and severe impacts on penguin colonies and may kill many individuals in one night. At sea, kororā can get tangled in nets, while colonies ashore are also affected by human encroachment onto important breeding areas, such as the Waiheke marina, and individual pairs are often physically removed or blocked out of nest sites under houses, whose owners object to their presence. They’re also killed by cars where coastal roads run between breeding areas and the sea. However, kororā respond positively to predator control and the provision of safe nest boxes.
Oil spills can be lethal for penguins and kororā were significantly affected during the oil spill from the grounding of the Rena off Tauranga, which killed 2,000 seabirds (including little penguins) directly, and an estimated 20,000 through wider ecosystem impacts. Kororā also swallow plastic, mistaking it for prey items. The worst result of ingesting plastic is that it can occupy space in the stomach leading to starvation. Other larger plastic items, such as bottle packaging rings, can become entangled around penguins’ necks.
With kororā effectively being our town’s mascot, I’m sure we all want them to thrive. You can do your bit by controlling your pets and also reporting any sightings to Project Island Song, saying where and when you saw them, what they were doing and including photos, should you have any, to info@projectislandsong.co.nz.
Kororā | Little Blue Penguin | Eudyptula minor