This Is How It Ends: How we're driving our distinctive native penguins towards extinction

Tuesday, 19 October 2021

Commercial fishing, introduced predators and climate change are putting penguins and other unique seabirds on the edge of survival. (File video)

New Zealand has already forced one penguin species into extinction – will the rockhopper, hoiho or little blue follow? Andrea Vance and Iain McGregor report for Stuff’s This is How it Ends series.

The windswept mountains and jagged coastlines of Campbell Island/Motu Ihupuku sit profoundly alone in the crashing waves of the Southern Ocean.

In the rocky crevices of this remote place, eastern rockhopper penguins make their home.

But although they are thousands of kilometres away from humans, our activities are still interfering with their delicate web of life, causing the population of this plucky seabird to crash.

As the world faces a dual climate and biodiversity crisis, seabirds are among the greatest casualties.

A rockhopper penguin leaps between boulders on Auckland Island.

New Zealand is a magnet for seabirds: of the world’s 346 seabird species, 145 use our waters and 95 breed here. That makes the loss more pronounced, with 90 per cent of seabird species threatened or at risk of extinction, more than any other country.

Their greatest enemy is us, the ever-growing human population. The pressure we put on ecosystems – through introduced invasive species, changes in land and sea use, direct exploitation and harvesting, pollution and climate change – has triggered a wave of extinctions, with more predicted to be lost over the next century.

“We are at crisis point,” Livia Esterhazy, chief executive of WWF-New Zealand, warns. “The way we feed and fuel our 21st-century lifestyle is unsustainable, we have fundamentally changed the planet. And it's completely out of balance.

“Biodiversity loss is incredibly serious. Because it basically underpins every life form on this planet. It produces our food, it gives us our air and our water and our shelter.

“When nature collapses our air will be unbreathable, we will not be able to drink water, we will find it incredibly hard to produce food. And then chaos will reign. We cannot have nature collapse on us because that threatens our very own existence.

“We are the most dangerous creature on this planet.”

There are three subspecies of rockhopper across the world, all of which saw large-scale declines in the 20th century from more than 5.5 million breeding pairs to less than 1.5 million.

“Our” eastern variety is among the world’s smallest penguins – weighing between 2 and 4kg. And they are the most charismatic of New Zealand endemic penguins.

Eastern rockhopper penguins are fiercely territorial.

Short and stocky, they display a yellow crest of feathers on their brow – as extravagant as a drag queen’s eyebrows.

They were named for their adorable bounce: to navigate the rocky terrain they hold their feet together and hop over crevices, and even dive feet first into the waves.

Fifty years ago, the rocky crevices of Campbell Island held some of the largest rockhopper colonies in the world. Now the population is dwindling.

But although their locomotion is endearing, rockhoppers are fiercely territorial and noisy scrappers.

They once thrived on Campbell Island’s coastal slopes, but are now fighting for survival. Since the 1940s scientists have recorded a dramatic fall (94 per cent) in numbers – down from 800,000 pairs counted in 1942 on the island to around 51,500 today.

The number of nests of eastern rockhopper penguins on the Antipodes Islands has also dropped from 1242 in 1995 to 885 in 2011, a 29 per cent decrease.

Rockhopper are distinctive for a yellow crest of feathers on their brow.

“The prognosis for rockhopper penguins, at least in New Zealand, is not fantastic,” says David Thompson, seabird ecologist at the National Institute of Water and Atmospheric Research (Niwa). He has made frequent trips to study New Zealand’s most far-flung islands.

“I remember one particular visit [to Campbell], where we were expecting to find a bunch breeding where they were breeding the previous year. And we found not a single one.

A hoiho/yellow-eyed penguins calls for its mate on subantarctic Enderby Island.

“So, a little sub-colony of penguins disappeared in the space of 12 months. These birds are in trouble.”

A joint Niwa-Massey University study in 2012 attributed the decline to climate change.

“It has something to do with what’s going on in the marine environment. It’s an oceanographic shift … which is affecting the food supply of these animals,” Thompson says.

“Another species of penguin in that part of the world, the erect-crested penguin, is also in decline. So, the two southern subantarctic species of crested penguin in New Zealand are both showing a similar pattern of decline.”

Penguins are at the mercy of predators, such as skua.

New Zealand is a stronghold for penguins, with more species on our shores than anywhere else in the world.

Thirteen of the world’s 18 penguin species have been recorded here, and nine breed in the region, including three (Fiordland crested penguin/tawaki, little penguin/kororā and yellow-eyed penguin/hoiho) that nest on the mainland.

Sadly, it’s a pattern repeated across the globe: 55 per cent are at risk, with 10 species on the IUCN Red List, making penguins the second-most threatened bird group after the albatross.

Hohio/yellow-eyed penguins make their way onto land after spending the day foraging at sea off Enderby Island.

“It's a mixed bag,” Graeme Taylor, principal science adviser for the Department of Conservation, says. “We've got some species doing quite well. The Snares crested penguin seems to have been stable for quite a few decades.

“By contrast, we've got the hoiho, the yellow-eyed penguin, which is really in serious decline on the mainland.”

Tall, with a distinctive pale stripe of yellow feathers around the eyes and a shrill call, the hoiho (noise shouter) was already one of the world’s rarest penguins.

After recovering from a massive population drop in the 1990s, hoiho are once again on the slide with only an estimated 5000 left.

After recovering from a massive population drop in the 1990s, they are once again on the slide with only an estimated 5000 left. Warming oceans in the last half-century, and interaction with fisheries, left them with a conservation status of “threatened – nationally endangered”. The IUCN recognises them as endangered.

Snares crested penguins are unusual: their population is apparently stable, while six of the seven other crested penguin species have declined over the last century.

Taylor believes they may be struggling to find food. “Most of the researchers working on them are not that confident. Sadly, Whenua Hou [Codfish] Island, which is predator-free, has had a massive decline in its population.

“So, it's nothing land-based that seems to be affecting them. There's something going on in the ocean.”

Snares crested penguins' breeding islands are all free of introduced predators.

Hoiho fish from the seabed and Taylor says bottom trawling, dragging heavy weighted nets across the sea floor, could be to blame. “There may be a long, gradual loss of high-quality habitat, and they're just not going to be able to bounce back.”

Being flightless, penguins can only swim to forage. “There’s only so far they can swim in a day to get food to come back to feed their chick. So they’re dependent on quite a small area. If there’s a very local change in that food stock, it can really affect their ability to produce chicks.”

Their natural predators – sharks and seals – find them at sea. But now they face threats on the mainland.

There are 3200 to 3600 yellow-eyed penguins left in the wild, down from nearly 7000 in two decades.

Human noise and presence stresses them out, delaying adults’ return to starving chicks.

Nesting and moulting birds are vulnerable to introduced pests such as stoats and ferrets, which will pull chicks from nests, as well as dogs and cats. “Just one short bite, they puncture into the body of the bird, and it’s going to die, basically. There's been whole colonies up in northern New Zealand wiped out from a single dog attack,” Taylor says.

There are 18 species of penguin globally, and 13 of these have been recorded in New Zealand territory.

Hoiho are the local species most affected by habitat loss, as their shrub and forest nesting sites are replaced with pasture and coastal development.

Professor Phil Seddon, of Otago University’s Department of Zoology, points to disease.

“The chicks are getting diphtheria-like lesions in their mouth, that’s knocking them off. We’ve had a couple of incidents, over the last decade or so, where apparently healthy yellow-eyed penguins have walked out of the sea, taken two steps up a beach and dropped dead. And we don’t know why.”

Rafts of penguins move as one: porpoising across the water in a series of consecutive leaps.

Unexplained mass mortality events of adults are especially worrying, he says. “They are the critical ones, the ones that are producing the next generations, in reasonably limited areas.”

Changes to habitat, coupled with the effects of climate change, reduce the birds’ ability to cope with disease.

“We talk about resilience, the ability to bounce back from, from disturbance.

Antipodes Island is a breeding ground for large colonies of erect-crested and eastern rockhopper penguins.

“So, if you had a big healthy population you have diversity: diversity of behaviours, diversity of genetics – biodiversity.

“If something changes, a proportion can probably cope with it, can do well. But if you shrink that population down, you lose resilience, that ability to react to change.”

New Zealand has already lost one penguin species: the waitaha penguin, which seems to have died out in the 15th century.

Pico arrived at the International Antarctic Centre in Christchurch with a serious eye injury.

Otago University scientists discovered its existence in 2008, initially believing they were studying old hoiho bones.

“Taxonomically, [the yellow-eyed] is the only member of its genus, that megadyptes. There aren't any other like it,” Seddon says.

Staff at the International Antarctic Centre care for injured penguins unable to survive in the wild

“But it didn't use to be here. It’s only been on the mainland for about 500 years.

“[There was] another megadyptes, but it occupied the mainland. And the two didn’t really mix.

Keeper Alyson Findlay reads The Lonely Penguin storybook to Pico.

“But, for probably human disturbance reasons, the population of that original species disappeared when the first people were exploring the coast along here. It’s what we call a cryptic extinction.

“It was replaced by yellow-eyed penguins that managed to colonise the mainland.”

Penguins are among the 4000 native species under threat of extinction in Aotearoa.

The timid tawaki are found at Milford Sound, Jackson Bay and close to Lake Moeraki, near Haast.

Human intrusion and predators have seen their numbers fall since the 1950s, down to an estimated 2500 to 3000 breeding pairs.

The same risks face kororā (known as little blue penguins). Once common, the world’s tiniest penguin has now been driven out of almost everywhere that isn’t protected from predators.

Little blue penguins are the world's smallest penguins.

Coastal development, such as the construction of a new Waiheke Island marina, disturbs their traditional nesting sites. They are also killed on roads, by boat strike or drowned in set nets.

In January, a half-blind and underweight little blue arrived at Christchurch’s International Antarctic Centre, after washing up on a beach near Kaituna, Coromandel.

Kororā are the smallest penguin in the world.

“They have had a pretty massive injury of some kind, which has affected their sight,” penguin keeper Alyson Findlay explains.

“They have one completely blind eye and potentially partial vision in the other. So that makes them unfit for the wild.

Pico had to be euthanised after repeated eye infections.

“Penguins have three eyelids. The third eyelid is clear, and they can close it just before they dive into the water, it keeps their eyes free of debris. So not having all of those eyelids working can be a bit of a hazard when they're out fishing or trying to get away from predators and things.”

The penguin rescue centre is a last resort – and the little blue was lucky to secure a spot. “They were flown down: the only time that penguin will ever fly,” she says.

Staff named the bird Pico – and because penguins have no external genitalia, it took a DNA test to determine she was female.

Pico quarantined for four weeks, to avoid passing on disease to the centre’s 17 other little blue and white-flippered penguins, which are endemic to Canterbury.

The huddle have different injuries, from damaged beaks and fractured flippers to paralysed tongues and broken ankles.

Because the penguins are hand-fed sprats, they must be taught to trust their human keepers.

“Most of them think of us as a big scary predator,” Findlay said, as she nursed the bird through quarantine. “So we read them stories, sing songs, sit with them over our lunch breaks, get them to trust us enough to take fish from us.”

The penguins only weigh about a kilo, but they are feisty, with beaks as sharp as a knife that grab and then twist.

In the water, their bluish-grey feathers blend into the ocean camouflaging them from airborne predators, like petrels. Their white bellies merge into skies above, shielding them from sharks looming underneath.

In short bursts of speed, up to 20kmh, they can evade predators but usually cruise along at a more comfortable 4-6kmh. With powerful flippers, they have the ability to dive down to depths of about 70 metres, holding their breath for about four minutes.

The penguins spend about 16 hours a day at sea, leaving at 4am and travelling anywhere between 15 and 90km.

At sunset, they begin to form groups – known as rafts – for a safe return to shore. On land, their collective noun is a waddle.

When they arrive on land, they are fragile. Breeding season begins in spring, and they return to the coasts where they were born – sometimes even the same nest where they hatched.

The parents take turns in incubating the chicks for 40 days, and then feeding them for a further eight weeks. When their bellies are full, their flippers begin to shake – an endearing signal to kick-start their metabolism.

“They have quite a few land predators. Our furry friends, feral cats and dogs off of leads, as well as stoats, possums, ferrets, rats, and even hedgehogs who have been known to eat penguin eggs,” Findlay says.

“It can be a pretty tough life for a penguin out in the wild. They also have diseases like avian pox and malaria.

“And there's a lot of human activity that can be a threat to penguins as well. Penguins can get caught in fishing net lines. Sometimes commercial fishing can take too much fish out of the water and then there isn't enough to go around.

“The boats can give off oils that can affect their feathers, and pollution in the water, as well as on our beaches, can be harmful too.

“Because of all of these things, the average age for a little [blue] penguin out in the wild is only about six or seven years old. They have one of the shortest lifespans of all the penguin species.”

Sadly, Pico’s was cut short. Repeated eye infections plagued her recovery and the centre’s vets chose to euthanise her.

“It was felt that they weren't going to have a very good quality of life while with us,” Findlay says. “So it was quite sad and unfortunately, it is quite common. It’s just the nature of the game.”

Correction: This story has been updated to say the construction of a new Waiheke Island marina disturbs traditional nesting sites, rather than clearing them.