Cosmos
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By Cosmos
An immersive Antarctic adventure with Scenic Eclipse
By Ian Connellan
There are a few birdlife guarantees in life. Seagulls at Bondi Beach. Pigeons in New York (or London, or Melbourne, or Venice). Blue-footed boobies in the Galápagos Islands. And, should you happen to visit Antarctica, penguins.
It’s a little hard to imagine until you experience it, but penguins really are just about everywhere you look if you’re cruising in the Antarctic Peninsula. And in no small part because it takes the least time to reach by sea – a couple of days from the port of Ushuaia, in southern Argentina – the peninsula is the part of the continent experienced by the vast majority of Antarctic visitors.
As of last December, those visitors include the authors of this story, who travelled to the deep south as guests of Australian ultra-luxury cruise company Scenic, aboard the glamorous and extremely comfortable Scenic Eclipse. Everything inside the vessel was luxurious – but that’s another story.
The reason people travel to the Far South is to experience what’s outside: the frozen continent and its wildlife, particularly penguins. Our guides were Scenic Eclipse’s 20-member Discovery Team, especially Argentine-born ornithologist Agus Biasoti, and scientific guests on the voyage Melissa Rider and Steve Forrest. Steve and Melissa, who have nearly 60 Antarctic seasons between them, were there to conduct a penguin census for Oceanites, a US-based not-for-profit focused on Antarctic wildlife conservation.
Facts about Antarctica’s penguins
Let’s get our facts straight from the go-get. It might surprise you to know that only four (of the world’s 18) species of penguin live in Antarctica. Penguins are the poster fauna of the Southern Hemisphere, even though Galápagos penguins scoot across the equator now and then. Species are scattered across the south, but only a few inhabit the Antarctic continent. The emperor and Adélie penguins are endemic to its waters, while the Adélie’s close relatives the chinstrap and gentoo penguins are found at many other southern hemisphere islands as well as Antarctica.
Agus whet our appetites for penguin knowledge early in the voyage during an ‘enrichment lecture’ in Scenic Eclipse’s state-of-the-art theatre. He explained that penguins get their collective name from the great auk (Pinguinus impennis), which inhabited the North Atlantic until driven to extinction by humans in the mid-19th century. Although barely related to penguins, the flightless auk resembled them both in appearance and behaviour (a classic case of convergent evolution), and the late-16th century European explorers that first encountered penguins named them for the auk.
“So, if you have to survive such a difficult environment as this with cold weather and wind and snow, of course you need good thermal regulation,” Agus says. “If you’re naked in Antarctica you’re not going to survive for long. But [penguins] survive here in the water most of the year.”
How penguins survive in these harsh conditions
Penguins have three layers of thermal protection. First, their uropygial layer of feathers forms a waxy, waterproof exterior, which must be constantly maintained by preening with oily secretions from the uropygial gland near the tail.
Beneath the waterproof feathers is a layer of various types of downy feathers that traps air near the skin. And finally skin and body fat – blubber – form the ultimate seagoing insulating layer when at last water pressure pushes out the trapped air. The ‘true’ Antarctic penguins – the emperors and Adélies – have skin about 4mm thick and blubber up to 20mm thick.
After Agus’s lecture, we couldn’t wait to meet them! And meet them we did: at least, we met Adélies (Pygoscelis adeliae), on our first peninsula Zodiac excursion, at the Madder Cliffs on the western end of Joinville Island, which is nearly the northernmost tip of the Antarctic Peninsula.
Adélies penguins and other southern birds
The Adélies and other bird species – including Antarctic shags and various predators including skuas and giant petrels were massed on shore around the bay – but it was their presence in the water that was most alluring. On land, they move comically (a trait shared with other penguins) and slowly. But they’re natural swimmers, and ‘fly’ through the water at about 8 km/h, and nearly double that when they’re pursuing prey – mostly krill – or dodging predators such as leopard seals or killer whales. When they’re chasing food, Adélies regularly dive to about 150m, and they’ve been known to go to 180m. They can hold their breath for up to six minutes.
You wouldn’t describe Adélies as small birds. Adults are around 70cm tall and weigh in the 4–8kg range (think about it next time you buy a decent-sized chicken to roast). They’ve certainly got a bit of small-bird syndrome with a matching temper, and have been recorded muscling up to large predators like giant petrels. Perhaps they’re eternal teenagers? That’s certainly what they look like when they’re lined up at the water’s edge, waiting for someone to jump in first (and thus be the crash-test potential prey for any passing marine predators).
Their delightfully Francophile name comes courtesy of French explorer Jules Dumont d’Urville, who named them after his wife Adéle after first seeing them in 1840.
What do you call a group of penguins?
We saw Adélies in large groups – we decided the appropriate collective noun for all penguin species was a ‘squabble’ – and had no hope of telling males and females apart. They’re about the same size and look much alike: a classic, out-of-a-picture-book tuxedo-clad penguin. Their white-ringed eyes stand out a little googly-eyed from black heads, and their white chests and bellies provide excellent camouflage against marine predators looking up from below to the water’s surface.
Incredibly, these dapper little seabirds are left in creches in their breeding colony when only 3 weeks old. Both parents go to sea to collect food for their chick; they stay out for up to three days and might go as far as 120km offshore. Racing to beat the fast-closing cold, chicks go to sea when they’re only 7–9 weeks old. Most won’t come back again, to the same colony, until they’re old enough to breed at 3–5 years old.
Chinstrap penguins at Palaver Point
A few days later and further south, at Palaver Point on Two Hummock Island, we have the privilege of kayaking among chinstrap penguins – paddling close enough to witness them ‘flying’ through the icy sea as they forage. A place name including the word Palaver gives away an important fact about penguins: these are not silent animals. A penguin rookery is as noisy as an unsupervised primary-school class.
That afternoon at Hydrurga Rocks (named for the leopard seal – Hydrurga leptonyx), we met the chinstraps afoot. The rookery was a lively place. Chinstraps loped to and from the water along ‘penguin highways’ in their odd, swaying gait; mating pairs called to each upon reuniting – it was quite a din.
Chinstrap penguins (Pygoscelis antarctica) get their name for the narrow band of black feathers that extends from ear to ear below their chin and the cheeks – just like a helmet chinstrap. They’re a similar size to Adélies – and like Adélies, males and females look similar. They also have the same black-and-white, dressed-for-dinner look that’s effective camo against marine predators.
We got great demonstrations of one of chinstraps’ signature moves: they like to toboggan on land – propelling themselves forward using their feet and flippers while lying on their stomachs. They’re also renowned for jumping over large distances and we spent several happy minutes watching a group returning from sea jumping their way back to their nests.
Chinstraps share with Adélies a trait biologists call “site fidelity”: they invariably return to the nesting site where they were raised when it comes time to breed (at 3 years of age); it’s believed generations over thousands of years may have followed this habit. They build nests out of stones, and pebble stealing – taking a stone from a neighbour’s nest and adding it to their own – is a common sport, and the source of much rookery unrest. They generally raise two chicks each summer – other penguin species feed the stronger of their chicks preferentially – after a month-long incubation period that’s shared between males and females.
Their breeding colonies are mainly found on the Antarctic Peninsula and on South Atlantic islands, and far enough south that persistent sea ice can upset breeding some years. Chinstraps leave their breeding colonies during March–May to move north of the pack ice for the winter, and generally return to their colonies in October–November.
The genuinely weird trait of chinstrap penguins
A recent research paper in Science has discovered that chinstraps have a genuinely weird trait: they accumulate about 11 hours of sleep daily by taking more than 10,000 four-second microsleeps. The nesting adults certainly looked like they were resting up after feeding at sea – where they hunt for fish and krill – but we couldn’t pick a micro- from a macrosleep.
On Hydrurga a snowstorm gradually increased in tempo, and the sight of chinstrap penguins going about their business against a backdrop of glaciated mountains, icy oceans and snowfall is one of our most enduring memories of visiting Antarctica. Life in the freezer indeed.
Gentoo penguin rookery, a sight
Christmas Eve was the day we got to walk on the Antarctic continent (rather than an island near it). We went ashore at Neko Harbour, on the Graham Land coast, site of a large gentoo penguin rookery.
The gentoo (Pygoscelis papua) is the second largest Antarctic penguin – after the emperor – and the third largest overall (the king penguin, which breeds on subantarctic islands, is also larger). Gentoos grow up to 90cm tall and can weigh more than 8kg; their penguin superpower is swimming – they’re the fastest underwater swimmer among penguins, and can reach speeds over 30 km/h. They’re also more opportunistic than Adélies and chinstraps when it comes to diet – yes, krill and fish, but many other marine creatures as well – which gives a clue to how they’re going in comparison to the other Antarctic penguins.
“We’re seeing that gentoos are actually expanding their population range in the western Antarctic peninsula,” Steve Forrest told the audience during a later enrichment lecture. “The Adélies and chinstraps are both in decline. Gentoos are opportunistically colonising, and because of their site fidelity, Adelies and chinstraps are just trying to stick it out in those same [nesting] spots … and it’s just not working out for them in this changing environment.”
They also have another critical behavioural adaptation. “They’re more likely to re-lay,” said Steve. “So when we get those big random dumps of snow during the breeding season that really affects these other species, and nests are lost due to the eggs getting wet, gentoos can re-lay … their eggs. The other two species are very unlikely to do that.”
With just the hint of a smile, he added: “We call that gentoofication.”
Like their Adélie cousins, gentoo behaviour often points them toward the teenager class. At Neko they have a beach to enter the water from, rather than launching off an ice shelf, and they’re particularly teen-like at the water’s edge. Many stand knee-deep in the water and appear to be contemplating the temperature. Or perhaps they’re thinking about food – which, like so many things in Antarctica, isn’t as straightforward as it appears.
As with other penguins and marine bird species, the gentoos’ diet is high in salt – not surprising given that they feed on prey that’s about as salty as seawater. High salt concentrations in the body can cause problems, especially for chicks, so gentoos and other seabird species have a salt gland in their head that converts concentrated sodium in the body into a highly saline solution. This liquid concentrate drips out from the tip of the beak – a nifty adaptation that allows gentoos and other penguins to survive without fresh water.
Searching for an Emperor penguin colony
It was Boxing Day, and our last full day in Antarctic waters after an incredible 12 days at sea on board the Scenic Eclipse. Around the middle of the day, Scenic Eclipse pushed into sea ice in Charlotte Bay, more or less to see what we could find. Here and there were penguins resting on the ice, and – much more widely scattered – crabeater seals. In the distance off Scenic Eclipse’s port side, humpback whales surfaced in leads – cracks – in the ice; various seabirds, a great many of them kelp gulls, were on the wing or on the ice.
When we’ve been stationary for perhaps an hour the voice of lead expert Discovery Leader, Helena Schofield came on the PA: a sole emperor penguin had been seen off the port side.
The bird enthusiasts on board grabbed their cameras and complimentary binoculars and raced outside – if they weren’t, like us, already there. There was a moment earlier in the voyage when the possibility of visiting an emperor colony had come up – and almost as quickly evaporated. An individual animal wasn’t quite the same as visiting an emperor colony, but it was good enough to get a tick on a bird list.
In awe of the Emperor penguin
Emperor penguins (Aptenodytes forsteri) rightly inspire a kind of awe. They’re the biggest penguin species at up to (sometimes exceeding) 1m tall and weighing 40kg or more. King penguins stretch towards emperors on one measure (they’re 80–90cm tall) but at 10–15kg on average they’re well behind on body mass. But it isn’t just about size.
Alone among Antarctic animals – all animals, not just penguins – emperors breed during the bleak winter months. They’re uniquely adapted to survive in places where temperatures can drop to -50°C and winds can reach 200 km/h. Unlike most penguins they’re social creatures, and they huddle together to keep warm – a key survival behaviour. Because they huddle, they don’t spend energy defending territory. They’re the only penguin species that’s not territorial.
On the physiological side, they have large reserves of energy-giving body fat (hence their hefty weight) and their activity is limited during winter. Relative to their size, their bills and flippers are small, to conserve heat, and their several layers of scale-like feathers aren’t ruffled until winds blow past 110 km/h. They have special chambers in their noses that save much of the heat that’s normally lost exhaling breath, special fats in their feet that stop them from freezing, and unusually strong, ice-gripping claws.
Our emperor visitor seemed to be feeding. It periodically appeared in an ice-free pool, then disappeared underwater for several minutes, before popping up again. Just the distant sight of it caused outbreaks of smiles.
Emperors incubate their eggs through the depths of the Antarctic winter. Females lay a single egg in May or June, then the males take over and incubate the egg in a special brood pouch – carefully keeping it off the ice – for the next nine weeks, while their mates are feeding at sea. The males don’t eat for even longer than that; it could be as long as four months – from when they arrive at the colony to breed, through incubation, egg hatching and the mother’s return. Close to 50% of their body weight falls away through this period. It’s the body fat reserves that they built up during their summer feasting that keep them alive.
And what a feast! Through summer emperors gorge on krill, Antarctic silverfish and other fish species, and some squid species. An adult emperor consumes about 2–3 kg per day on average, and up to twice that on a bumper day. While they’re feeding they demonstrate why they’re the penguin-class diving champions. They generally hunt food at 150–200m depth, but the deepest emperor dive recorded is 565m. They usually stay submerged for 3–6 minutes but can go much longer – the longest recorded dive is 22 minutes.
Emperors under threat
Given all that’s amazing about emperors, predictably there’s some bad news: these giants of the penguin world are the species perhaps most threatened by climate change. The IUCN moved emperors from their list of least concern to the near threatened list 2012; the main risk they face is declining food availability due to the effects of climate change. But overall numbers are for the moment only dropping slightly, and for reasons not entirely clear, as a 2024 study in Proceedings of the Royal Society B reported.
Certainly, isolated climate events can have a big impact. In spring 2022, record low levels of sea ice in the western Antarctic Peninsula led to a “catastrophic breeding failure” of the region’s emperor penguins, according to a study published in 2023 in the Nature journal Communications Earth & Environment.
Climate change risk for Antarctica and its penguins
Where Antarctica and its penguins are concerned, climate change casts a long, dark shadow.
“This is what we do know for sure,” Steve Forrest told us. “Temperatures in the peninsula have been going up dramatically over the last several decades – year-round a 3°C change.
“This is a dramatic, impactful, change [and in the peninsula] we’ve been seeing it in terms of the reduction in glacial mass, reduction of sea ice annually, and that affects kind of everything that happens here.”
For now the effects aren’t accelerating any penguin species to oblivion, but as Oceanites’ long-term census work indicates, things are changing.
“Penguins are long-lived species, so they can give us a good idea of what’s happening in a climate from year to year and decade to decade,” said Steve. “We study penguins because they’re central to the food web. Penguins’ health tells us something about their predators, the whales and seals, and of course their breeding success tells us about the things that they prey upon, so the fish, the squids, and most importantly, of course, the thing they eat the most – the krill.”
From the deck of a cruise vessel that’s close to land in the Antarctic Peninsula, you don’t need to be reminded of penguins’ centrality here. The view is dominated by cold, iceberg-speckled water and land with towering mountains buried beneath untold tonnes of ice. Cast your eyes around and you might see whales, or seals, or a bird in flight. But all this will be accompanied by gentle pops and splashes as the ubiquitous penguins go about their day, swooping and gliding above and below the water’s surface.
Inspired by this piece? Now is the time to secure your voyage to Antarctica on board Scenic Eclipse in 2025 or 2026. Visit scenic.com.au, call 138 128 or contact your local travel advisor.