These are Adelies.
And this is the longest penguin migration on Earth.
Adelies don't lay their eggs on ice, so these males have traveled 13000 kilometers to reach an area of Antarctica with bare rock.
99% of them return to the same nests each year.
But after a harsh winter, the entire breeding ground is in need of renovation.
And time is of the essence.
The males have just days before their partners return.
No other penguin in the family puts as much effort into building its nest.
And this conscientious male takes his time selecting the perfect pebbles.
Finding stones that are just right isn't easy.
So some sneaky individuals have found a shortcut.
This poor male seems unaware that his hard work is being undermined.
The thief's nest, however, is coming along very nicely.
He clearly knows to keep a sharp lookout for raiders.
With a little encouragement from dad, he takes his first steps onto the snow.
His feet are perfectly adapted to the terrain, with special fats to keep them from freezing and strong claws to grip the ice.
Dad keeps a close eye, But these first solo explorations are so important for this chick's eventual independence.
Being able to make new friends will be crucial to a successful life in the colony.
But it can be dangerous to stray too far from Dad.
So strong is the parental urge to raise a chick that these adults who have lost their chicks in the bitter storms try to kidnap others.
Desperation can turn to violence.
This chick has had a lucky escape.
The volatile Antarctic weather can change in an instant.
Despite its cold weather adaptations, this chick isn't quite ready for complete independence.
Without its insulating adult feathers and the warmth of its parents, it will perish.
The chick's call is as unique as a fingerprint.
Even from a distance, through howling winds, Dad recognizes it.
That's enough excitement for one day.
This is just one of the many forest clearings where the penguins come to nest.
With no native land predators.
New Zealand has always offered these flightless seabirds a sanctuary, a safe haven for rearing their young.
But there is one big disadvantage to forest living.
Mud.
Thousands of tiny webbed feet turn the damp ground into a veritable quagmire.
This doesn't just result in a grubby appearance.
It could threaten their lives.
A penguin's feathers are crucial for waterproofing and insulation out at sea.
If they're clogged with mud, penguins can't regulate their body temperature and could die from the cold.
But the snares have found a solution.
It's time for a trip to the penguin baths.
After a thorough rinse, the penguins spread a very special wax through their feathers.
Produced in a gland at the base of the tail, it creates a waterproof barrier that insulates and streamlines.
The wax is also antimicrobial, deterring unwanted germs.
For some penguins, this process can take up to three hours a day.
But it's a price worth paying for their forest sanctuary.
A dense coat of feathers that keeps her warm in cold seas now stifles her.
On these exposed rocks, she must shade her eggs instead of keeping them warm.
Everything here seems the wrong way around.
For some, the soaring temperature is too much.
A neighbor deserts his nest.
His egg will not survive.
He's not the only one to give up.
Some years, not a single chick is reared.
Penguins are adapted to withstand temperatures of 40 degrees below zero.
Not 40 degrees above.
Now, at the hottest part of the day, the very worst time, her chicks are hatching.
Just when they need her most, she's reaching the limit of her endurance.
After 10 days of intensive fishing, the chick's father comes back to take his turn at the nest.
But will he be too late? he greets his young for the very first time.
On Paulet Island, the snow has turned to sleet.
It's now muddy, cold and wet.
A potentially lethal cocktail for the young Adélie penguins.
The chicks hatch in late December.
In the first few weeks, they're extremely vulnerable.
The fluffy down coats keep them warm against the fierce winds and snowstorms, but they give no real protection against the wet.
In an average year, a third of all the chicks die.
I'm visiting the colony in late January.
The chicks have grown quickly and at this stage the chance of survival is much higher.
Both parents are able to leave their young to hunt for food.
Just a few adults are left to keep watch over huge chick creches.
Now, when the hustle and bustle of a penguin colony is at full tilt, like it is now, both parent birds spend as much time at sea fishing as possible.
But imagine what it's like being an adult penguin returning to your colony and being confronted with a scene like this.
How on earth do they actually recognise their own chicks?
Now I can tell you something.
It's not a visual cue because, let's face it, every chick here looks pretty much the same, and they're changing their appearance on a daily basis as they molt from that fluffy chick down to their first diving plumage.
The secret to how this colony works is all down to sound.
Now in my headphones I am listening to the call of a single chick, but this sounds very much like the noise that chick's making, like that chick's making and like that one, in fact, all of these.
Now to a penguin.
That wouldn't be a problem because, in the same way you may recognise a member of your own family calling out to you in a crowded room, penguins can do the same.
Every single one of these noises is subtly different to the other one, which is probably just as well, because if I take my headphones off, this is the reality that hits my ears.
When the parents return with food, the youngsters have to do much more than sing for their supper.
They often take part in what's called food running.
Successful Adelies bring up two chicks.
The adults make these young chase after them.
Now, scientists aren't sure why all this energy is wasted.
It may be to reaffirm the bond between parent and chick, but in lean years it often sorts out the strong from the weak.
Only when the parent is convinced it's feeding the right chick will it regurgitate supper.
It may look disgusting, but a recent study has found that when penguins go fishing, they switch off their digestion, leaving the fish for the young undigested in the stomach.
So this chick is actually getting a fresh seafood dinner.
Well, I have decided that the only way of understanding why penguins are such beautiful birds is to actually get into that environment for which they are superbly designed.
But I must admit I'm feeling rather envious of them already, just look at that.
That is a fully prepared diving machine.
I feel like the most cumbersome thing on the planet in comparison, and I've still got loads of kit to go.
By the way that water is expected to be about minus two degrees.
So I'm not going to be in there very long at all.
But let's have a go, see if we can see any penguins.
OK, race you.
Even with Navy backup, planning a difficult dive like this takes days.
Penguins, on the other hand, take a few seconds deciding on the depth and taking on exactly the right amount of oxygen.
I won't be able to dive to more than 30 feet, while our dailies have been recorded reaching depths of 574 feet.
And forget the idea of diving for 18 hours.
In this cold, I'll be lucky to stay underwater for 18 minutes.
Wow, this is fantastic, but I am envying those penguins.
For a start, it's really cold.
Not only do I lack the really effective insulation of the penguin, but in comparison to their manoeuvrability I'm actually rather sluggish.
Still haven't seen a penguin yet.
I'm going to check out the iceberg to see where they've got to.
And I don't have to wait for long.
They've shot into the water like black and white torpedoes.
These penguins don't hang around for me.
Not surprising, really.
Underwater, I look like one of their top predators, the leopard seal.
Scientists suspect their sense of smell might guide them to areas that are rich in prey.
They fluff an insulating layer of air into their feathers before diving down to the chilly depths.
Our parents will make up to 400 dives on a typical trip.
The longer they search, the more energy they burn.
And with hungry chicks waiting to be fed, the clock is ticking.
So what our cameras film next is a real surprise.
Inspection!
Can you see that?
Just had a look at it, said no, not for me.
After hours at sea, Our hungry penguins are ignoring perfectly edible prey.
Whoa, straight past the shrimps.
Shrimps, squid and lobster krill are all passed up.
The penguins are taking a massive gamble.
Their chicks will starve if they leave them for too long without a meal.
The penguin parents keep searching until they finally find what they're after.
Oh, look at that!
Anchovies.
These oil-rich fish are penguin superfood.
Our cameras first show the penguins dropping beneath the fish.
The air in their feathers makes them so buoyant that they shoot up into the shoal.
Anchovies are the highest quality food these parents can feed their chicks.
And that can mean the difference between life and death.
All the penguin activity attracts other seabirds.
Everyone is sweltering.
Even the neighboring elephant seals are throwing wet sand over themselves to cool off.
The adult penguins can head off to fish in the refreshing South Atlantic.
But the chicks still have their downy winter overcoat.
They can lose some heat through their enormous feet, but not enough.
These chicks take more than a year to fledge, and it'll be another two months before they can swim properly.
So they take a tentative dip in a chilly, glassier stream. on your feet.
So they find an alternative.
A muddy pool, just cool enough to be refreshing.
Now that was fun.
Southeast of Hawaii, straddling the equator, lie the Galapagos Islands.
As on Hawaii, some of the volcanoes here are still very active.
The coastline of Isabela, the largest island, is covered in volcanic rock.
Here, a very different kind of animal can be found in the rocky tubes.
The chicks of Galapagos penguins.
Without the lava tubes, they wouldn't survive.
Cool and sheltered.
The tubes are the perfect nursery, protecting the chicks from the unforgiving temperatures outside.
Unforgiving if you're a penguin, that is.
Adult Galapagos penguins only cope by doing something the chicks can't yet do.
They take a dip.
The adults plunge into cool waters that have traveled all the way from the Antarctic.
Who says penguins can't fly?
There's lots of food here, as schools of fish are drawn to the shelter of these rocky volcanic shores.
But while the parents are out fishing, their chicks are home alone.
Back in the lava tube, there's something creeping around.
A Sally Lightfoot crab has peng-weng on its mind.
It's dark, so the crab can't be sure exactly what it's up against.
This time it's taken on more than it can handle.
Had the encounter been just a few days earlier, the outcome might have been very different.
Crabs are major predators of baby penguins.
Even when more sea lions arrive, they can't seem to break down the sardines' coordinated defenses.
With a shoal this big, the sea lions need to isolate a smaller, more manageable group of fish.
But with so few predators, the fish still have the advantage.
All the sea lions can do is keep the sardines at the surface and wait for others to join them.
Tuna.
Their arrival changes everything.
Tuna attack from below, cutting off the sardines' escape route down to deeper water.
Next to appear, shearwaters.
Excellent flyers, but also surprisingly agile underwater.
With so many predators attacking from all sides, the advantage starts to shift away from the sardines.
As the fish pack ever tighter, their shoaling strategy now makes it easier for the hunters.
Copper sharks.
They've scented blood in the water.
Surprisingly, perhaps, the predators never attack one another.
They work together to corral the ball of fish, taking turns to grab a mouthful.
Common dolphins.
As the shoal gets ever smaller, each sardine scrambles desperately to hide in the middle.
But now there's no escape.
A brooder's wail finishes off the feast.
Tons of sardines devoured in less than an hour.
