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Antarctica

200 million years ago, our planet looked very different from what it does today. It was entirely covered by sea, which surrounded one single super-continent, we call Pangea. And then Pangea began to break up, life was cast adrift on fragments of land. And these fragments eventually became our seven continents.

We will see how life developed on each continent, giving rise to the extraordinary and wonderful diversity that we see today.

We will venture to the frozen wilderness of Antarctica, where life thrives against the odds. And to the riches of South America, full of the unexpected. From the wilds of Africa, to the vast expanses of North America and the searing heat of Australia. We’ll explore the remote reaches of Asia, home to rarely seen creatures. And to Europe, a world transformed by humanity.

And we’ll discover how this may be the most critical moment for life on earth since the continents formed. We are changing the world so rapidly that wild life is now facing some of its greatest challenges yet. Never has it been a more important time to reveal the precious diversity of life on our seven continents.

This is seven worlds, one planet.

Of all the continents, one was first sighted by humans just 200 years ago. And only now are we beginning to understand what it takes to survive here. It is the most hostile of them all, Antarctica.

98% of mainland Antarctic, an area one and a half times the size of the United Statas is covered in ice, on which virtually nothing can live. So, life is depended on the ocean that surrounds it. But even the ocean freezes, only one mammal can live this far south, the weddell seal. She has to keep her breathing hole open by grinding back the ice with her teeth. Out here on the sea ice, all these seals are far from the predators of the open sea. So this is the safest place for her to give birth. Leaving the warmth of the womb and landing on ice is the sharpest drop in temperature any animal ever faces. But her pup can’t swim for the first 10 days of its life. It’s trapped here, out on the ice. She shields her pup from the wind. Although its spring, temperature can drop to minus 40 degrees Celsius, and blizzards can rage for days. 3 days on, and the storm is still raging. She now faces the hardest of decisions. Does she stay with her pup or shelter in the water? Now her pup’s best chance to survival is for the storm to pass quickly. Some pups didn’t make it. An answer. If this pup now join with its mother in the water, it will be safe from any future storm. It is minus two degree Celsius. But being in the water is warmer than lying on the ice in the howling wind. Its chances of surviving here are now extremely good. Only a few hardy animals can live all year round as far south as this.

Further from the pole, on the fringes of the continent, lies islands that are free of sea ice. Here, there are other challenges. St Andrews bay, on South Georgia, is packed with half a million king penguins. In spring the chicks are left for days, whilst their parents are away collecting food for them. There is a simple arrangement the chicks must stay exactly where their parents left them to be sure of being found again. But this chick has decided to look around. There is a lot to be investigated. But it must not stray too far from its meeting place. This parent has returned with food in its crop, but its chick isn’t where it left it. It’s hard to stay put when there is so much to play with. Elephant seals are here too, very mysterious! Founding it in the crowd of youngsters is not going to easy. They must recognize each other by their calls. But to hear these in such a noisy colony, they must be within 15 metres of each other. Reunited.

St Andrew’s beach is one of the most crowed on the planet, so holding a territory here is constant battle. This bull elephant seal holds the mating rights to 60 females. For two months, he’s guarded this stretch of beach. Unable to feed, he’s losing ten kilos a day and he’s exhausted. But other bulls are lying around waiting their chance. Blubber 15 centimetres thick is protection against the cold, but not from the impact of a four-tonne opponent.  He holds his ground and forces the intruder back out to sea.

Life in the Antarctica is harsh indeed, but all these creatures come here, because the southern ocean is one of the richest on earth. When 30 million years ago, the continent broke away from South America and drifted， south currents began to swirl right around it. They are now the strongest of any currents on the planet. They sweep up nutrients from the depths, and so create one of the richest feeding grounds in all the world’s oceans. And some of the creatures that come here to feast do so in a most sophisticated way.

Humpback whales. It’s summer and they’re come here for a banquet. The cold waters contain great shoals of krill. It is estimated that there are 400 trillion of them. And that their combined weight is greater than that of any other animal species on the planet. To collect them the humpbacks blow curtains of bubbles which the krill won’t cross. The whales then rise spiraling inwards to concentrate the swarm. Summer in Antarctica is a time of plenty when most humpback are able to put on the reserves they need for the whole year.

But wildlife in these waters faces an uncertain future. The southern ocean is warming. 90% of the world’s ice lies in Antarctica, and in some parts the rate at which it’s melting is doubling every decade. Sea levels are rising. But there is a more immediate threat. The warming of the coldest region on earth is having a profound effect on the global weather patterns. And this change in the climate is already being felt right here.

This grey-headed albatross chick is four weeks old. So far, it has been sheltered from the gales by its parents who take turns to collect food for it out at sea. It is the only chick that they will have in two years. A delicate touching of breaks strengthens their bond. But these tender moments cannot last forever. As chick grows so does its appetite, so one parent has to leave find food before the other returns. Parting is a big step and they take time over it. For the first time in its life, this chick is alone.

The Antarctica is the windiest continent, and in recent years climate change has brought storms that more frequent and even more powerful. Winds now regularly reach over a hundred kilometres per hour. But the albatross chicks must try to stay on their nests. Surviving the storm is one thing, but now off the nest in these freezing temperatures, this chick has just hours to live. The brutal conditions have taken their toll.  Some chicks have already succumbed to exposure. The bond is so strong, it can be hard for father to let go. The albatross population here has more than halved in the last fifteen years. These albatross are facing extinction. They simply cannot keep pace with the changes affecting their world. More parents are returning to the colony. Something is not right, the nest should not be empty. The chick is actually right below its parent. But because it’s not on the nest, the parent doesn’t recognize it and doesn’t help it. Strangely perhaps, these albatross do not recognize their chicks by sight, sound or smell. They identify them by finding them on the nest. So these violent storms have created a problem that the albatross are not equipped to solve. If it is to survive, the chick will have to get back on the nest by itself. The chick has made it. The bond is re-established immediately, and its parent once again provides the warmth that the chick so desperately needs. It’s safe for now.

Nowhere in Antarctica is survival easy. Gentoo penguins travel up to 80 kilometres every day to find food. And they are now returning to their chicks. They are the fastest penguin in the sea, and they can swim at 35 kilometres per hour. But other animals can swim faster, orca. This penguin must rely on its agility. With 4 orcas chasing it, the penguin stood little chance. Most Gentoo parents do make back to the colony. Today, it’s been a good hunt for krill, perhaps too good. The chicks grow and it seems that the Mohawk style is back in fashion. It’s just a phase, he will go out of it. He’ll soon lose these remaining down feathers and ready to leave the colony and collect food for himself. But doing so is becoming harder because of climate change.

Glaciers in the region are now carving faster than they have done since records began. And this brash ice now fills the bays. It’s autumn. The chicks have lost their down feathers and they are hungry. They must go to the sea for the first time. But now, there’s a risk of being crushed between blocks of ice. They have to get to the distant icebergs and so reach the open ocean that lies beyond. But that is easier said than done. A leopard seal, their main predator. It’s a giant, 3 meters long. These icy condition help it to hunt. The penguins can neither walk nor swim. They have no way to telling where the seal will strike. These are easy pickings. For some, it’s time to retreat. But now it’s back to square one. There’s no alternative, but to run to the gauntlet once again. This seal seems to be toying with this penguin. The safety is in sight. The ice floe is near the open ocean, but this penguin is exhausted. Perhaps it’s not worth it after all.

Winter is coming. Antarctica now undergoes a major transformation. Every day, a hundred thousand more square kilometres of sea freeze over. By the end of the winter, the continent has doubled in size. This is by far the largest desert in the world. But the frozen surface of the sea hides a great secret.

It may be hostile above the ice, but below it conditions are so stable. The life over millennia has had time to diversify. Creatures here grow to a great size.

These predatory nematine worms are 3 metres long. They are only just beginning to discover the details of the lives of these strange creatures. Nudibranchs are hermaphrodite. Each individual possesses both male and female reproductive organs. So to mate, one nudibranch just needs to find another nudibranch, and anyone will do. But nonetheless this is a challenge when their tiny eyes can barely see. Some do get lucky. They’re fertilising each other, and both can produce young. When it’s hard to find partner, it pays not to have to worry about your gender.

Sea anemones may look like plants, but actually are animals, and feed by catching edible particles that drift within reach of their tentacles. But being rooted to the sea floor makes them vulnerable to predators. An ocean-going jellyfish, a metre or so across searching for food. The jellyfish senses prey. But it’s the sea anemones that have made the catch and they’ve grabbed a monster. A rare feast for these stationary predators. They devour their catch over the next 4 days.

Life here under the ice has remained unchanged for millennia. But in the last 200 years, much of Antarctica’s wildlife has to face new predators, human beings. We devised new hunting techniques and use them so mercilessly that we almost exterminated the great whales. These whaling stations on South Georgia were at the center of this industry. More than one and a half million whales were slaughtered in Antarctic waters. The blubber was stripped from their massive bodies and boiled down in vats to make margarine and soap. And the largest animal ever recorded, a 33 metres blue whale perhaps over a hundred years old was butchered on this ramp in just two hours. This reckless slaughter marked a new low in our relationship with the natural world.

Southern right whales were hit the hardest. They were so trusting and inquisitive that they swam right up to the whaler’s boats. And the whalers called them “right whales” because they were the right whales to hunt. Mothers with calves were targeted first. To give birth, females came to the same sheltered bays and would not leave their calves alone at the surface. In just decades, a population of 35 thousand was so reduced and only 35 of the females survived. But times have changed, a ban on the commercial hunting of whales introduced in 1986 has stopped all but Japan, Norway and Iceland. Our relationship to these remarkable creatures has undergone a huge shift. Scientists are now learning a great deal about these whales. But we still don’t know how long they live. It’s thought that some individuals alive today were around at the time of the mass slaughter. Yet these 60 tonne whales remain gentle and inquisitive around humans. By putting a stop to commercial hunting, this population of whales has now grown to over 2000. The recovery of life in Antarctic waters may have a significant that extends far beyond the reaches of the continent and will affect us all.

Just off the coast of elephant island, we have recently witnessed what might be the greatest feeding spectacle on earth. On the horizon, over a hundred and fifty whales have gathered to feast on krill. This is the largest congregation of great whales ever filmed. These are mostly fin whales up to 26 metres long. Humpback whales are dwarfed in comparison. Thousands of animals from all over Antarctic waters are making their way here. These seas are once again beginning to brim with life. And scientists have discovered that the southern ocean and the life within it soaks up more than twice as much carbon from the atmosphere as the Amazon rainforest. By protecting Antarctica, we don’t just protect the life here. We’re hoping to restore the natural balance of the entire planet.

Doc 3, 2019

Version 2

By. MZL

Email：muzl0531@163.com