9:33
From the frozen shores of the Canadian Arctic to the tropical reefs of Costa Rica, North America is a land of extremes. It's going to be a chilly one. With temperatures ranging from -60° C to + 50, no continent on Earth presents such variety of challenges for marine life or opportunity. Wow. The largest animal on Earth is just what, 40, 50 m away from the boat here. I'm spending a year exploring the coastline of this continent. Meeting the life that calls it home and investigating the challenges it faces from us humans.
Others waited a little too long and some didn't survive. Join me as I explore the most extraordinary coastline on the planet. This is one of the best mail encounters I've ever had. My first adventure takes me across the northwest of this vast continent and through the Alaskan wilderness. As a biologist, I'm fascinated with how nature rises to the challenges facing it. And for me and many of the creatures living up here, the main challenge is the cold. It's uh 400 p.m. I've been out all day and it's -4.
It is freezing, but I've got to keep moving if I'm going to reach the coast. I've timed my journey to coincide with the end of winter and the dramatic arrival of spring. In a few months time, this place will explode into life. But right now, it's March. I just seen no life at all. Not even any tracks in the snow. And believe it or not, this is actually quite a warm day. Temperatures in the interior can plummet down to -40° C. It seems like such a desolate and quiet place here. But out there in the ocean, the story is quite different. The waters around the south of Alaska can drop to zero at this time of year.
It's going to be a chilly one. It's only the high levels of salts that stop it from freezing. Without this dry suit, I'd only last a few minutes before hypothermia would set in. But despite the cold, I'm met with a kaleidoscope of color. Here, cold, nutrientrich water supports a bounty of life all year round. As far as I can see, sponges and urchins dominate the rocky shoreline and provide a home for a vast array of life. Large plumos anemmones are as beautiful as any coral, but they're actually hunters with stinging tentacles that grab anything that comes too close.
These underwater forests provide shelter for even more fish. But I wonder how all this life survives in such bitter temperatures. Many of the fish, like this sculpin, have an antifreeze in their veins. It keeps ice crystals that come through its gills from growing, allowing it to thrive where others would freeze. But where there's this much life, predators are never far away. Stellar sea lions. An unexpected surprise. At twice my size, they're the largest sea lions on the planet. And as they come to check me out, I can feel my heart beating faster. But it's this immense bulk and a thick layer of blubber that helps them cope
with the cold. Once they realize I'm not a threat, they begin to play. I can feel their power as they jostle me. They're so fast and graceful. I'm reminded that here I am very much a land animal entering their world. Staying warm in these frozen seas requires a lot of energy. They'll feed on anything from starfish and crabs to octopus and squid to eat around 6% of their body weight every day. That's like me eating eight loaves of bread. Their whiskers brush my face as they dance around me. These whiskers allow them to sense and capture prey even when winter storms churn up the water and the visibility is only a few cm.
It's one more vital adaptation that allows life to survive in these northern seas. Oh my gosh. That was honestly incredible. I have never seen so many sea lions in one place. It was like a tornado of sea lion bodies. You're just boiling in the water. It's incredible. Oh god. You know, I've done lots of diving in cold water, but I have never experienced anything like that. I'm just in awe of how elegant and graceful they are underwater. And you know, despite the fact that I can't feel my face, I'm so
cold and it's so freezing, these animals are just they're so well adapted and so incredible to see that closeup up under water. It's just awesome. Hands down, one of the best dives I've ever done. My first stop on my journey around North America is the Illusian Islands. It's a place so remote there's more wildlife than humans. There's one on a house here, three there, one on this lampost. There's another one and another. This is crazy. The port town of an Alaska sits on the top of a massive underwater volcano.
These volcanoes turned islands were once a part of Russia, but were purchased by the US in 1867. And today they're actually now home to the highest density of bald eagles seen anywhere on the planet. They are literally like giant pigeons. They are everywhere. The eagles are taking up position on every prime bit of real estate in an Alaska. In the summer months, bald eagles will actually expand their territory into the Alaskan interior. But in the winter, they'll take refuge in places like an Alaska because this is where the food is. And when they're concentrated like this, it's a great time to film them.
Wow. God. When you see them soaring like that, you really appreciate their size. And that wingspan is as wide as I am tall. And they use those giant wings to be able to soar up on those thermals so elegantly. I think this one might actually be going in for a bit of a dive. This is the thing about bald eagles, you know, they're able to spot fish from, you know, up to a kilometer up in the air with their incredible eyesight. And when they go onto that dive, tumbling through the air before going in with those giant talons.
God, they are just incredible to watch. But like many of the animals that survive up here with limited food to get them through the winter, these hunters have learned to take advantage of every opportunity that comes their way. Fisheries biologist and local resident Brianna McGrath knows these seasonal visitors well. When people think of the bald eagle, they think of this kind of majestic predator, but it's slightly different here. It's quite unique town in that way. Hey. Yeah. So, I would say that there are definitely supreme scavengers here in this town. We've had one or two in our chip supply here, our local supermarket. In the supermarket.
Yeah. Okay. Yeah. Thankfully, not very often. And we've had them in like frozen warehouses, processing plants, into even our crab tanks. Um, and I've actually had a few get caught inside of these crab pots. Okay. They're literally everywhere. Yes. Okay. But the crafty eagle's antics can get them in trouble. Brianna spends her spare time rescuing birds that get injured during their scavenging escapades. They're quite a large and territorial bird. Do you have to be careful and aware of them? Yeah, there's actually signs around town and that says, "Beware eagles."
They could be a pest to fishermen particularly. They hang out on the boats and on the docks and eat a bunch of their fish. This is one of the biggest fishing ports in the country. And eagles love fish. Oh wow. It's really strange actually seeing such a majestic and iconic bird. Literally the symbol of the United States. just scavenging here on this fishing vessel. But it makes sense, you know, in order to survive in these really hostile conditions, you have to be able to adapt and make the most of every opportunity, even those ones presented by humans. This ability to adapt and be opportunistic is exactly what bald eagles do so well and why they thrive here on this frozen corner of
the continent. As I leave an Alaska, I notice it's not just the eagles that are depending on this town to help them through winter. Red foxes are also on the lookout for an easy feed, supplementing their hunts with anything they can scavenge off humans. Leaving the Illutian Islands behind, I head east and straight into a storm. There is snow flying around everywhere. These winds are howling. It's literally shaking the SUV. And between the winds and the icy roads, I'm barely able to keep this car straight.
Even the hardy eagles are hunkering down. Their thick down feathers are keeping them warm in these icy winds. Winter storms in Alaska are frequent. They're unpredictable and notoriously powerful with speeds reaching up to 200 kilometers an hour. But strangely, these winds are actually critical for a lot of the life that I've witnessed in these oceans. Extreme snow, wind, ice, and rain erode the mountains in Alaska's interior, depositing millions of tons of nutrientrich sediment into the rivers. And from here, it runs all the way to the ocean. This keeps Alaska's coastal waters full of nutrients and
actually lays the foundations for an annual explosion of life. It's May and spring has finally arrived in the north. As the days get longer and the sun starts to warm the waters around Alaska, something remarkable happens. The water explodes into life. As billions of tiny aquatic plants and animals thrive on the warming conditions, blooming on a scale so large they can be seen from space. They attract visitors from far away to a brief annual feast. Most of them have spent the winter further south in warmer seas, timing their return perfectly.
along the coast. Grizzly bears are emerging into the light. They've avoided the worst of the winter in their dens, but haven't eaten for 8 months and are hungry. They'll scavenge on anything that's washed up with the tide. and if they're lucky, catch some of the fish that are beginning to gather in the shallows, ready to spawn. Like the whales, they now face a race against time to feed as much as they can in this fleeting summer window of just four short months.
Even in the very far north of Alaska, the sea ice that has sealed off the ocean all winter begins to retreat. It reveals rich feeding grounds stocked with krill, a hardy crustaceian that feeds on algae under the sea ice. And it's to the north that I head next, catching a plane over the interior of Alaska to the remote outpost of Utkiadvik. It's in extreme places like this that the spring thor can change an animal's fortunes dramatically. Welcome to quite literally the top of the world. This is one of the most northern settlements on the planet and it's been home to the Inu Piat, an indigenous Inuit group for over 1,500 years living off land and sea.
Even though all this ice has now melted, it is still so cold. temperatures are hovering just around freezing and so the wildlife and the people that live here have to be tough and resourceful. Local biologist Andy Von Duke and his team make the most of this brief window when the polar seas melt. Very little grows this far north. But as we move along the coast, everywhere I look are seabirds. Some, like these Arctic turn, have traveled over 30,000 kilometers from Antarctica to feed on the krill unlocked from the ice. But while this great Thor is an amazing opportunity for some, for others it's a problem.
Polar bears are Arctic specialists and rely on the sea ice to get out to their favorite prey, seals. They're out of sync with anything else at this time of the year when they can't go out on the sea ice. The bears are mainly just trying to conserve energy by uh just uh relaxing and napping and occasionally scavenging on whatever uh stranded marine mammals they can find. To make matters worse, global warming is extending the ice-free period, forcing the bears to extreme measures. An adult walrus can weigh twice as much as a polar bear and comes armed with sharp tusks. But when you're hungry, you have to take risks.
The only way she can succeed is if she can isolate an individual. Pushing them into the shadows. She sees an opportunity. This one's been knocked over as well. Yeah. Definitely I'll have a sample. Yeah. Okay. Andy has been studying the polar bears here for over 10 years. He uses remote cameras and baited posts to collect precious DNA data. They lick the post and uh leave their saliva in there and it's exceptional quality DNA is left. So this black tube here is like a polar bear lollipop essentially apparently. Yeah. Yep.
Placing these posts right along the coast and out on the sea ice. Andy's building a unique picture of the health of the polar bear population here. How many polar bears will you have here at any one time this time of year? They're fairly spread out. So it's um I'd say 5 to 10 in this general area. And so in the time you've been doing this work, what trends have you started to see and how does it look for the polar bears here? Well, as far as population trends, I don't know because uh there just aren't enough estimates out there to come up with an answer to that. But what we're seeing are very
healthy bears. So, for the time being, I feel very good about, you know, how polar bears are doing. But they're having to adapt for sure. Yeah. Determined to see with my own eyes how the polar bears are getting on, we head further into the wilderness. So, we've actually got fresh prints here. Look at the size of them. Uh there's definitely polar bears walking around here. And uh their paws are like dinner plates. So good for swimming. They kind of act like paddles. And uh I see Prince heading that way. Then right at the end of the peninsula, I finally get a glimpse of something.
Picking through the flatsom on a distant island. We've been following these tracks all the way to the water's edge and uh finally to actually get eyes on these polar bears. It's extraordinary. Wow. Okay, this polar bear is sat on top of a walrus. I think this carcass that it's dragging around. It's a really beautiful view because I'm watching them searching for food along this bit of land. And one of the ways they try and get at their prey or trying to break through things, especially these tough bones, is by using their whole body weight. This is a really big animal. So, by jumping on it with their front legs, they're actually able to crush through things like bones and uh Wow.
And it's so dramatic. There's the huge waves pushing in. These polar bears must be about a kilometer away. and they're tiny little dots in a very shaky lens right now with the high winds and the roaring seas, but we actually get to meet the polar bears that Andy is here to study. And uh it's a wonderful way to finish the day. I never actually thought we'd be able to get this remarkable encounter. The animals of the Arctic are facing huge challenges as their habitat warms. But if that isn't enough, they now have new interlopers arriving in their home.
Hi, Lizzie. Hello. Nice to meet you. Yeah. So good to meet you. Um, let's see. Do you want to have that up first? Biologist Kate Stafford keeps tabs on these new visitors. She and her team have been eavesdropping on the ocean, using sound to better understand the marine life here. Always this cold? Yeah. Okay. But it's not always this windy, but it's always this cold. Yeah. Why are you using sound to understand this environment?
Well, one of the best things about sound is underwater sound actually travels much further and more efficiently than sound does in air. And you can see here the water is pretty murky. Sound travels a lot further than light does. And all of the animals in the ocean rely on sound primarily as their main sense. Right. So marine mammals, fish, they use sound to find mates, to navigate, to communicate, to listen for predators. We are listening to the underwater soundsscape and the underwater environment from plankton to whales.
Heading offshore, we see the distant blow of a boowhead whale. They use their thick skull to break the sea ice in the winter, allowing them to get to air where other whales might drown. But like the polar bears, they're facing new challenges as the ice-free period increases and new competitors move in. At the first hydrophone station, we pull the recording device up and download its data. It's a good one. Okay. Yeah. Right. So, so here you should have a listen to this. Hey. Oh, I'm excited. The sounds of bowheads.
These are calls. And you'll also hear some bearded seals in the background. Oh my gosh, I love it. So it's like some real grunts. So almost like bellows. Yeah. And so how loud are these calls from these bowheads? They're pretty loud. Yeah. Um the underwater equivalent. So slightly less loud than a rock concert. Wow. Equivalent. So they're shouting. Yeah. But their calls seem so diverse. It's such like a range of vocalizations that I'm hearing. Yeah, absolutely. And we don't know if the different calls have different meanings.
Okay. It does seem like they use sort of simpler calls offshore and more complex nearshore. They also produce these sounds in um the winter and spring. Okay. Yeah. Song, which is much more elaborate. Wow. Isn't that cool? That is something else. From beluga whales. It's like a big It is. To be honest, it's a whale party. Yeah, it's exactly right. It's awesome. To walrus. What? This sounds like a printer. Kate plays me a cacophony of sounds produced by the marine mammals that have lived up here for thousands of years. Sound looks a bit like a bell.
Yeah. But in recent years, she's increasingly picking up new sounds. We are listening to climate change. So, we are hearing changes in the migratory patterns of both Arctic species, but also these subarctic species who normally would have been excluded from being up here because of the ice. And now with little ice in the summer and fall, humpback whales and killer whales and fin whales are finding new opportunities to feed. They're finding new foraging grounds. Very powerful hearing you kind of talk about it in that way in that you are listening to the new reality and listening to climate change. This is supposed to be the Arctic.
There are animals that are endemic to the Arctic and they're perfectly adapted to live up here. And now these interlopers are coming up who are potentially competing with them for food or thinking of them as food. Yeah. So it's a really rapidly changing ecosystem. We just don't know what's going to happen as we move forward. What an eyeopening day out on the water that was. I'm always amazed at how quickly wildlife is able to adapt and make the most taking advantage of new opportunities and new feeding grounds. And I wouldn't be surprised if before too long there's more species, not just or humpback whales making the most of this. But it's risky. Stay too long, you
may get trapped in that ice and potentially run the risk of not surviving. But time it just right. and now you've got access to incredibly productive seas. It's this ability to be in the right place at the right time that allows life to survive up here. And as I head south again, I'm hoping my own arrival will be right in sync with a true master of the art, the greatest long-distance traveler of all mammals, the grey whale. Are we expecting a bit of a bumpy ride? It'll be a little bit bumpy out there today. To reach my final destination and one of Alaska's most extraordinary feeding events, I catch a ride with sea plane
pilot Tobin Ortega to the remote town of Sitka. That was quite a lot of bump for me. Is that normal? I call this like light job, unfortunately. It can get pretty bumpy around here. That's probably my limit, I'd say, when it comes to turbulence. Alaska's coast is so rugged and inaccessible that sea planes like this are critical to survival of many of its communities. Basically, anything that comes in and out of a lot of these villages comes by air. Okay. Yeah. It's like the lifeline of Yeah. lifeline of a lot of these villages for sure. From up here, you get a sense of how vast this coastline really is. There's
kilometers of inlets and islands, and all along here, there are these hidden spots where different species of fish are getting ready to spawn. But before we can see them, we make a brief stop at the remote village of Tenei Springs to deliver some post. This is the Alaskan way of uh of flying and delivering post. I imagine you see quite a bit of bad weather as well. Quite a bit. Uh we'd mostly deal with low visibility in the winter. We'll get a lot of snow, um hail, and a little bit of turbulence as you're feeling today. Up here, the winters are so harsh and long and the summer's so brief that you really want to make the most of those seasonal feeding events. Above anything else, that's the key to survival up here.
And somewhere down there, I'm hoping to catch the greatest of them all. When I arrive in the remote town of Sitka, the scene is set for a feast like no other. At this time of year, Alaska comes alive. These rich waters are literally bubbling with life, and all these girls have come here on mass for one extraordinary feeding event, and that's what I've come here to see. As I head out to sea with local guide Patrick Davis, beneath the waves, herring are matting on a scale that's hard to fathom. They're here to lay and fertilize their eggs. But their presence triggers the arrival of an oceanic wanderer, humpback whales.
Navigating across the open ocean from the remote waters of Hawaii using sound, smell, and a magnetic six sense, the humpbacks know exactly where and when the spawning will take place. Working together, they herd the herring into tightly packed shoulders. Then blowing air out of their blow holes, they produce a net of bubbles which traps their prey. Desperate to escape, the herring masks on the surface. Then the humpbacks move in for the kill. But despite the many losses, the sheer number of herring means most survive.
The females gather close to shore where they lay their eggs on every available surface. Soon eggs cover every blade of kelp along the shoreline. Sea otterters make the most of this annual harvest while the male herring release sperm into the water to fertilize the eggs. The whole coastline changes color as billions of eggs and sperm are released. Believe it or not, all that yellow on that kind of black volcanic sand is herring eggs. And what's extraordinary is feeding on those herring eggs are two sick of
blacktail deer that are just munching away on that kelp covered in eggs. It's not just the marine animals that are making the most this bounty. There's animals literally emerging out of the forest to capitalize on this spawning event. Humans take advantage, too. The local Clinket people have been harvesting the herring for over 11,000 years, taking both the fish and their eggs. And for the two short weeks the eggs are here, Patrick comes out every day. One's really thick down there, too. So, we got the vine. Look at that, Patrick. That's insane. So, we got the vine. And these are the bulbs.
Okay. So, when you go to harvest these, you leave the bulb intact so it can regrow again. Okay. So you only take off just the flat part like that and leave the bulb. Yeah. How long have you been doing this and eating her? Um since a very early age with my father. Yeah. Very early age. And you were born and raised here. Born and raised right here. Yep. Yeah. So this is a traditional way of harvesting. And this is I mean we've just picked up one piece of kelp and it's absolutely packed.
Yeah. The deeper you go down to the ocean bottom, the thicker that it will be. Yeah. So, is the herring spawn an event that you look forward to every year? Absolutely. Yeah. It's significant. It's a sure sign of spring when the herring come, everything starts to come to life here. The whales come, the sea lions come, everything comes for the har and participates in the harvest as well. What do these actually taste like then? So, they're really crunchy. Mhm. Yeah, they're really crunchy, but when you cook them, they soften up a lot.
Okay. Yeah, this is uh not what I expected. I mean, they talk about billions and billions of eggs spawning here, but I mean, just by this one small piece of kelp, you can see quite how packed this really is. It's extraordinary. Yeah. Kind of blowing my mind to think that every year this happens on a unfathomable scale. But now I get it. Now I get why so much life is drawn to this part of the world for this spectacle. Moving down the coast, we find bay after bay filled with eggs. And I spot familiar faces in the trees.
Ever the opportunists, bold eagles flock to Sikka every spring to take advantage of this event. But their journeys are nothing compared to the migrations of grey whales, which travel over 4,000 kilometers to reach this feast. Oh my gosh, that's incredible. There is a grey whale just along this shoreline here. Could see that really thick blow. Oh, here on the left. It is not every day you get to see an animal as big as a grey whale so close to shore just feeding feet away from that coastline. Wow! One, two, three. There are whole groups of these grey whales all here to feed. You could actually hear the blow that whale is so close. And that's what's so magical about this place at this time of year. You know, big sitations. These
whales like humpback whales and grays are coming to make the most of the herring spawn. But grey whales are different in that they'll be here to eat the eggs themselves. They have a completely different feeding strategy to the humpback. They're of course here for the herring. Grey whales are bottom feeders. So they're diving down into quite shallow waters, but scooping up all those eggs, all that nutrientrich food and anything that comes with it, you know, mud, silt, any substrate down there. And uh as they're coming up to the surface, pushing all of that out through their baine. It's just like that.
I mean, what more do you want? This is just incredible. It's testament to these rich waters that the grey whales have traveled so far to get here. And it's staggering to think as far as they've come, this is only partway through their epic migration. They begin in Baja Mexico, where they give birth to their young. But every spring, when their calves are strong enough, they travel up the continent's western shores to make the most of Sika's rich waters. After this important pit stop, they then head even further north, feeding on different spawning events as they go. Some travel as far as the Illutian Islands, where we saw all those bald eagles and beyond before they finally turn around and head south again. A total journey of over 16,000 km.
It's only their ability to remember where and when to go that allows the whales to survive such an epic migration. But before they head off from Sikka, we follow the grey whales along the coast and get to witness another side to their behavior. What's really interesting here is there's one grey whale, probably a female, that seems to be now traveling and is got two males hot on her tail. And what's really cool is they're all kind of intertwining with each other. I'm literally right above them and they're just rolling around in the waves. This is what grey whales are so well known for. They're socializing.
They're curious and uh really intelligent as a species. So to see this play out is pretty special. Oh my gosh. Okay, I they're definitely mating. Let's just say that this things have become very visible to me on screen that makes it very clear that they're mating. This is awesome. Yeah, I have never seen this intimate behavior playing out like this. This is absolutely extraordinary. Just this is one of the best whale encounters I've ever had.
Unbelievable. To see behavior like that play out so close to you is just so rare. I mean, we're getting the full scope of these lives of these gray whales up here. you know, they're they're feeding. They've spent all the overwintering months, you know, waiting for this feeding frenzy, and now they're here. You get to see these phenomenal behaviors play out. It's Yeah, pretty special. It's a fitting end to my adventure across the Northwest. A land of smart, opportunistic marine life who have come up with so many different ways of coping with the challenges this hostile corner of the continent throws at them.
But now it's time to head south for my next adventure.
