- [Bertie] Only minutes old, this harp seal pup is quick to fall in love with its icy home sweet home. The ice melts. In just 10 days time, mom will leave her behind and never look back. The countdown begins. (baby seal cooing) 10, put on at least four pounds per day. Nine, learn to swim before the ice melts. Eight, don't panic there
is no time for this. Seven, six, five, four, three, two, one. (wind blowing) (daunting music) At first glance the arctic
feel brutally devoid of life. Though a select group of animals have figured out a way to thrive. (seal pup howls) But the real force here
works quietly underfoot. Every winter sea ice
starts small and delicate. Then it grows over
billions of square miles. How is it possible that
this freeze up, holds the key to our entire planet? Like a lung, sea ice
breathes life into the arctic every year. In a cycle that impacts the
climate across the globe. This is the story from the
edge of the Canadian arctic where it all starts. My name is Bertie Gregory and I am a National Geographic Wildlife Filmmaker. Everything is at stake, we are all waiting for the big freeze. (clock ticking) (calm music) Every year, harp seals
leave the rich waters of the northern Hudson Bay and join thousands of other migrating south
out of polar bear range to their breeding oasis. A massive ice flow in the Gulf of St. Lawrence. (flute music) (snow crunching) It is hard to believe right now, that we are walking over the ocean. Everywhere you look as
far as you can see is ice. That is the reason why I
have got this incredibly sexy and very fashionable
outfit on and a stick, is 'cause we want to make sure we
don't fall through a crack in the ice, into underneath us
which is hundreds of feet of freezing cold water. But right now we are looking for what is arguably the cutest animal on the planet. (seal pup cries) And I can hear it. (flute music) This beautiful little animal,
hello, is a harp seal pup. It was born here on the ice
about four or five days ago judging by its size. It is totally helpless without mom right now. (water bubbling) (flute music) (seal chirping) In a colony of thousands, mom needs to make sure she
is not feeding the wrong pup. Here she comes. The kiss, this what harp seals are famous for, that kiss is how the mom and pup recognize each other. (seals cooing) This is what that little pup has been waiting for. It is dinner time and it has really got to make the most of these
feeding sessions because its has only got 10 days with its mom. After those 10 days, the female
is going to stop suckling the pup, and she is going to
head north with the males. That little pup is going to
be abandoned with nothing to eat. So it has really got to build
up its fat reserves now. Since filming that pup, I have found something that is a little bit gross. So you see down here,
there is this blood trail. It leads to this. Now this looks like death but it is not, this is life,
this is the placenta. But it is not actually frozen yet. That means that somewhere around here, is a new born pup that has literally just been born. I mean that would take less than an hour to freeze,
so somewhere here, is that little pup. Look, there it is. Yeah, that one is just a few minutes old. Look how yellow it is and you can still see it has got its umbilical cord attached. You know compared to that
other pup we had which was only a few days old, four
or five days older, this shows just how fast they grow and this little pup has definitely got some catching up to do. (tribal music) You know it is really cool
to see such a young pup but it is actually not a good thing. This one is four or five
days behind the rest and these adults are already
in a race against time to raise their pups before
the ice breaks up so this one has an extra big challenge ahead. (violin music) (seal pup whimpers) (violin music) [Bertie]
Our changing climate is making early ice breakups
more and more common. In five of the past ten years bad ice meant the colony failed to raise pups. In 2017 the ice broke up so early that the entire colony of pups drowned overnight. (fast violin music) So you can see what was
once a giant solid sheet is now breaking up and the ice
is really on the move, you can see it. Here now, it is the time for
these pups to learn to swim because soon these chunks
are going to get smaller and smaller and uh, and yeah
they will be forced to swim. So it is swimming time they got to go. And that is exactly
what is on this mothers mind right now. This real chunky monkey is
so fat it is unbelievable the amount of change
just in a few days from that tiny little new born,
now to a big fat sausage. So we are going to hang out
and see if mom encourages it for its first swimming lesson. (cello music) (seal pup cooing) (seal pup whimpers) Are we good to go? - [Cameraman] Yeah (flute music) (seal pup cries) (seal pup cries) - [Bertie] Look how she
is using her giant belly as a big swim float to help her pup breathe. You can see she is so
protective of it in the water. And anytime any of the
other adults come anywhere near her she chases them
off so aggressively. It is really doing it, its swimming. Look at it go. (flute music) How incredible must it be to realize you are actually built for the very medium that was so daunting just minutes ago. Now that the mother knows
her pup has the skills to survive the ice breakup,
it is time for the hardest lesson of all. Saying goodbye. (seal pup howls) The male harp seals are
now gathering nearby. Ready to mate with the females. Okay, getting in. It is time for the adults to
join and head to the north. (seals chirping) (violin music) We have met truly extraordinary animals on this adventure. surrounded by the pack. Their lives governed by
ticking clocks getting them to run further, fly faster or swim deeper. But the thing that ties
them and us together is the planets loudest ticking clock. The arctic sea ice. The big freeze used to give
us millions of square miles of sun reflecting surface,
stabilizing the earth's climate. Over just the last thirty
years, we have lost more than a third of that sea ice. Now rather than reflecting the suns heat, open water absorbs it. And we are witnessing its deadly effects. (violin music) But there is hope and it lies with harnessing
clean energy, using our land more efficiently and reforesting. Saving polar bears go beyond
just a nice thing to do, we are also saving ourselves. It really is in our hands
whether we want this place to exist in the future. Now is really a turning point. Do we let it go or do we really band together
to make sure that it survives into the next century? (orchestral music) (piano music)
