字幕表 動画を再生する 英語字幕をプリント [intro] Goodness, it's cold today. I'll turn up the heat in here, but maybe we should start up the Fort's fireplace, too! It's winter in lots of parts of the world, and that means lots of cold … and for some animals, a very different world outside than in the summer. One of the places where things are the most different is the Arctic, the part of the world near the North Pole. That's at the very top of the globe. When it's winter in the Arctic, it also becomes the coldest part of the world. Now, I don't know about you, but I like to be warm. [Squeaks agrees] But for some of the animals that live in the Arctic, the super-cold winter is actually a great/thing. Like polar bears! They have a much easier time finding food in the winter because of all the sea ice. In the winter, the Arctic is so cold that almost all of the ocean up there freezes into a layer of ice at the top. For polar bears, that's awesome, because they like to hunt seals. Seals are big and round, and they have flippers instead of legs. So they can move around on land, but they're very slow – way slower than a polar bear. That means if a polar bear can get a seal out of the water, they have a good chance of catching them. The thing is, seals spend most of their time underwater, not on land or on top of the ice. And even though polar bears can swim a bit, they're nowhere close to as fast as a seal underwater. If they tried to hunt a seal in the water, the seal would swim away pretty easily. [Squeaks asks: so how do they catch them?] That's exactly the problem! During the warmer parts of the year, it's very hard for polar bears to catch seals. But when there's lots of sea ice around, polar bears have a really smart way of hunting them. See, even though seals spend so much time underwater, they do need to breathe, just like we do. So they have to come up for air sometimes. In the summer, that doesn't make too much of a difference to polar bears, because a seal could come up for air basically anywhere. Even if a polar bear tries to chase them, they can just dive back into the water and swim away. But do you remember what's different about the Arctic ocean in the winter? [Squeaks answers: ice?] That's right, there's all that ice covering the ocean! To breathe, the seals have to make holes in the ice that they can use to pop up when they need some air. So all a hungry polar bear has to do is hang out near one of these holes, wait for a seal to come up, and grab them! They can do this for most of the winter. Some polar bears live in parts of the Arctic where the ice never melts completely, so they can hunt this way the whole year. In the spring, when the ice starts to melt in most of the Arctic, polar bears still have an easy way to get seals for a little while. The spring is when seals have their babies, and they stay on top of the ice until they're old enough to swim. That makes it easy for polar bears to catch them. By the time the summer comes around though, the seals are back in the water, and the polar bears have to wait until it gets colder again before they can hunt more seals. It's a good thing the bears get lots of food in the winter and spring, because some of them don't eat at all for most of the summer! Polar bears aren't the only animals that are good at finding food in the winter near the North Pole. Seals are also great at it, since they can do basically the same thing they do the all year -- just dive under the water and catch things like fish and squid. And walruses, which look kind of like giant seals with long tusks, do the same thing. Arctic foxes are pretty good at finding food too. They hunt lemmings, little animals that spend the winter in burrows under the snow. To find them, the foxes sniff around until they smell lemmings. Then they dive into the snow and dig until they catch one! But one of the things that makes polar bears special is that it's so much easier for them to hunt in the winter than it is in the summer. Near the North Pole, these super-cold months are a great time to be a polar bear! Thanks for joining us! Do you have questions about the North Pole, or polar bears, or anything at all? We have a website where you can send them to us! Just ask a grown-up to help you go to patreon.com/scishowkids to check it out. We'll see you next time, here at the Fort! [ outro ]