Mysterious Sea Creatures

Have you ever stood by the sea and wondered what is down there in the dark depths? We have actually mapped more of the surface of Mars than of our own ocean floor. That means we know more about a planet 200 million kilometres away than about the world just below the waves! And in those unknown depths live creatures that seem to come straight from a fairy tale. Let us dive down and explore them.

Let us start with one of the ocean's eeriest and yet most fascinating animals, the anglerfish. It lives in deep, dark water, sometimes more than one kilometre down. It is pitch black down there, and there is almost no light. But the anglerfish has solved that problem in a very clever way: it has a small glowing lantern that hangs in front of its nose like a fishing rod, with a glowing lure on the end. That light shines into the darkness and attracts curious fish, and then the anglerfish catches them.

The anglerfish's glowing lantern is an example of something called bioluminescence, that is when living creatures make their own light. In the deep ocean, bioluminescence is much more common than you might think. In fact, more than eighty percent of all animals living in deep water can glow! They use the light to attract prey, communicate with each other, or scare away enemies. It is as if the whole deep-sea world is lit up with millions of tiny lanterns.

Now let us look at one of the ocean's true giants, the giant squid. It can grow up to thirteen metres long, that is longer than a large bus! The giant squid has some of the largest eyes of any animal, each eye can be as big as a dinner plate. Those huge eyes are needed to catch the faint light in the darkness of the deep ocean. For a long time, the giant squid was only a legend, sailors told stories of a monster that could sink ships. But it is a real animal, and it is fascinating.

There is actually a squid even bigger than the giant squid, the colossal squid! It can be heavier and more powerful, and it has eyes that are roughly the size of footballs. Those are absolutely the largest eyes in the entire animal kingdom. The colossal squid lives deep in the cold seas around Antarctica and is extremely rarely seen. Most of what we know about them has been learned from the stomachs of sperm whales, the only animal that dives deeply enough to meet them.