Ocean Facts for Kids
Deep-sea facts and ocean wonders
Ancient Polynesian navigators could cross thousands of kilometres of open ocean without any instruments by reading the stars, ocean swells, wind patterns, and even the behaviour of birds. This extraordinary knowledge was passed down through generations.
Sound travels about four times faster in water than in air, which is why submarine sonar systems and whale calls can carry across enormous distances. Blue whales produce the loudest sound of any animal on Earth.
The Greenland shark is the longest-lived vertebrate on Earth, with some individuals estimated to be over 400 years old. They grow incredibly slowly, reaching sexual maturity only at around 150 years of age.
Sea snakes can absorb up to 33% of their oxygen directly through their skin while submerged, allowing them to stay underwater for hours at a time. Their flat, paddle-shaped tails make them excellent swimmers.
Sediment cores drilled from the ocean floor contain a detailed record of Earth's climate stretching back millions of years. Scientists read these layers like the rings of a tree to understand how the climate has changed over time.
The cone snail hunts fish and other animals by shooting a tiny venomous harpoon from a flexible tube that can extend in any direction. Some species are venomous enough to be dangerous to humans.
The blue sea dragon is a tiny sea slug only about 3 centimetres long that floats on the ocean surface and feeds on the venomous Portuguese man o' war. It concentrates the stinging cells from its prey and can deliver a painful sting itself.
In 2021, National Geographic officially recognised a fifth ocean — the Southern Ocean surrounding Antarctica — giving it the same status as the Pacific, Atlantic, Indian, and Arctic Oceans. It is defined by a powerful current called the Antarctic Circumpolar Current.
Barnacles attach themselves to the skin of humpback whales and hitch a ride across the ocean without harming the whale. A single large whale can carry up to half a tonne of barnacles on its body.
Horseshoe crabs have blue blood containing a substance called Limulus Amebocyte Lysate, which is used by the medical industry to test that vaccines and medicines are free of dangerous bacteria. These ancient creatures have barely changed in 445 million years.