Abyssal zone

The Deep Ocean's Abyssal Zone

The abyssal zone is a very deep part of the ocean. It lies between 4,000 and 6,000 meters (13,000 and 20,000 feet) below the surface, where it is always dark. This zone covers a huge area—about 83% of the ocean and 60% of Earth's entire surface.

Because there is no sunlight, plants cannot grow here. The water is very cold, staying around 2–3 °C (36–37 °F), and the pressure is extremely high. Most of the oxygen in this zone comes from ice that melted long ago in the polar regions.

The abyssal zone is an important part of the ocean. It has lots of nutrients such as nitrogen, phosphorus, and silica, which come from dead animals and plants that sink down from the shallower parts of the ocean. Below the abyssal zone lies an even deeper area called the hadal zone. Above it is the bathyal zone.

Amazing Creatures

The abyssal zone is home to many fascinating creatures. Some interesting animals include the tripod fish, which stands on long bony rays. The Dumbo octopus, named for the ears on its head, hovers above the sea floor. The cusk eel lives at amazing depths and uses special organs to sense its surroundings. The abyssal grenadier has huge eyes to see in the dark, and the Mariana snailfish lives in the deepest parts of the ocean.

These animals have changed to survive in the cold, dark, and high-pressure water. They have slower metabolisms and move slowly to save energy because food is hard to find. Many of these animals can make their own light through a process called bioluminescence. This light helps them see and hide in the deep sea.