Pelagic zone facts for kids
The pelagic zone is a huge part of the ocean. It's the open water far from the coast or the sea floor. Think of it as the wide-open ocean, where you can't see land or the bottom. The word "pelagic" comes from the Greek word pélagos. This word means "open sea."
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Ocean Layers: The Pelagic Sub-zones
The pelagic zone is divided into different layers. Each layer has its own unique features. These layers are based on how deep they are and how much light reaches them.
Epipelagic Zone: The Sunlight Layer
The epipelagic zone is the top layer. It goes from the surface down to about 200 meters (656 feet). This zone gets a lot of sunlight. Because of the light, tiny plants called plankton can grow here. Plankton are the base of the ocean's food chain. Many animals, like tuna and different types of sharks, live and hunt in this sunny zone.
Mesopelagic Zone: The Twilight Layer
The mesopelagic zone is the next layer down. It stretches from 200 meters to 1,000 meters (3,280 feet) deep. This layer is often called the "twilight zone." Some sunlight reaches here, but it's not enough for plants to grow. The name "mesopelagic" comes from the Greek word for "middle."
Bathyal Zone: The Midnight Layer
The bathyal zone is very deep, from 1,000 meters to 4,000 meters (13,120 feet). It is almost completely dark here. You might see a flash of light from a bioluminescent animal. These animals make their own light. There are no plants in this zone. Most animals eat tiny bits of food falling from above. This falling food is called "marine snow." Giant squid live here and are hunted by deep-diving sperm whales. The name comes from the Greek word for "deep."
Abyssal Zone: The Abyss
The abyssal zone goes from 4,000 meters down to the ocean floor. No sunlight reaches this depth at all. Some creatures here are blind and have no color. They don't need eyes or color in the total darkness. Bioluminescence is also common in this zone.
Hadal Zone: The Deepest Trenches
The hadal zone is the deepest part of the ocean. It includes the water found in ocean trenches. These are like huge canyons in the sea floor. The name comes from Hades, the Greek underworld. This zone is still a bit of a mystery. Not many species live in the open water here. However, many unique organisms live around hydrothermal vents. These are like hot springs on the ocean floor.
Some scientists group the deepest three zones together. They are all very dark and cold.
Images for kids
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Some representative ocean animals (not drawn to scale) within their approximate depth-defined ecological habitats. Tiny Marine microorganisms also exist on and within the bodies of ocean life. Animals living on the ocean floor are called benthic animals, not pelagic.
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The pelagic wandering albatross (Diomedea exulans) flies over huge areas of the open ocean. It can even fly around the world!
See also
In Spanish: Piélago para niños