The neritic zone is the top-most layer of the ocean that surrounds the world’s coasts. In this lesson, we’ll discuss the characteristics of this zone, what lives there, and what its climate is like.
What Is the Neritic Zone?
Have you ever seen images or a video of scuba divers or snorkelers exploring colorful, clear waters filled with fish and other sea life? Maybe you’ve even been one of those adventurers yourself.
Well, even if you haven’t, you’re in luck, because today we’ll be exploring the beautiful top layer of the ocean that is the neritic zone. The name might not sound glamorous, but the neritic zone is home to much of the sea life we picture when we think of the ocean. The neritic zone is also referred to as the coastal waters because it’s the shallow waters close to the coast.The neritic zone extends from the surface of the water to about 200 feet below, where the sea floor, or continental shelf, sits. As the sea floor extends away from the shore, eventually the continental shelf drops off, creating much deeper waters and leading to the open ocean. The neritic zone only occurs before the continental shelf drops off.
Climate of the Neritic Zone
Since the water is so shallow, the neritic zone receives ample sunlight.
The water temperatures tend to be relatively stable as well, but the temperature is different depending on what area of the world the zone is in. For example, the neritic zone of the Arctic Ocean is much colder than the neritic zone found in tropical areas, such as off the coast of much of western Africa.The salinity, or amount of salt, in this part of the ocean is also stable, which helps to support the diverse life found there. The pressure is similar to that of the surface, so that isn’t a concern for life in the neritic zone, either. Other, deeper parts of the ocean have extreme pressures due to the water above that prevents a lot of life from flourishing.
Sea Life in the Neritic Zone
Since there’s a lot of sunlight in the neritic zone, green plants grow there, providing a high oxygen content to support the brilliant sea life we often see in its shallow waters.
The neritic zone is the most productive area of the ocean and is home to thousands of fish species. The more tropical areas contain especially high numbers of fish species, as well as thick coral reefs teeming with biodiversity.The most famous of these coral reefs is the Great Barrier Reef off the coast of Australia. This reef is home to over a thousand unique species of fish and coral. Over one hundred species of sharks live here, such as the strange hammerhead shark. Sea snakes, some of the most poisonous snakes in the world, also live in this zone, and some are found nowhere else in the world, such as the banded sea snake.
The neritic zone occurs in all coastal areas. In colder climates, such as the waters off the coast of Alaska, the sea life changes, and the neritic zone looks different than in tropical areas. The neritic zone is still home to many species of plants and animals, but they are adapted to the cold. Different key kelp species support crabs and other shellfish that, in turn, support large fish, such as the sockeye salmon, which migrate to the neritic zone to spawn.
Larger, familiar mammals such as sea otters and some species of whale also inhabit the neritic zone in northern waters, however, so do rare and unique animals like the giant octopus. This magnificent neritic dweller can grow to weigh as much as 600 pounds from its original size of roughly a grain of rice when it hatches.
Clearly, the neritic zone is a flourishing habitat with a lot of biodiversity. The shallow waters, starting from the surface and extending down about 200 feet to the continental shelf, are home to thousands of unique species. The neritic zone extends from the coast to the end of the continental shelf around all the coasts of the world.
It has a stable climate with high oxygen content, plentiful sunlight, and consistent salinity. The neritic zones in tropical climates, like the Great Barrier Reef in Australia, are home to thousands of species of sea life, such as coral, sharks, and sea snakes that are found nowhere else in the world. Northern neritic zones are also flourishing with sea life, including sea otters, whales, and the giant octopus.