The epipelagic zone extends from the sea's surface to 200 m and is home to the most biodiversity, owing to the abundance of sunshine that allows photosynthetic species to thrive. Here you may find both sea flora and animals. The photic zone below 200 m is called the mesopelagic and it too is rich in life, though mostly unseen by humans. The bathypelagic zone reaches down to where the pressure becomes so great that no water can escape, making any living matter there invisible to us.
The total area of all oceans is 4 million km2 (1.5 million sq mi). Oceans cover 70% of Earth's surface and are important for life on land as well as at sea. They play a major role in climate regulation by absorbing carbon dioxide from the atmosphere and storing it in their waters. They also contain 70% of all the water on Earth and ocean creatures make up half of all known living organisms. There are more species alive today than ever before - an estimated 9 million - with another 1 million discovered every year.
Oceans contain a huge variety of habitats, from shallow beaches with waves washing over them daily to deep trenches cut by rivers flowing into the sea. Other interesting features include coral reefs, islands, and large lava fields covered in vegetation.
The epipelagic zone extends from the ocean's surface to around 650 feet. This is the zone most exposed to light, and as such, it has the greatest densities of marine life. This zone is home to countless of creatures, including dolphins, most sharks, jellyfish, tuna, and coral. It can be divided into two sections: the mesopelagic (middle deep) and the bathypelagic (deepest deep).
The mesopelagic zone begins at about 650 feet and goes down to 12,500 feet. Most fish and other animals that live in this zone make their living by eating smaller particles or chemicals in the water. Some species may also eat plastic or other materials that have been dumped into the sea.
The bathypelagic zone starts at about 12,500 feet and goes all the way to the Earth's core-mantle boundary. Animals that live in this zone are mostly cold-blooded and include turtles, snakes, fish, and mammals. They make their livings by hunting for food like shrimp, crabs, worms, and other small organisms.
Overall, the oceans are a big place with many different environments. Each zone has its own unique characteristics that allow certain species to thrive. For example, the mesopelagic zone is home to many large predators such as tuna and sharks because there are not many other things around to eat them.
Epipelagic The epipelagic or photic zone is the topmost zone, extending from the sea surface to a depth of 200 m (656 feet). Because of the abundance of accessible sunshine, this is the most productive zone of the ocean. Fish and other organisms live here in great numbers. Crustaceans include shrimps and crabs that get their name from the fact that they often cover themselves with rocks when threatened, which makes them useful for building a home. Mollusks include clams, snails, and octopuses, who share some characteristics with fish because they also have spinal columns made up of bone and muscle. Echinoderms include stars and sea urchins. They are covered in spines and can grow to be over a meter long.
The epipelagic zone is where most marine species live. There are several reasons for this: light penetrates deep into this layer, making it rich in nutrients; it is also warm near the surface and cools down rapidly with depth; finally, there are few predators in the epipelagic zone. Many large animals migrate between different parts of the ocean looking for better food or warmer waters during cold seasons or hurricanes. Humans affect the productivity of the epipelagic zone by removing large animals such as whales for oil and other products, and small animals for food and money. Removing these key species affects the ecosystem and can cause it to become unstable.
The epipelagic zone In general, coastal environments are abundant in aquatic life. The epipelagic zone is home to the majority of life in the open ocean. It extends from the surface to about 200 meters (660 feet) below sea level and comprises all of the water above the pycnocline. This zone is divided into two main sections: the euphotic zone, which is the part of the epipelagic zone that is light enough for photosynthesis to take place; and the aphotic zone, which is the part of the epipelagic zone that is dark enough for no sunlight to reach. Within the euphotic zone, there is a great diversity of organisms living at different depths. Fish tend to be more common near the surface while deeper down you will find cephalopods (squids and octopuses).
Fish are very important for maintaining balance in marine ecosystems because they are prey for many larger animals including sharks, whales, and birds. They also provide food for other smaller fish, seaweeds, and insects. There are several types of fish found in high concentrations in the epipelagic zone. For example, almost all shark species live in this zone, as do half of all known fish species. Many rays and skates also make their homes here.
In general, this zone extends from the sea surface to a depth of around 200 m. (650 feet). Many iconic creatures live in the epipelagic, including whales and dolphins, billfish, tunas, jellyfish, sharks, and many others. The mesopelagic is even more mysterious; it's below 200 meters (660 feet) and contains an enormous diversity of animals that few people have ever seen.
The bathypelagic is even deeper. It reaches down to thousands of feet beneath the surface and is home to even more exotic creatures. Here you will find giant squid, vampire squid, octopuses, fish-eating spiders, and many other bizarre creatures.
Deep-sea habitats are extremely diverse. Each layer has its own unique conditions: sunlight intensity changes as you go deeper, water pressure increases, and temperature drops. These factors affect what life can survive in each zone. For example, no fish have been found living above 930 meters (3200 feet), but many mammals, birds, and reptiles do live here.
Many species are known only from one or two specimens collected in deep waters. Scientists use information about these rare animals to build up a picture of how many species there are in the ocean.