The world’s oceans are divided into five sections – the Pacific Ocean, Atlantic Ocean, Indian Ocean, Antarctic Ocean, and the Arctic Ocean. Before the year 2000, only four oceans were recognized officially by the International Hydrographic Organization, but the entity added the Antarctic Ocean (also known as the Southern Ocean) that year.
Oceans make up 71% of the Earth’s surface, and they exclusively hold saltwater. These oceans are only home to marine creatures, and there are no oceans in the world that are the primary home to any land-dwelling animals. Every area of the world has unique and colorful species of fish, mammals, and other wildlife. The ocean is a crucial part of the world’s ecosystems, and researchers have openly admitted that approximately 80% of the oceans are still unmapped and unexplored in 2021.
Where to Find the Ocean Animals
Our water bodies around the world are known to be homes to diverse and unique ocean animals and other wildlife. Most wild marine creatures are spread out across the world and are known to reside in different oceans. The Pacific Ocean is home to:
Hammerhead sharks. These sharks can weigh up to 1,000 lbs., and they have one of the most distinctive bodies of any shark.
Giant squids. The Giant squid is the largest invertebrate found on Earth so far. It can grow up to 33 feet long.
In the Indian Ocean, you’ll find:
Indian river dolphins. These dolphins have terrible vision, and they primarily live in the few areas of the world with fresh water.
Goonch catfish. Typically found around India and Nepal, these fish are one of the largest types of catfish in the world.
The Arctic Ocean is known for the brisk waters that animals already have to survive in, but it still manages to contain:
Pacific walruses. This type of walrus was once considered an endangered species but was denied the classification in 2017.
The Southern Ocean, which is more commonly known as the Antarctic Ocean, is rather diverse, residing at the southernmost point of the world. It was only officially recognized by the International Hydrographic Organization in 2000. Some of the most common animals in this region include:
Cuttlefish. These fish can be kept as pets, though they have intricate needs to keep the invertebrate healthy.
Colossal squids. This squid is larger than the giant squid, and it is only found 2,000 meters below the Ocean’s surface.
The Atlantic Ocean is home to a diverse group of animals as well, including:
Porpoises. Looking fairly similar to a dolphin, this animal only lives for about 10 years.
These are only some of the animals that you’ll find in oceans around the world. So much of the world’s oceans have yet to be explored beyond a certain depth, so it is likely that many other animals lurk beneath the surface.
The Most Dangerous Ocean Animals
No matter how calm the ocean water looks at the surface, a lot can always be going on inside it. There are several dangerous animals inside the ocean at any given point in time. These include:
Pufferfish: A pufferfish might contain deadly toxins that can be severely dangerous. It can make you gravely ill and can also be potentially lethal.
Lionfish: This fish is venomous, and it is primarily found in the Caribbean.
Sea snakes: The bite of a sea snake can be fatal, which is why they are considered to be dangerous especially for anglers.
Tiger sharks: Tiger sharks are known to attack humans unprovoked and can tear out the flesh with their specially designed teeth.
Box jellyfish: The bodies of box jellyfishes have tiny darts that are loaded with poison. Once stung by them, humans and animals can experience cardiac arrest, paralysis, or even death.
Considering how much of the world’s oceans still are hidden from access (due to their depth), it is likely that many more dangerous animals are still around. Perhaps the most dangerous part of these waters is that animals may be waiting to attack if anyone decides to go beyond what is already known to scientists.
Despite the wildlife and ocean animals around the world being diverse and unique, there is always a threat to these animals being endangered or extinct. In fact, approximately one-third of the animals in oceans today are currently endangered. Some of these endangered animals include:
Pollution is a major threat to marine creatures around the world. As many as one million animals are killed each year from the trash and other debris that humans leave behind in the ocean. Conservation efforts are being made by companies like Ocean Conservancy and Oceana.
As of 2015, 15 different animals have got extinct so far, including the great auk and the Caribbean monk seal. Most of the animals were never photographed, leaving researchers only to guess what they may have once looked like.
Ocean Animals: Birds
While there aren’t any birds that live in the ocean, there are many different types of birds that inhabit coastal shores or spend most of their time at sea.
Types of seabirds include:
Penguins: There are 18 species of penguins, almost all of which are found in the southern hemisphere. The only exception is Galapagos penguins. Penguins live in a variety of habitats, from Galapagos penguins on tropical islands to emperor penguins in the Antarctic. Most species live somewhere in-between. They are all highly specialized for marine life.
Petrels: Petrels are pelagic birds, meaning they spend almost all of their time at sea. They only return to land for breeding. Petrels are found in all oceans. Most species reside north of New Zealand. There are four main groups of petrels; prions, shearwaters, fulmarines, and gadflys. Breeding and migration vary based on species and location.
Pelicans: Pelicans are native to all continents except Antarctica. There are eight living species of pelicans. Not all pelicans migrate, some populations stay on coasts year-round. Others migrate to warmer climates during breeding season.
Gulls and Terns: Gulls and terns are closely related and have similar lifestyles. They spend breeding seasons on coastal or offshore islands and take to the open sea during non-breeding seasons. Some species are pelagic. Terns inhabit all continents except for Antarctica, while gulls are found worldwide.
Types of Fish In The Ocean
Fish inhabit every ocean and nearly all marine habitats and oceanic zones. There are an estimated 20,000 species of fish in the oceans around the world.
Most people don’t think of snakes when they picture the ocean. In fact, there are 69 species of snakes native to the ocean, almost all of which are venomous. There are two groups of sea snakes, also known as coral reef snakes; true sea snakes, and sea kraits. Sea kraits don’t have as many adaptations for marine life. The bodies of true sea snakes have evolved for a life completely in water, while sea kraits can go on land. True sea snakes even give birth in water. Sea kraits lay eggs on land.
Sea snakes are found in tropical waters between the Indian and western Pacific Oceans. Most of them live in coral reefs and estuaries. The yellow-bellied sea snake is the only species that lives in open waters away from the coasts. It is found in all oceans except for the Atlantic.
Sea Countries Animals Lists
Click any of the countries below to see a detailed list of animals located in that country!
When strawberry hermit crabs find shells that are larger than their own, they gather in a line from biggest to smallest. Once the biggest one sheds its shell, the next one in line will claim it, which is repeated down the line.
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Ocean FAQs (Frequently Asked Questions)
What are the most common animals in the oceans?
Some of the most common marine creatures include whale sharks, sharks, catfishes, jellyfishes, sea snakes, sea horses, fish, and sea turtles. However, the world is filled with unexplored territories, so it is possible that many more animals exist that could outnumber the species that researchers have already discovered. Of the animals that researchers know about, approximately 15 animals have gone extinct.