The world's most incredible aquatic mammals - Under the sea, as well in lakes and rivers, there is a fantastic world filled with incredible animals, all with unique and distinct characteristics. The mammals that live in the water are often confused with simple 'fish' but they're much more than that.

Discover more in this gallery and be amazed by the diveristy of these mammals!

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Amazonian manatee -

It is definitely one of the strangest mammals in the world and can be found in the rivers of Peru, Bolivia, Colombia and Ecuador. It is the smallest species of manatee.

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Capybara - These animals are similar in part to hippos. They sit with their eyes and nose above the surface of the water to watch everything that goes on around them. They can be found in river banks of South America, particularly in the Andes.

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Polar bear - Polar bears are also aquatic mammals. Equipped with a thick coat of fur, these animals are very well prepared for the negative temperatures in the water and the air. They're good swimmers and can swim at a speed of 9km/h.

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Ringed seal - This curious species of seal can be found in the Arctic and is thought to be the smallest species of seals in the region.

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American beaver -

This aquatic rodent has transparent eyelids which helps it see underwater, and sharpened teeth to chew wood with.

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Amazon river dolphin -

Also known as the pink river dolphin, this mammal can only be found in the waters of the Amazon and Orinoco rivers.

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Dugong -

This unique species mammal is similar in appearance and behavior to manatees, and can be found in Australia and Africa. Dugongs spend most of lives underwater.

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Eurasian otter - Coming from the fresh waters of Europe, this mammal loves to eat fish, frogs and even some birds.

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North American river otter -

This otter's hair is water resistant, and their bodies are streamlined to allow them swim at fast speeds in rivers, and they can also hold their breath for eight minutes.

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Humpback Whale - These animals emit a beautiful sound that echoes through the ocean. These whales can weigh up to 40 tonnes and measure between 14 and 19 meters. Despite their weight and size, they're excellent swimmers and navigate vast distances every year.

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Orca - One of the best-known mammals in the world is also one of the deadliest predators. You might know it better as the killer whale. They can snap up seals straight from the ice.

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Platypus -

This is a truly unique species. A combination of duck, beaver and otter all in one. Not only that, it's also one of the only species of mammals that lay eggs. Male platypuses are venomous.

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Hippopotamus -

A major mammal found in Sub-Saharan Africa. The name hippopotamus comes from Greek where it was called the 'horse of the river.' They're excellent swimmers, and their bite has an estimated force of 8,100 newtons!

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Indian rhinoceros -

Considered one of the most valued species in the world, these rhinos can be found in the north of India and in Nepal. One of the biggest differences between this animal and its African 'cousin' is that these only have one horn.

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Leopard seal - One of the most dangerous predators in the world. They are hunters without equal and the only seal known to eat warm-blooded prey.

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American water shrew -

This species has hairs on its feet which help it to move in the water. They can be found in the mountains in the north of the United States, Canada and Alaska.

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European water vole -

These mammals are often confused with rats, but this species is found in slow-moving lakes in Europe, Russia and West Asia.

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Moose - Moose are the biggest species of deer in the world and seek refuge in the water. They can even been seen subermerging themselves completely in lakes and waters.

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Common bottlenose dolphin -

This is the most common species of dolphin, the one known and loved by everybody. As well as being extremely intelligent, they locate their prey using echolocation.

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Coypu - This huge rodent comes from South America and feeds mainly off aquatic vegetation and some crustaceans.

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Walrus -

The walrus is a very social mammal with long whiskers that make it look like they have hilarious moustaches. They live in the Arctic Ocean and though they spend a lot of time on land, this species can dive up to depths of 48 meters.

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Cuvier's beaked whale - This whale can be found in all of the world's oceans, and when they hunt they can dive to depths of 2,000 meters.

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Water opossum - This species is found in the rivers and lakes of southern Mexico and Argentina. It is the only species of which both the males and females have pouches. The average life expectancy for this animal is three years.

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Vaquita - This rare kind of porpoise is on the brink of extinction. They can somtimes be seen in the Gulf of California, in Mexico.

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Harp seal - This seal can be found in the Arctic and Atlantic Ocean. They stay submerged for around 15 minutes and they love to hunt fish and crustaceans.

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