People often see mammals in the forests, in the wild and also in zoos. But have you ever wonder about mammals that live under the sea? Some of the key characteristics of mammals are that they are able to give birth below water without having to lay eggs.
Besides the previous ability, mammals also have mammary glands. These glands are used to feed their baby at a young age. The glands would secrete milk for the babies’ nutrition.
Another key factor to consider is how mammals have hair around their body. This also applies to aquatic mammals, most of them have hair around the snout or on top of the mouth.
Some even have them around their body, it is true that you might not be able to identify the fur or hair of these mammals. It is because they have lost their hair during the process of birth.
Most mammals that live on the deeper layer in the ocean zone will less likely have hair on their body because it is not needed for them to survive. For further information about these aquatic mammals let’s get down below.
- Whale
They are the giants of the sea, and they are deep-sea creatures that can withstand high amounts of water pressure. They often come out from the water to get oxygen and then dive deep back down.
There are some attributes that differentiate a whale from any other fishes. For example, the tails of an ordinary fish will move side to side, left to right. While for marine mammals, the tail will move up and down and the shape of the tail is horizontal.
- Seal
Friendly, adorable and intelligent. What more can an aquatic mammal ask for? A seal is social aquatic mammals that range in size such as 10 kilos, to over 100 kilograms.
They are web-footed animals and can withstand extremely cold temperatures. A seal can survive in harsh coldness due to the thick layer of fat surrounding their body.
This thick layer of fat will insulate any cold temperature from snow, ice, and water. Hence, allowing the seal to travel in the snow using their bellies and keeping it warm.
- Walrus
Not all animals here spend their time underwater. The walrus spends a large portion of its time on land too to get fresh air. They are long-living animals and have a lifespan of around 40 years.
This semi-aquatic mammal could only spend 30 minutes being underwater to hunt for food. After hunting for food, it will rise back up to the water surface and finish its meal.
- Dugong
The next aquatic mammal on the list is a dugong. It grows up to 3 meters long and can weigh up to 500 kilograms. This animal consumes a lot of food, but it could only last underwater for several minutes.
That is why it spends most of its day living above water and also looking for water grasses. These dugongs are hairless and have an amazing life span of 70 years.
- Hippopotamus
More gigantic sized animal in line, the hippopotamus is a semi-aquatic mammal. It spends most of its time underwater and can last up to 16 hours submerged in water.
This aquatic mammal is tall in size, that is why most of its body could stay underwater, and its nose could still breathe air. Defeating most of the animals on this list, the hippopotamus could weigh up to 4 tons. That’s the weight of almost two cars!
- Beaver
They can build, they are social, and they are semi-aquatic animals. No wonder they are the national animal of Canada. Beavers are smart animals and can survive in various environments.
They can mostly be found near river banks and would build beaver dams across the river. Although they are social, these animals are monogamous and will only stay loyal to one partner. They reproduce by giving birth and they have fur all over the body.
- River and Sea otter
These semi marine animals have plenty of fur covering its body to protect it from its cold environment. To prevent hypothermia and keep the body warm, the mammalian fur along is a characteristic of a normal otter.
Besides that, otters are great hunters and will dive deep down in silence. They would bite their prey and bring it to the surface of the water. One main reason that the otter brings its food above water, is so that they could avoid predators such as the killer whales.
- Sealion
You may have seen a sea lion from circuses before. But what makes them so special? Well, they are intelligent animals that are quick to learn.
They interact well with humans, that is why you see them doing tricks so easily in circuses. Besides their intellectual skills, sea lions have excellent senses of hearing, sight, and smell.
To learn more about marine mammals, here is an article about the danger of deadly viruses that will infect marine mammals.