Seals are mammals! They have everything that makes an animal a mammal. They are warm-blooded, vertebrates, they have fur, and, above all, mothers feed their babies with milk expressed through their mammary glands. Indeed, seal milk is one of the richest types of milk. The milk of a hooded seal, for example, is so fat that a mother only needs to breastfeed her baby for two weeks, at most, before he becomes independent.
Seals, also called pinnipeds, are not just mammals, but belong to a special group called marine mammals. These mammals live in or near water for most of their life, especially in the ocean. Pinnipeds spend most of their time in the water hunting for something to eat, but they have to go ashore to give birth, mate and shed their hair. This is one of the features that sets them apart from whales, dolphins and porpoises, which are completely aquatic and are at risk of death if washed ashore.
There are three main types of pinnipeds. These are walruses, real seals that do not have external ears and need to be dragged over land or ice, and sea lions, which have external ears, and they can move on fins. Walruses, by the way, do not have fur all over their bodies, but they have so many sensitive mustaches that they inspired them to create human mustaches. The closest living relatives of seals are bears, and seals separated from them about 60 million years ago.

Why do people think seals are not mammals?
Perhaps people think that pinnipeds are a species of fish, as some think that whales and dolphins are species of fish. This is because they have fins and flippers instead of legs, and they are perfectly adapted to life in the water. But seals are not fish, they are mammals.
Are seals threatened?
One in five species of pinnipeds is endangered due to reckless hunting, climate change and environmental pollution. Some pinnipeds have become entangled in nets designed to catch fish or other marine life. For example, global warming is melting sea ice, making it increasingly difficult for them to find a place to escape. Warm water retains oxygen worse, and this reduces the number of seal prey. Pollution is harmful to marine life in general, and even the noise from ships can be dangerous. Here are some endangered pinnipeds.
- Mediterranean monk seals. In some populations of the Mediterranean, fewer than 700 of these animals live. Because of this, it is one of the rarest pinnipeds in the world.
- Ungava seal. It is a rare freshwater seal native to northern Quebec. Scientists believe that there are fewer than 100 of these animals left.
- Saimaa ringed seal. This animal is another freshwater seal and is only found in Lake Saimaa in Finland. An estimated 400 people remain.
- Hawaiian monk seal. This animal is one of two mammals found in Hawaii. The other is the Hawaiian gray-haired bat.
- New Zealand sea lion. Also called the Wakahao, this large pinniped is one of the rarest sea lions. This is the only species in Phocarctos genus.
- Australian sea lion. This sea lion, which is also the only species of its kind, is known for its strange breeding cycle.
- Galapagos fur seal. This little seal is the smallest of the fur seals. Found only in the Galapagos Islands.
- Galapagos sea lion. This sea lion is found both in the Galapagos Islands and less commonly in Isla de la Plata. This is the smallest sea lion.
- Walrus. This charismatic pinniped is renowned for its tusks and sheer size. A large male can weigh over two tons. Its guard status is vulnerable.

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FAQ (Frequently Asked Questions)
Why is printing good?
Seal hunting has been carried out since ancient times. They were hunted and in some cases are still hunted for their fur, especially their puppies. They are also hunted for their meat and fat. More and more pinnipeds are being protected by laws that prohibit them from reckless hunting or hunting.
How many species of seals are there?
According to the IUCN, there are 36 species of pinnipeds. Some of these species have subspecies.
Where are the fillings found?
Seals are found mainly in the polar regions, although there are a few such as monk seals that are found in warmer waters such as the Mediterranean. But even if the water is warm, it cools due to seasonal ocean currents. This allows them to become richer in nutrients. The vast majority of pinnipeds are found in salt water, and only a few of them are found in fresh water. These include the Ungava, Saimaa ringed seal, Baikal and Caspian seals.
Are they omnivores, herbivores or carnivores?
Pinnipeds are carnivores because they only eat animals such as krill, squid, fish, penguins, and smaller seals, including the young of other species.
Are seals dangerous?
They are not actually dangerous to humans, but some are more aggressive than others, especially during the breeding season or if they are hungry. At least one person has been killed by a leopard seal. Scientists believe the animal mistook the man, who was wearing diving gear, for a seal, which was a common prey for the leopard seal. Looking at the teeth of many pinnipeds, one can see the fangs and predatory teeth of predators, and even if the animal is not going to directly kill a person, it can cause a serious bite. Moreover, seals are surprisingly large animals. Pinnipeds such as the elephant seal and walrus are too large to be associated with.
Do seals migrate?
Some species of pinnipeds do migrate. Indeed, the migration of the northern elephant seal is the longest of all mammals. Males swim 13,000 miles and females 11,200 miles each year in search of food and then come ashore to breed, molt and give birth. Hoods and harp seals were not believed to have migrated, but they could have migrated from their ancestral home in Greenland and northeastern Canada to New England.
Why do seals molt?
Pinnipeds need to shed from time to time because their fur does not keep them warm, but simply protects them from injury and burns from the ultraviolet light of the sun. In addition, they need to shed mostly on land because they need to channel their blood close to the skin’s surface to stimulate the growth of new fur. They could not do this in the cold waters, where most seals live, because the blood would go to their internal organs. Due to the fact that their fur and even skin peeled off, they very quickly became hypothermic. A seal that still visits the water during molting takes much longer to acquire new fur.
Many pinnipeds molt immediately after pregnancy, although elevated levels of pregnancy hormones can interfere with molting. The animal bypasses this through a phenomenon called embryonic diapause. While it is molting, the embryo simply does not develop and the hormones are controlled.
There are animals that not only lose and grow their fur, but also lose and regrow the top layer of their skin. Elephant seals do this, and not only are they forced to stay on land for several weeks, but they are also unable to eat during this time. This is called a catastrophic molt.
How long do seals live?
The lifespan of a seal depends a lot on the species, but like mammals, seals can live a long time. A gray seal can live for over 30 years, a Galapagos sea lion can live 15 to 24 years, a walrus can live 30 to 40 years, and although a male elephant seal can grow almost twice as massive as a walrus, it only lives 11 to 13 years. Puppies of all species are most vulnerable to predators and may even be trampled to death by males of their own species when bulls fight rival males or attempt to mate with the puppy’s mother.