In-Depth Beluga Guide: Behavior, Habitat, and Facts ＠ Doubutsu Kanzen Daihyakka (AnimalBook.jp)

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出典：https://pixabay.com/images/id-4830574/

Belugas are cute with their pure white bodies and chubby shapes!
There are only a few places in Japan where you can see belugas, but you can’t help wanting to take pictures of their adorable gestures, right? But there must be some people who don’t know much about their ecology…
Whether you have seen belugas before or not, why don’t you join me in discovering their secrets?

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～ Basic information. ～

Cetartiodactyla-Odontoceti-Monodontidae-Beluga genus.

They mainly live in the Arctic Ocean, the northern part of the Bering Sea, the Sea of Okhotsk, and so on.

Length : male 3.5-5.5m female : 3-4.1m.

Weight : male 1,100-1,600kg female : 700-1,200kg.

They are also called belugas. As the name suggests, belugas are different from other dolphins in that their whole body is pure white, which is characteristic. They are not dolphins that have lost their color and fallen off, but animals that are independent as a breed.

Interestingly, belugas have no dorsal fin. There are a lot of ice floes floating in the Arctic Ocean where they live, so it is said that having a dorsal fin would get in the way and hit the ice floes when swimming.

And unlike other dolphins, they can turn their heads left and right, which is also characteristic. This is because their neck bones are not stuck together.

出典：https://commons.wikimedia.org/wiki/File:Delphinapterus_leucas_in_shallows.jpg

Belugas also have a part of their head filled with fat called a ‘melon’.

Melons are not only found in belugas but also in other dolphins, but especially the melons of belugas are large, soft and elastic.

Dolphins use a method called ‘echolocation’ to communicate with each other using their melons, but the melons of belugas are so developed that they can adjust the ultrasound more finely than other dolphins.

In addition, the subcutaneous fat of belugas is thick, and while bottlenose dolphins have only 20-30% subcutaneous fat, belugas have 40-50%.

This is said to be to withstand the cold sea. By the way, when food is scarce, this subcutaneous fat can also serve as a substitute for nutrition.

Belugas are social animals, so they usually live in groups of small pods, but during the breeding season from April to August, they sometimes form pods of more than 100 individuals and act together.

The gestation period is about 14-16 months, which is slightly longer than the human gestation period of about 10 months.

The breeding season that started in spring will give birth near the mouth of the river around the summer of the following year. And the lifespan of belugas is about 35-50 years.

出典：https://unsplash.com/photos/djtZXyJkTU

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Beluga’s Q&A.

Where does the beluga whale get its name?

They are called ‘Beluga’ in English, but actually they are called ‘shiroiruka’ in Japanese. This time, we will introduce why they are called shiroiruka in Japanese and the origin of the name.

The name shiroiruka comes from a very easy-to-understand meaning that they are dolphins with white bodies. By the way, shiroiruka is the Japanese name, and the alternative name ‘beluga’ is the name in Russian. In Russian, ‘white’ means ‘belyi’, so it was named from there.

出典：https://commons.wikimedia.org/wiki/File:Delphinapterus_leucas_head_3.jpg

Why do beluga whales live there?

The habitat of belugas is the Arctic Ocean, where there are many places with floating ice. The ice sometimes hides the belugas, so they have the advantage of being hard to find by enemies.

In other words, belugas live in the Arctic Ocean to protect themselves from enemies.

By the way, did they move and live in the Arctic Ocean because their bodies are white? Or did their bodies become white because they live in the Arctic Ocean? The latter is considered to be more likely as the answer.

In the past, various animals lived in the Arctic Ocean, but some of them were eliminated by enemies and are now extinct.

To survive in such a situation, it is thought that the bodies of belugas adapted to the environment and became white.

出典：https://commons.wikimedia.org/wiki/File:Belugas_(124233821).jpeg

What do beluga whales eat?

Like bottlenose dolphins, they eat fish and other seafood such as crabs and other crustaceans.

出典：https://pixabay.com/images/id-1190393/

How are beluga baby whales not white?

Actually, baby dolphins are not white from birth, but gray at first.

There is a reason for this, and as we introduced in the basic information, belugas give birth near the mouth of a river or in shallow places. In places where there is little ice, the white body of belugas stands out very much.

Even if they are adult dolphins, there is a risk that baby dolphins that have just been born will be targeted by polar bears if they are found, but if they have gray bodies, they can blend in well with the gravel around them.

The reason why baby belugas are gray was a wisdom to survive.

出典：https://commons.wikimedia.org/wiki/File:Aurora_and_baby_2_-_vancouver_aquarium.jpg

Is it true that beluga whales molt are life-threatening?

As we introduced earlier, baby belugas are gray at first. And as they grow bigger, they gradually change to white over a long period of time, shedding their skin little by little.

Even as adults, they continue to shed their skin, repeating it once a year. But why is beluga shedding a matter of life and death?

It has to do with the way they shed their skin. Belugas live in the sea with a lot of ice, so they sometimes bump into the ice while swimming.

Then their skin becomes gradually ragged, so they shed their skin to replace the damaged skin, but instead of peeling off all at once, they rub their body against the gravel on the seabed and drop off the old skin little by little.

The place where they shed their skin is relatively shallow in the sea, but if they get too absorbed in rubbing their body, the waves will completely recede and they will be left behind on land and unable to return to the sea.

Not being able to return to the sea means death, so that’s why shedding is a matter of life and death.

出典：https://pixabay.com/images/id-170101/

What is beluga whale bubble ring?

Have you ever seen belugas spitting out something ring-shaped at the aquarium?

This is called a bubble ring, and not only belugas, but other types of dolphins can also make bubble rings.

Bubble rings are phenomena where the air that is spit out from the mouth becomes bubbles and rotates while rising in a donut-like shape, but actually we humans can also make them.

However, in the case of belugas, it is not clear how they make them and what their purpose is.

Are they simply making rings and having fun with their friends, or are they using them as one of the fishing methods to catch fish and other things…

But it is famous that seeing bubble rings at the aquarium makes you feel happy, so if you have a chance to go out, please observe them.

出典：https://commons.wikimedia.org/wiki/File:Delphinapterus_leucas_Bubble_Ring.JPG

Is it true that beluga whales were Russian spies?

The story began when fishermen in the Norwegian Arctic Ocean found a beluga whale wearing a harness.

The fishermen were curious and approached the beluga whale, which did not seem to be afraid of humans and came close to the boat. But when they looked closely, they saw that the harness also had a small camera attached to it, and when they checked it, they found out that it was made in Russia.

They did not understand the situation well, but they felt sorry for the beluga whale because the harness looked very tight and uncomfortable on its body, so they decided to take it off for now.

When a marine biologist examined the harness in detail, he found out that “there are different types of harnesses, and the one that was attached to this beluga whale was different from the type used for marine research.”

By the way, Russia is famous for having a military base in this Arctic Ocean. But there is not enough evidence to prove that the beluga whale was really used as a Russian spy.

However, for example, the US military has a record of using dolphins as spy animals, and the Russian military also had a plan to use animals as spy personnel.

This means that there is a possibility that the beluga whale was sent as a spy. The answer from the Russian side is “We admit that we are training dolphins as combat personnel, not spies.” But it is certain that the Russian military owns beluga whales, but how they are actually used is a secret.

出典：https://unsplash.com/photos/kvTQEU3OuzA

Is it true that beluga whales are called sea canaries?

The answer is yes. They got this cute nickname because they make high-pitched sounds and use different calls to communicate with their friends, just like canary birds.