Do you know what the largest animal on Earth is? It's the blue whale.

The blue whale, which is about 24 meters long, is also called the "right whale" because of its huge size. It weighs about 160 tons, making it the heaviest animal that exists today, as well as the heaviest animal that has ever existed in history. Despite its massive size, the blue whale feeds on very small krill. Since it is so large, it is said to eat about 3,500 kg of krill a day.

The blue whale is currently listed as endangered (EN) on the IUCN Red List of Threatened Species. It is estimated that there are about 5,000 to 15,000 left in the world.

When looking at the reasons for the endangerment of endangered species, illegal hunting is almost always mentioned. In many cases, the population has declined sharply due to indiscriminate hunting. In the case of the blue whale, you might think that it is so large that it would never be hunted, but humans are capable of both good and bad things. In the 20th century, as marine transportation developed and hunting techniques evolved, many blue whales were overfished, resulting in their endangerment. In the 1930s, when people were ignorant of animal and environmental protection, 30,000 right whales were caught every year.

As you can see from the habitat map above, the blue whale lives in almost all the oceans. Therefore, international cooperation is essential to conserve the blue whale population. We explained earlier that the blue whale was endangered due to indiscriminate hunting. To prevent this kind of illegal fishing, the International Whaling Commission has stepped up its protection efforts, and the population is fortunately on the rise.

Whaling can be prevented by laws and regulations, but a bigger problem is marine pollution, which is difficult to prevent by human power. Since the blue whale's habitat is the entire ocean, protecting the marine ecosystem is the most important thing for the future conservation of the blue whale population. Currently, an area of about 400,000 square kilometers is being protected to protect marine life, including the blue whale. While this is a vast area, it is only about one-ninth of the entire ocean.

Various whales with enormous bodies also function as carbon sinks. They are natural carbon sinks on a huge scale. The blue whale, the largest whale on Earth, can also absorb a huge amount of carbon, making it very beneficial to the marine ecosystem. Let's hope that the blue whale can continue to protect the marine ecosystem in the future.