World Whale Shark Day | The emotionally stable "cute baby" in the sea, is he a whale or a shark?

Xu Huangang

With its charming appearance, unique "fingerprints" and huge size, but very gentle temperament, this is the "undersea star" - the whale shark. When the sun shines through the sea, the glittering scales on the back of the whale shark and the spots on its back look like a dazzling starry sky.

Such a fascinating species is facing severe threats to its survival. In 2008, the International Whale Shark Symposium held in Mexico designated August 30th of each year as "World Whale Shark Day". August 30th this year is the 17th "World Whale Shark Day". Let's talk about the flowing light in the deep sea.

Is it a whale or a shark? Simply look at its breathing

The name "whale shark" comes from fish biology, indicating that the whale shark is as large as a whale.

Since the word "shark" is in the name of whale shark, many people may wonder: Is whale shark a whale or a shark? In fact, whale sharks belong to the shark family and have nothing to do with whales.

So, how do you tell the difference between a whale shark and a whale?

First, look at the class. Whales belong to the order Cetacea, class Mammalia, phylum Chordata, while whale sharks belong to the order Ocellaris, class Chondrichthyes. Whale sharks only have one family and one genus in the entire shark order, namely the family Cetiidae.

Second, look at the species. Whales are mammals that give birth to live young, and their tail fins swing up and down when they swim; whale sharks are fish that give birth to live young, and their tail fins swing left and right.
Third, look at the animal's attributes. Whales are warm-blooded animals, while whale sharks are cold-blooded animals, so the two are different in terms of body temperature, food requirements, and basal metabolic rate.

Fourth, look at the breathing method and skin surface. Whales breathe through their noses and have smooth skin without scales; whale sharks breathe through gills and have shield scales all over their bodies.

In fact, the main difference between whale sharks, whales and sharks is reflected in the "order" in biological taxonomy. Whale sharks belong to the order Meselachiata, sharks are usually in the order Carcharhinidae, and whales belong to the order Cetacea.

It is a shark, but its temperament is very gentle

Whale sharks are also different from other types of sharks, the most important of which is their temperament. Whale sharks are gentle and never attack or harm humans. They can play with divers and are known as "gentle giants of the sea." Other types of sharks, such as great white sharks, tiger sharks, and bull sharks, are more aggressive and threatening, and are known as "ocean killers."

The ancestors of whale sharks began in the Jurassic and Cretaceous periods, 200 million to 66 million years ago. However, because whale sharks are relatively rare, this species appeared relatively late in human records. According to the History of Zoology, before the mid-1980s, there were less than 350 confirmed reports of whale sharks worldwide.

The whale shark is the largest fish on earth, with a body length of about 20 meters and a weight of about 20 tons, just like a mobile submarine, and is the world's largest fish. In biological taxonomy, the whale shark is unique, being the only member of the family Cetiidae and the genus Cetiidae, and a unique group in the class Chondrichthyes.

"Fingerprint" recognition, a unique "ID card"

Like human fingerprints, the blue-gray back of whale sharks is covered with white or light yellow spots, which seem to be the same. In fact, the spots of each whale shark are unique and can be used to identify different individuals. Therefore, whale shark researchers have set up a whale shark "fingerprint library" to record photos of whale sharks recorded in various places. Scientists use these spots for visual identification and tracking to better understand and protect these gentle marine giants.

Whale sharks like to live in the middle and upper layers of warm oceans. Tropical and temperate seas are their ideal habitats. Their main distribution range is approximately 30°-35° north and south latitudes, and sometimes they migrate between 41° north latitude and 36.5° south latitude. They can be found in the South my country Sea, Taiwan Strait, East China Sea, southern Yellow Sea and other seas.

It is generally believed that the diet of whale sharks mainly includes plankton, krill and small free-swimming animals. However, new research shows that floating large algae Sargassum is also an important food source for whale sharks. Therefore, scientists believe that whale sharks are the largest omnivorous animals in the world today. The relevant research has been published in the journal Biology.

Taking multiple measures to help whale sharks escape endangerment

The number of gentle whale sharks has been drastically reduced due to human activities, overfishing, marine pollution, ship collisions and other factors. In addition, whale sharks grow slowly and have a long reproduction cycle. Once the population declines, it is extremely difficult to recover.

Statistics show that in the past 80 years, the number of whale sharks in the world has dropped by 50%, with only about 7,000 individuals left in the wild. According to the classification of the IUCN Red List of Threatened Species, whale sharks have been listed as "endangered".

Protecting whale sharks is of great significance. First, it has scientific value. By studying whale sharks, scientists can better understand their biological characteristics and marine ecological environment, which is of great significance for protecting whale sharks and the marine ecological environment.

The second is to develop ecotourism. Take Donsol Bay in the Philippines as an example. For more than 30 years, this "capital of whale sharks in the world" has become one of the world's tourist destinations where whale sharks can be seen up close. But before that, local fishermen made a living by killing whale sharks. The subsequent development of the ecotourism industry has increased their income instead of decreasing it. It can be seen that the development of whale shark ecotourism is not only beneficial to the protection of whale sharks, but also can drive the rapid development of the local economy.

The third is cultural significance. In some places, such as Vietnam and Kenya, whale sharks are regarded as the incarnation of gods, as symbols of harmony, auspiciousness and abundance, and they are believed to bring good luck and prosperity. Whale sharks have also become a beloved character in many film, television and literary works.

In recent years, the protection of whale sharks has achieved remarkable results. my country has listed whale sharks as a national second-level key protected wild animal. The Philippines, India and Taiwan have successively banned commercial hunting, trafficking, import and export activities related to whale sharks. At the same time, relevant countries and regions have also helped whale sharks escape from endangerment and "rejuvenate" through a variety of measures such as establishing protected areas, strengthening supervision and publicity and education.