My Deep-sea Fishery

"You didn't hear it because your ears can't work." Chen Qingsheng on the side replied.

Fang Youqun doesn't believe in evil, "Why, you all heard it just now, but I didn't hear it?"

Xiang Yang smiled and said, "No, including me, we didn't hear it just now."

The blue whale is the most vocal animal in the world.

When communicating with a partner, the blue whale will make a low-frequency, deafening sound, which can sometimes exceed 180 decibels, which is louder than the sound made by standing on the runway and listening to a jet plane taking off.

Scientists once used a sensitive instrument to detect the sound of blue whales from 80 kilometers away, and estimated that the sound of blue whales could reach 150 to 185 decibels at the source.

Even considering the different impedances of water and air, and different standard reference pressures, the equivalent sound range in the air is still about 120 decibels.

For comparison, the sound of a pneumatic drill is about 100 decibels.

But humans cannot realize that the blue whale is the loudest animal.

Because the fundamental frequency of the blue whale population is around ten hertz, and the lowest frequency that humans can hear is twenty hertz.

However, the fact that humans cannot hear the calls of blue whales does not mean that humans cannot feel the calls of blue whales.

In the past, in many bars, there was an infrasound subwoofer. The sound emitted by this sound wave could not be heard by humans, but it can make people extremely excited.

However, this type of subwoofer is not allowed to be used now, because the surrounding residents will cause severe insomnia and other effects if they listen to it for a long time.

Just now, Xiang Yang suddenly felt the dizziness. It must be the blue whale who suddenly called. Although Xiang Yang did not hear the huge sound wave, it had an impact on Xiang Yang's nerves.

"It turned out that this guy was yelling. No wonder I felt uncomfortable for a while." Fang Youqun yelled immediately after understanding the situation.

Then Fang Youqun asked Xiang Yang again: "Brother Yang, do you know why the blue whale is called? Are you threatening these humpback whales?"

Xiang Yang shrugged, "I don't know why this blue whale calls."

Not to mention Xiang Yang doesn’t know why blue whales make such extremely sad calls. Even scientists don’t know why blue whales make sounds. In 1995, some scientists put forward several hypotheses. One is that blue whales rely on sound to maintain their individuality. The second is the recognition of the same kind and the individual, and the third is the transmission of environmental information such as foraging, warning and courtship.

In addition, some people have suggested that blue whales make sounds to maintain group contact, such as communication between females and males, or use echoes to locate features and food like bats.

In the 1960s, some scientists thought it would be a very cool thing to put a large number of radios into the world’s oceans to record the singing of blue whales.

Decades later, some scientists who have studied blue whale singing for decades have come to a strange discovery. The singing of every blue whale in the world becomes deeper and deeper every year, but for the reason, They are not clear.

This is a very strange phenomenon. Take humans as an analogy. Despite the differences in language or location, the speaking speed of every person living on the earth changes very little every year, and this slowdown is as small as every year. The reduction is less than one Hz, and the overall trend is relatively stable and continuous.

Biologists have tried to analyze the changes in the sound of blue whales from global warming to increasing noise pollution.

Some people think that many factors may cause this phenomenon.

However, Xiang Yang feels that the impact of global warming on the ocean cannot explain the change in the sound of the whale, because the change in the sound of blue whales is not a single individual, but an entire group, and the environmental impact is mainly reflected in the changes in the acidity and density of the sea. On the above, the sound of the blue whale will not change significantly.

In contrast, noise pollution may be a more convincing explanation.

Xiang Yang once boldly imagined that in a crowded bar, customers can only raise their voices to attract the attention of the waiters.

"I really envy this blue whale. It's free. It's almost at the top of the food chain in the entire ocean. You don't need to worry about food." Xu Fang lit a cigarette for himself, and was quite envious. With emotion.

In the entire ocean, there are almost only dead blue whales that killer whales can kill.

Xiang Yang smiled and did not speak.

In fact, blue whales have another natural enemy besides killer whales, and that is humans.

Blue whale stranding is rare. Because of its special group structure, Xiang Yang has never heard of blue whale stranding.

But blue whales will also be stranded, and most of the time, they are stranded because of humans.

In 1920, a blue whale ran aground on the beach of Lewis Island in the Outer Hebrides, Scotland. It was shot in the head by a whaler, but the harpoon did not explode.

Like other animals, the injured blue whale instinctively insists on breathing at all costs, and stranding can prevent it from drowning.

Although blue whales are not easy to kill and preserve, their huge size, terrifying weight, swimming speed and power mean that they are usually not the target of whalers.

But when some countries that rely on whaling as their economic backbone are killing sperm whales and right whales in large numbers, when the number of these two whales decreases, whalers have to target blue whales.

The earliest killing of blue whales began in 1864.

In 1864, Norwegian Svender Foin assembled his ship with a harpoon specially designed to catch large whales.

Although this kind of harpoon was troublesome at first, this method quickly became popular. At the end of the 19th century, the number of blue whales in the North Atlantic began to decrease.

Since the first blue whale was killed by humans, the fate of the blue whale has actually been doomed.

Because there is a thick layer of fat under the skin of the blue whale, it can be used for soap, shoe polish, etc.

Therefore, blue whales will inevitably be hunted by whalers in large numbers.

Since 1864, the killing of blue whales has increased rapidly around the world. By 1925, the United States, the United Kingdom and Japan have all joined the ranks of killing blue whales.

The whalers use the whaling ship to kill the blue whales and then upgrade the blue whales to a huge processing mother ship for processing. UU Reading www.uukanshu.com

In 1930, only 41 well-known whaling ships on record killed 28,325 blue whales.

At the end of World War II, the blue whale population was close to extinction.

In 1946, the United Nations introduced quota restrictions on international whale trading for the first time.

But these quotas are invalid, because the agreement does not take into account the differences between different species.

Rare species can be hunted to the same extent as larger species. Due to human hunting and pollution of the marine environment, in 1960, the International Whaling Commission banned the killing of blue whales.

But at that time, 350,000 blue whales had been killed, and the population of blue whales in the world had been reduced to less than one percent of what it was a hundred years ago.

By the end of the nineteenth century, there were only less than 50 blue whales living in the world.