My Deep-sea Fishery

"You didn't hear it because your ears are bad." Chen Qingsheng who was on the side replied.

Fang Youqun didn'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 loudest animal in the world.

When communicating with partners, blue whales emit a low-frequency, deafening sound that can sometimes exceed 180 decibels, louder than standing on a runway and listening to a jet take off.

Scientists once used a sensitive instrument to detect the sound of blue whales 80 kilometers away, and estimated that the sound of blue whales can 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 air is still about 120 decibels.

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

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

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

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

In the past, in many KTVs and bars, there was a kind of infrasonic subwoofer. The sound produced by this sound wave cannot be heard by humans, but it can make people extremely excited.

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

The dizziness that Xiang Yang suddenly felt just now must have been the blue whale's cry. Although Xiang Yang didn't hear the huge sound wave, it shocked Xiang Yang's nerves.

"It turned out that this guy was screaming. No wonder I felt inexplicably uncomfortable just now." Fang Youqun yelled loudly after understanding the situation.

Then, Fang Youqun asked Xiang Yang again: "Brother Yang, do you know why that blue whale is called? Is it scaring these humpback whales?"

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

Not to mention that 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 similar and individual recognition, and the third is the transmission of environmental information such as foraging, warning and courtship.

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

In the 1960s, some scientists thought it would be a really cool idea to put a lot of radios in the world's oceans to record the singing of blue whales.

Decades later, some scientists who have studied the singing of blue whales for decades made a strange discovery. The singing of every blue whale in the world becomes deeper and deeper every year, but for the reason, They don't know.

This is a very strange phenomenon. Taking humans as an example, despite the differences in language or location, the annual change in the speaking speed of every person living on the earth is very small. The decrease is less than one hertz, and the whole trend is relatively stable and persistent.

Biologists have tried to analyze changes in the blue whale's voice from global warming to rising noise pollution.

Some people think that many factors may cause this phenomenon.

But Xiang Yang thinks that the impact of global warming on the ocean cannot explain the change of the voice of the whale, because the change of the voice of the blue whale is not a single individual, but the entire population, and the impact of the environment is mainly reflected in the change of seawater acidity and density On the other hand, the sound made by the blue whale will not change greatly.

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 waiter's attention.

"I really envy this blue whale. It is free and at the top of the food chain in the entire ocean, and it doesn't need to worry about food." Xu Fang lit a cigarette for himself, and said enviously. said with emotion.

In the entire ocean, almost only killer whales can kill blue whales.

Xiang Yang smiled, but didn't speak.

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

Stranding of blue whales is rare. Due to its special group structure, Xiang Yang has never heard of a group of blue whales being stranded.

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 the Isle of Lewis in the Outer Hebrides of Scotland. It was shot in the head by a whaler, but the harpoon did not explode.

Like other animals, an injured blue whale instinctively holds on to its breath at all costs, and stranding keeps it from drowning.

While blue whales are not easy to kill and preserve, their enormous size, weight, swimming speed and power mean they are not usually a target for whalers.

But when some countries with whaling as the mainstay of their economy hunted sperm whales and right whales in large numbers, when the number of these two whales decreased, whalers had to focus on blue whales.

The earliest hunting of blue whales began in 1864.

In 1864, the Norwegian Svend Foin equipped his ship with a harpoon specially designed to catch large whales.

Although initially cumbersome, the method quickly became popular, and by the end of the 19th century, blue whale populations in the North Atlantic began to decline dramatically.

Since the first blue whale was hunted and killed by humans, the fate of the blue whale is actually doomed.

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

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

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

Whalers use whaling ships to kill blue whales and then upgrade them to huge processing motherships for processing.

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

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

In 1946, the United Nations first introduced quotas on the international whale trade.

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

Rare species can be hunted to the same extent as more numerous species. Due to human hunting and pollution of the marine environment, in 1960, the International Whaling Commission began to ban 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 fewer than 50 blue whales in the world.