There are only about 30 individuals of this species on the planet.
For the first time in history, specialists from the National Oceanic and Atmospheric Administration of the United States recorded the singing of a male Japanese whale - one of the rarest on the planet. They write about this in an article published in the Journal of the Acoustical Society of America.
Today, the existence of many species of whales is threatened by human activities. Females of the northern right whale spend months, and sometimes even years, trying to free themselves from fishing nets, so they have practically no energy left for mating and feeding the calves. This year, off the coast of Sardinia, they found a dead female sperm whale with a dead embryo inside. More than 20 kilograms of plastic waste was found in her stomach.
Japanese whales (Eubalaena japonica) belong to the smooth whale family. According to zoologists, there are about 30 individuals of this species left on Earth. This is one of the reasons why no one has ever recorded their singing. However, the staff of the US National Oceanic and Atmospheric Administration (NOAA) succeeded.
The singing was first captured during the 2010 expedition. Then its participants could not determine the nature of unfamiliar sounds. According to lead author Jessica Crance, the researchers speculated that it could be a Japanese whale, but they have not received any confirmation of this. Analysis of the recording revealed repetitive sound patterns. For the next seven years, they hunted for these sounds, but to no avail. In 2017, scientists were lucky. Four acoustic recorders installed on the buoys recorded a similar song at once. Thanks to them, scientists triangulated the position of the source. This time, they not only recorded the song, but also photographed the person who published it. The images confirmed that the performer was a Japanese whale.
Japanese whale singing / © Associated Press
The researchers' library now contains four different songs that were recorded at five locations in the Bering Sea. The authors have determined that Japanese whales emit a variety of sounds, including “gunshots,” moans, screams, and trills. However, the signals themselves are always a stereotypically repeating sequence of sounds. Jessica Crans believes that in terms of time and number of sounds, they are similar to the songs of the Atlantic walrus (Odobenus rosmarus rosmarus).
Last year, paleontologists at the University of Otago in New Zealand, based on careful analysis of a 34-million-year-old whale skull, concluded that the early whales did not have a whalebone: on the contrary, their mouths were armed with well-developed teeth.