Dolphins Are Beaching Themselves in Japan And No One Knows Why

Experts are mystified by a series of dolphin beachings that has killed several of the mammals and appears to have injured or weakened many others. About 40 melon-headed whale dolphins washed up on shores east of Tokyo over the last few days, and that’s just the most recent incident.

This school of dolphins did get lucky, though, thanks to quick-thinking surfers. The volunteers banded together to guide the animals back into the surf. While they worked for hours to get the dolphins to safety, even those who were rescued seemed to be struggling to breathe. Two died, even while volunteers tried to save them, reported Vice World News. Seven dolphins were reported dead in total: three on Monday and four more on Tuesday.

“They may have been weakened from swimming too close to the coast where the water is cold,” said Yukio Miyauchi, head of the Choshi Ocean Institute, according to the news outlet. Melon-headed whale dolphins usually live in warm, tropical waters, but they often chase schools of fish north in spring.

What exactly caused the mass stranding is unclear. The National Museum of Nature and Science will conduct tests on the dolphins that died to try to understand what’s going on, the Japan Times reported.

This, sadly, isn’t the only mass beaching to happen this year. At least 910 dolphins have washed up on France’s Atlantic coast over the last few months, an increase from previous years. The country has levied strict fishing restrictions in response, hoping to protect the marine mammals. 

At least eight dolphins died on the coast of New Jersey in late March, and more than a dozen dead whales have been found on the U.S. East Coast this year alone. Scientists in New England theorize that the American whale deaths could be due to sonar being to map the ocean floor. Others suspect a local wind energy project, though there’s less evidence for that line of thinking. 

Researchers are currently investigating the deaths of Japan’s dolphins, but strong theories have yet to emerge.