Experts: Lonely, sexually frustrated dolphin is behind attacks on swimmers in Japan

Tokyo:

Some beaches in Japan have extensive security measures in place to look out for fins. But it is not the sharks that authorities and lifeguards are worried about – it is the dolphins. And not the whole herd, just a single, lonely, sexually frustrated dolphin. According to the BBCThis mammal is responsible for a rise in attacks on swimmers in Wakasa Bay, about 300 kilometers from Tokyo. These attacks have injured up to 18 people, including an elementary school child whose finger required 20 stitches.

Attacks have increased in recent years – one in 2022, six last year and 18 so far in 2024.

And local authorities are sure that it is a single dolphin attacking people.

“It is believed that this is the same individual, as the wounds on the tail fin are similar to those of the dolphins spotted off the coast last year. In addition, it is rare for dolphins, which normally move in groups, to be alone for so long,” Tadamichi Morisaka, a cetacean professor at Japan's Mie University, told the Japanese outlet. NHK.

The dorsal fin is like a dolphin's fingerprint, as each fin has distinctive notches, grooves and pigmentation.

Other experts have also expressed their opinions and speculated as to why a single dolphin might be behind all these attacks.

“Bottlenose dolphins are very social animals and this sociality can be expressed in very physical ways. Just like with humans and other social animals, hormonal fluctuations, sexual frustration or the desire to dominate can lead the dolphin to injure the people it interacts with. Because they are such powerful animals, this can cause serious injury to humans,” said Dr. Simon Allen, a biologist and lead researcher on the Shark Bay Dolphin Research project, who BBC.

The biologist suspected that the dolphin might have been expelled from its own community and was looking for company.

“In my experience, it is usually more of a defensive behavior when people get too close to these dolphins and don't know how to behave,” says Dr. Matthias Hoffmann-Kuhnt, a marine mammal expert at the National University of Singapore.

The dolphins are considered very friendly towards humans, but their attacks can be fatal. One well-known incident occurred in Brazil, where a dolphin nicknamed Tiao injured 22 people in 1994.

In the coastal town of Mihama, authorities have put up signs warning the population that the mammals can not only “bite you with their sharp teeth and cause you to bleed,” but can also “drag you into the sea, which can be life-threatening.”