If killer whales surprise scientists and sailors with their attacks, sharks seem to want to do the same by attracting the attention of bathers. The season has started with a thresher or blue shark ( Prionace glauca ) that was seen for a few hours on June 15, in the port of Ciutadella (Menorca). On the 15th of June itself, a tourist was treated for an anxiety attack after seeing a dry cleaner up close on the Aguamarina beach in Oriola (Baix Segura). On the 17th and 18th, a shark of the species known as the thresher fish (Hexanchus griseus) was sighted in the waters off Cape Formentor, in the northernmost part of the island of Mallorca.
The British newspaper The Sun did not miss the opportunity to publish on June 23 a report with the headline "Mystery, sharks swarm in Spanish holiday centers and leave scientists baffled". Curiously, on the same Friday 23rd, the presence of two dry cleaners forced the placing of the red flag and the closure of the beaches of Martinenca, Maricel and Marjal d'Alcanar (Montsià).
"We don't know if there is a common reason or if it's just a coincidence, but it's true that, as has happened in recent days, we've been noticing an increased presence of sharks on the beaches for a few years", explains Manel Gazo, professor and researcher in the department of Evolutionary Biology, Ecology and Environmental Sciences from the University of Barcelona. "They are wild animals and, although they are not aggressive towards humans, you must take all precautions, avoid getting close to them and do not touch them," explains Gazo.
"It is normal that because of the presence of a shark the beach is ordered to be evacuated, it is the protocol that is put into practice, but it should be noted that the species that normally appear on the coast, such as the tintorera or the pike fish, are not not a danger to humans if not provoked; there is no recent case of one of these sharks attacking humans on our coasts", explains Anabel Colmenero, researcher at the Institute of Marine Sciences (ICM)-CSIC and co-founder of Catsharks.
In any case, the presence of sharks is surprising because they generally move in waters relatively far from the coast and because, as recent studies have confirmed, medium-sized or large shark species such as the shark or the sandbar are disappearing of the western Mediterranean, recalls Manel Gazo.
Anabel Colmenero agrees that sharks are in danger of extinction in the Mediterranean and points out that many specimens that approach the beaches show apparent health problems or disorientation. This year the dyer who was seen on June 15 in Aiguamarina was found dead the next day on the nearby beach of La Caleta.
The decline of shark populations in the Mediterranean can be influenced by problems such as rising temperatures and water acidification, pollution, habitat destruction, the presence of boats and noise. But, above all, Colmenero and Gazo agree that the big problem for sharks in the Mediterranean is overfishing. In many cases, indeed, sharks are killed accidentally in trawling or longline fishing operations targeting other fish species. Many of the sharks that are caught, even by accident, end up being traded without any restrictions on this.
"None of the shark species in our waters are protected and there continue to be catches, despite the fact that there are some that appear on the list of endangered species of the International Union for the Conservation of Nature", he laments beehive Certainly, when a shark approaches the beach the alarms go off, but really, more than the bathers, it is the sharks that are in danger.
