An unusual number of manta rays have been found stranded on Mediterranean beaches in Spain this spring, raising alarm among marine conservationists. At least 20 specimens of the Mobula mobular, also known as the giant devil ray, have appeared dead or dying on beaches in Cataluña, Valencia, Illes Balears, and Andalucía, a worrying figure for a species already listed as endangered by the International Union for Conservation of Nature (IUCN).

These mass strandings are not common, and experts say the pattern suggests something in the marine ecosystem may be going seriously wrong.

---

Not Just a Seasonal Sight

While the presence of rays and even sharks in the Mediterranean during warmer months isn’t unusual, the number of Mobula mobular found stranded along the coast this spring is out of the ordinary. These animals usually stay in deep, open waters and are rarely seen so close to the shore, much less washed up on beaches.

Some of the rays found were up to four metres long, including the tail, and weighed as much as 300 kilos. Most were found disoriented, injured or already dead by the time they were discovered by beachgoers or marine rescue teams.

Scientists Still Searching for the Cause

Marine biologists say the strandings don’t follow any clear pattern. There’s no single explanation for why so many rays are ending up on the sand, but researchers are urgently working to find out. A group of experts from across the Spanish Mediterranean has been formed to investigate the possible causes.

Among the theories being explored are underwater noise pollution from shipping and offshore activities, changes in sea temperature linked to climate change, disruptions in ocean currents, chemical pollution, habitat degradation, and even stress related to breeding. However, none of these possibilities have yet been confirmed.

Experts say that while the species is occasionally seen in the Mediterranean, its presence so close to shore and in such distress is deeply troubling.

Rescue Teams Working Around the Clock

Marine rescue centres such as the Centre de Recuperació d’Animals Marins (CRAM) in Cataluña have been responding to calls almost daily in recent weeks. In some cases, they’ve been able to rescue and release weakened rays back into deeper waters. In many others, the animals have died before help arrived.

These rays are peaceful creatures, harmless to humans, and rely on constant movement to filter oxygen through their gills. Once stranded, they simply cannot breathe and often die within hours.

Public Asked to Stay Alert and Report Sightings

Authorities are urging members of the public to call emergency services on 112 if they see a manta ray close to shore. People should not try to push the animals back into the water or touch them, as this can cause more stress or injury.

Instead, staying nearby, keeping the animal calm, and waiting for trained rescue teams to arrive is the best way to help.

Marine biologists are also encouraging people to share sightings, photos, or video recordings of manta rays in the wild. Every bit of data helps build a clearer picture of what’s happening and what might be causing this crisis.

A Bigger Problem in the Mediterranean?

The rise in strandings is being seen as a symptom of a much wider problem. The Mediterranean Sea is one of the most biologically rich areas in the world, but also one of the most pressured. Heavy maritime traffic, overfishing, coastal development, pollution, and the effects of climate change are all taking a toll on marine life.

Experts say that while the creation of a task force to study the strandings is an important step, it’s not enough. There’s currently no national emergency protocol in Spain for dealing with mass strandings of large marine species, and public awareness remains low.

Organisations like CRAM, which have rescued more than 800 turtles and 350 dolphins over the past 25 years, are doing vital work, but they are underfunded and overstretched.

A Call for Urgent Action

For many marine scientists, the sudden appearance of so many manta rays on Spanish beaches should be seen as a wake-up call.

These rays are symbols of the delicate balance that still exists in the sea. When they begin turning up dead in large numbers, it signals that the balance is shifting. If urgent action isn’t taken, not just to study the problem but to protect the waters they call home, these magnificent animals may disappear from the Mediterranean for good.

Main image: Shutterstock/RugliG