'Unusually high' number of turtle strandings in the UK and Ireland

Turtle strandings around Britain and Ireland appear to be on the rise this winter.

While these strandings are thought to be the result of an unseasonably stormy year, climate change could make them more common in future.

Cold and far from home, turtles are increasingly becoming stranded in the British Isles.

Marine Environmental Monitoring, a charity which records turtle strandings, has recorded more strandings in the months since November 2022 than are usually seen in an entire year.

At the time of writing, 16 marine turtles have been washed up on beaches of the U.K. and Ireland, including 15 loggerhead turtles and one Critically Endangered Kemp's Ridley turtle. Of these, only four loggerheads survived being stranded.

Though the causes aren't entirely clear, it's believed that stormy weather and strong currents are responsible for bringing the turtles into colder waters.

Rod Penrose, who leads Marine Environmental Monitoring, says, "Although we see the most hard-shell turtle strandings and sightings between December and February, this year we've had more than usual."

"They're mostly juvenile or injured adults, so it's thought that they struggled to fight the strong winds and currents of severe storms in their native waters of the U.S. and Caribbean."

"These would have carried them offshore into currents crossing the Atlantic before ending up in the U.K.'s cold waters."

Turtles in the UK

There are seven species of marine turtle, of which six have been seen around the U.K. and Ireland. Only the flatback turtle, which is normally found in Oceania, has never been seen in the British Isles.

The turtle that is most common in British waters is the leatherback, which is the largest living species and the only one with a non-bony shell. They are often seen in summer and autumn as they migrate to cold waters in search of jellyfish to eat.

Leatherbacks are able to tolerate cold waters because they are able to control their heat loss. They swim faster in colder waters to keep warm and reduce blood flow to exposed areas to maintain their temperature.

Other turtles aren't able to do this, meaning they aren't well suited to visiting the British Isles. Rarely seen species such as Kemp's Ridley or Hawksbill turtles are usually found after becoming lost during their first migration, or getting drawn off course by currents and the weather.

When these turtles enter waters below 10°C they become "cold-stunned," which causes them to become lethargic and move increasingly less. They eventually lose the ability to swim, leaving them adrift until they wash up on a beach.

Without help, these turtles can suffer from hypothermia, starvation and illness, all of which can lead to death.

What should I do if I find a turtle?

The Turtle Code sets out what to do when a turtle is spotted, and recommends that all sightings of these animals should be reported, whether they are on land or at sea.

Amy Pilsbury, from the Marine Conservation Society, says, "It's important that we gather data on turtle sightings and strandings to build a picture of our seas. This vital information about our ocean's inhabitants, and any changes in their frequency and whereabouts, contributes to scientific research which helps us to find solutions to protect our seas."

The code also contains advice on how to help stranded turtles. Uninjured leatherback turtles should be carefully dragged back into the sea by the shell, taking care to avoid any rocks.

Other species will probably be cold-stunned, and it is recommended that they should be wrapped in a towel soaked in seawater, making sure to keep the nostrils clear.

The animal should be taken to somewhere sheltered and placed on its belly, with its back end raised slightly to help drain any water from its lungs. They should then be reported to groups such as the RSPCA or the BDMLR, who will hopefully be able to help the turtle further.

If the turtle has passed away, its location should still be reported. Anyone moving or handling a dead turtle should wear gloves to reduce the chance of any health risks.

Will turtles become more common around Britain?

Aside from the leatherback, it's very unlikely that marine turtles will ever become regular visitors to the U.K. and Ireland. To prevent them from becoming cold-stunned, sea temperatures would have to be significantly higher than they are now.

That said, the British Isles may see increasing numbers of lost and stranded turtles in the future. Storms are expected to become more intense as a result of climate change, which could see more turtles being driven into waters around the archipelago.

"If storms do increase due to climate change, I would expect to see more hard-shelled turtles, particularly juveniles or compromised adults, around the U.K.," Rod says.

Climate change is also affecting the range of European turtles, which could bring them closer to the U.K.

Rising temperatures are changing the distribution of species such as the loggerhead, which nests in the Mediterranean. Over the past 60 years, their nests have been moving westward as the eastern Mediterranean has warmed, bringing them closer to the Atlantic Ocean.

Their nests are also moving northwards as the turtles move to cooler areas, with a recent paper revealing that two nests found on the shore of the Adriatic Sea in Italy are the most northerly ever recorded.

The same research revealed that eggs in one of the nests was infected with a fungal disease known as Fusarium, which is fatal in around 55% of cases. This parasite is predicted to become more common as climate change makes conditions more suitable for it to spread, potentially increasing turtle deaths.

However, Dr. Cinzia Centelleghe, who co-authored the research, says that there's still some way to go to understand exactly how and why the range of turtles are changing.

"The nesting episodes described in this work, together with a few more in the past years, are opening a big question on the sea turtle nesting expansion in the Mediterranean Sea," Cinzia says. "Climate change, as well as other environmental and anthropic factors, may play a role but further long-term research is needed."

This story is republished courtesy of Natural History Museum. Read the original story here