Turtle power: Rehabilitated loggerheads released back into the sea

The animals, named Dink and James by their rescuers at the Blue Reef Aquarium in Cornwall, are the only survivors of a record 23 found on the English and Irish coast this year.

They were flown to Gran Canaria and microchipped before being released into the sea at Las Palmas.

Jame Bond, a loggerhead turtle, with Blue Reef employee Matt Slater who nursed the turtle back to health after it was stranded on a beach in Cornwall

Blue Reef curator Matt Slater said: 'They were both in a poor state when they arrived. It was touch and go for a while.'

Loggerheads, which can live for more than 50 years, travel the Atlantic currents in a loop from the U.S. to the Canary Islands. It is thought that bad weather put so many off course this year.

They flew to Las Palmas on Monday June 23 and were released on a beach two days later with their keepers watching on.

If they are spotted again by fishermen or on the beach the tag in their flipper can be used for identification.

Releasing the pair, Blue Reef curator Matt Slater told them: "Hopefully, we won't be seeing you again. Have many, many years of swimming in the ocean."

He added: "It was absolutely beautiful. Let's hope no more turtles get stranded, but if they do we know we can look after them.

"I hope they will be OK. In their lifetime, things will change a lot. The future for turtles in general is not great."

Pascual Calabuig (corr), the centre's director, said: "Seventy-five percent of the sea turtles that we receive have been hurt because of man's activities.

"We see turtles damaged by hooks, nets, pollution, oil and plastic bags. Turtles damaged by boats are the worst to recover.

"We try to patch up their shells with fibreglass, but survival rates are low."

Onlookers, filmed by a cameraman, encourage one of the loggerhead turtles back into the sea

Loggerheads turtles - real name carettta caretta - are categorised as endangered and are threatened by industrial fisheries, habitat loss and climate change.

James was stranded on Blackrock Beach, Bude, on January 26, and Dink a week later further up the coast at Putsborough Beach, Woolacombe, Devon.

Mr Slater said: "They were both in a poor state when they arrived. James was particularly bad. It was touch and go for a while.

"Being a larger, more powerful turtle, James is thought to have battled the strong currents, which left him exhausted.

"Dink, being younger, probably endured less stress as he just drifted on the current and arrived inland faster."  James was suffering from pneumonia, dehydration and a lung infection when he arrived and both turtles had hypothermia.

They were warmed up slowly and the water temperature of their rehabilitation tanks was increased from 10C to 25C.

Mr Slater said: "James was put on a course of antibiotics and anti-fungals to cure infection. When he first took food by himself, after two weeks of tube feeding, we knew he was on the road to recovery."

Loggerheads breed on the beaches of the Mediterranean, West Africa, Brazil and the south-east coasts of the US and Florida has the largest population.

They travel around the large ocean currents in a wide loop and from nesting beaches in Florida, follow the Gulf Stream across the Atlantic to Madeira, and then head south to the Canary Islands and Cape Verde Isles, before heading back to the south-east coast of the US.

Peter Richardson, of the Marine Conservation Society, said: "We are not 100 per cent sure how turtles navigate this route.

"They have some geo-magnetic understanding, for broad-scale navigation, and can use chemical cues coming off of islands, such as windblown dust, as a homing device."  Scientists are uncertain why loggerhead turtles have been stranding on UK and Irish coasts in record numbers this year but experts say extreme weather systems may be a cause.

Mr Richardson added: "From December to February we had strong and persistent south-westerly winds towards UK shores. Small or compromised turtles in the north-east Atlantic may have drifted off-course because of this.

"Juvenile jellyfish are opportunistic feeders. The jellyfish may have attracted them off their normal course. Then they may have got caught in a weather system and blown over. At 15C (59F) the turtles stop feeding and at 10C (50F) they shut down."