A cold-stranded turtle that was originally rescued by two dogs has now been released back into the wild.

The loggerhead turtle, named Tonni, was discovered in January 2023 on Moel-Y-Don beach, a quarter of a mile from Anglesey Sea Zoo and on the shore of the Menai Strait, by dogs Winnie and Kerry.

The dogs, along with their owner, protected the turtle from seagulls and alerted Anglesey Sea Zoo, whose staff staged a rescue and transferred Tonni to specialist intensive care.

The turtle, measuring 25 centimetres in length and 1 kilogram in weight when found, was in a critical condition - comatose, dehydrated, and malnourished.

It was given the unisex name Tonni, derived from the Welsh tonnau meaning 'to have,' because it was originally too diminutive for its sex to be determined.

The team at Anglesey Sea Zoo provided round-the-clock care for the first one or two weeks, and then maintained Tonni at a temperature of 21 to 22 degrees Celsius.

Tonni was discovered cold-stranded by two dogsTonni was discovered cold-stranded by two dogs (Image: Anglesey Sea Zoo)

Tonni was then moved to a larger tank with ample swimming space.

After 20 months of care, the turtle was ready for release, weighing a healthy 8.5 kilograms (more than eight times its found weight).

Anglesey Sea Zoo's curator, Matt, along with director Frankie, drove Tonni to Plymouth to deliver the turtle to the Royal Navy.

Tonni was taken on board the departing HMS Medway for release a few days later into the Atlantic Ocean, near the Azores.

After 20 months in the care of Anglesey Sea Zoo, Tonni was delivered over to the Royal Navy which brought the turtle aboard HMS Medway for later release near the AzoresAfter 20 months in the care of Anglesey Sea Zoo, Tonni was delivered over to the Royal Navy, which brought the turtle aboard HMS Medway for later release near the Azores (Image: Royal Navy)

Frankie Hobro, director and owner of Anglesey Sea Zoo, said: "We are delighted that Tonni will be living their best life now as a free turtle back in the Atlantic Ocean where they belong!

"Huge thanks to everyone who made this possible with your donations and support!

"We will of course miss seeing Tonni here every day after 20 months of care."

Anglesey Sea Zoo is currently caring for another turtle, named Rhossi.

Rhossi is a rare Kemp's ridley turtle, and will eventually need to be repatriated to the Gulf of Mexico - the only place in the world where the remaining few thousand of the species "still has a stronghold," according to Anglesey Sea Zoo.

The zoo is fundraising for what it describes as the UK's first dedicated turtle rescue facility.

According to the zoo, turtle strandings in the UK are becoming more common, due to rising sea temperatures and an increase in violent Atlantic storms in autumn and winter.

Donations to the new facility can be made at https://www.gofundme.com/f/anglesey-sea-zoo-turtle-rescue-facility

Anglesey Sea Zoo encouraged the public to report any stranded turtles they encounter to Marine Environmental Monitoring on 0800 6520 333, or the Anglesey Sea Zoo directly on 01248 430411.

Due to regulations, rescued turtles cannot be kept on public display.