A tortoise who helped save his species from extinction by having hundreds of children will be released into his homeland after spending eight decades away, conservation authorities have said.

Diego earned a reputation for having lots of sex during a captive breeding scheme for giant tortoises in the Galapagos Islands, and the 100-year-old has now reportedly fathered over 800 children.

He will soon be released into the wild on his native Espanola Island after officials said the programme – which recruited Diego from San Diego Zoo four decades ago – has been a success.

Around 40 per cent of the new tortoises on the island are Diego’s descendents, according to Galapagos Conservancy.

“Diego, who is over 100 years old, will return to his home island almost eight decades after being extracted from it,” the conservation body said.

Jonathan the Giant Tortoise has his first bath after 184 years Show all 5 1 /5 Jonathan the Giant Tortoise has his first bath after 184 years Jonathan the Giant Tortoise has his first bath after 184 years Jonathan takes a bath Vet Joe Hollins gives the 184-year-old tortoise an overdue clean. St Helena Government Jonathan the Giant Tortoise has his first bath after 184 years Jonathan takes a bath The vet gently washed his enormous shell. St Helena Government Jonathan the Giant Tortoise has his first bath after 184 years Jonathan takes a bath Jonathan is one of many Giant Tortoises residing at the Plantation House on St Helena. St Helena Government Jonathan the Giant Tortoise has his first bath after 184 years Jonathan takes a bath Jonathan is something of a an in his home of St Helena, he even features on the back of five pence pieces. St Helena Government Jonathan the Giant Tortoise has his first bath after 184 years Jonathan takes a bath The vet says looking after Jonathan, the oldest living land animal in the world, is "an honour". St Helena Government

The population of the Chelonoidis hoodensis species has gone from 15 to 2,000 since the scheme started around 40 years ago, according to Jorge Carrion, the Galapagos National Park director.

“The island’s ecosystems currently have adequate conditions to support the growing population of tortoises,” he added.

The national park service believes Diego left the Galapagos Islands 80 years ago during a scientific expedition, the BBC reported.

He became one of three male tortoises involved in the breeding scheme – which involved 12 females – after being recruited from the US zoo where he had been living for 30 years, Galapagos Conservancy said.

Diego is currently in quarantine before he returns into the wild on Espanola Island along with other tortoises in March, according to authorities.

“The island has sufficient conditions to maintain the tortoise population, which will continue to grow normally,” said Washington Tapia, the director of the Giant Tortoise Restoration Initiative.

A species of giant tortoise that was believed extinct was discovered on another Galapagos island earlier this year, Ecuador's government said.