After saving his species, frisky tortoise Diego to retire to Galapagos island home

An elderly giant tortoise whose remarkable sex drive has helped to save his species from extinction is about to be retired.

Diego will retire to his original habitat on Espanola Island after more than 80 years. Picture: AP

An elderly giant tortoise whose remarkable sex drive has helped to save his species from extinction is about to be retired from his labours and released into the wild.

Diego, who is believed to be more than 100 years old, has spent 44 years in the Galapagos National Park’s tortoise-breeding program, which has been so successful that it is no longer needed.

Diego was captured on Espanola, the southernmost island in the Galapagos archipelago, sometime between 1900 and 1959. He ended up in the San Diego Zoo and years later was found to belong to a distinct spec­ies, Chelonoidis hoodensis, that was in severe danger of dying out.

By the 1970s only 14 members of the species were left on Espanola, 12 of which were female, and some of them were thought to have gone decades without encountering another of their kind.

Enter Diego. In 1976 he was flown back to the Galapagos, where more than a century earlier Charles Darwin’s observations of variation among finches and giant tortoises led to his landmark work On the Origin of Species.

From a captive breeding centre on Santa Cruz, Diego helped to drive his species’ population up to about 2000. Paternity tests suggest he is responsible for about 40 per cent of the tortoises born via the program.

His achievement is all the more formidable as he had to win over the female tortoises, who choose whether to mate or not. Another male tortoise in the program­ has fathered hardly any offspring. A third is responsible for almost 60 per cent of the new generation, but he lacks Diego’s bold personality and has received far less attention.

The population has rebounded so successfully that the prog­ram can be shut down.

“The island has sufficient conditions to maintain the tortois­e population, which will continue to grow normally,” Washington Tapia, the director of the giant tortoise restoration initiative, said.

Experts are intrigued to discover how Diego’s libido will respond to retirement. “He might actually amp it up,” said James Gibbs, a professor of environmental and forest biology at the State University of New York.

The Times