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Diego and 14 other male tortoises have returned to their native Española, one of Ecuador’s Galápagos islands.
The tortoises were put out to pasture on Monday after decades of reproducing in captivity on Santa Cruz Island.
The breeding programme was a success, producing more than 2,000 giant tortoises given that it began in the 1960 s.
Diego, aged 100, is believed to have fathered hundreds of progeny, around 40%of the 2,000 huge tortoises alive today by some price quotes.