 The 15 remaining tortoises were brought to the Charles Darwin Research Station in 1971 for a captive breeding program and, in the following 33 years, they gave rise to over 1,200 progeny which were released onto their home island and have since begun to reproduce naturally.One of the tortoises, Diego, is one of the main drivers of a remarkable recovery of the "hoodensis" species, having fathered between 350 and 800 progeny.The Galápagos National Park Service systematically culls feral predators and competitors.