With the establishment of the Galápagos National Park Directorate and the Charles Darwin Research Station in 1959, a review of the tortoise populations was initiated. On Pinzón there were some 100-200 giant tortoises, all old adults. No young were found. Black rats, introduced to the island in the late 1800s, had apparently consumed all tortoise eggs and/or hatchlings for most of the 20th century. In 1965, the first eggs were brought from the natural tortoise nests on Pinzón and the tortoise rearing program was begun. Since the first 20 tortoises were repatriated to Pinzón in 1970, over 800 young tortoises have been released there.

The first attempt to eradicate the black rats was carried out in 1988-89; after several months of not finding any rats, they eventually began to reappear indicating that the campaign was a failure. With new methodologies (mainly the systematic release of poisoned bait from a helicopter), a successful rat eradication campaign was carried out by the GNPD and its collaborators in December 2012. In December 2014, a tortoise survey on Pinzón indicated continued growth and survival of the repatriates, the ongoing presence of many of the original native tortoises, and, for the first time in over 100 years, substantial numbers of native-born hatchlings — indicating successful in situ reproduction.

Data from a recent monitoring trip investigating the relative abundance of landbirds, seabirds, other reptiles and invertebrates are now being processed. A first look at the endemic land snail survey data indicates that native snails are generally more abundant and widely distributed across the island since the rat eradication.