Land Iguanas have been rewilded and are already reproducing on Santiago Island in the Galápagos National Park, 187 years after a healthy population was last spotted there by Charles Darwin. 

Over the past three years, the Galápagos National Park has released 3,143 Land Iguanas (Conolophus subcristatus) to Santiago Island, one of the Galápagos Islands deep off the coast of Ecuador in the Pacific. 

So far it looks like a huge success, with the lizards’ reintroduction already changing the dynamics of the ecosystem for the better.

“They have opened paths, removed the earth, dispersed the seeds, and this is changing the dynamics; but the greatest results will be observed in a few more years,” Dr Luis Ortíz-Catedral, a scientific adviser of the Galápagos National Park Directorate (GNPD) responsible for the project, said in a statement.

Most encouraging of all, the team discovered individuals in July that hadn’t been labeled or documented, indicating that the population is healthy and reproducing. 

“There has been evidence of reproduction of the iguanas in Santiago, which indicates that their reintroduction process has been successful,” explained Dr Jorge Carrión, the Director of Conservation of the Galápagos Conservancy.

The Galápagos Land Iguana is considered vulnerable to extinction by the IUCN Red List. While the species can be found in larger numbers of other islands of the Galápagos, the last time a healthy population was documented on Santiago was in 1830s by Darwin. 

The Galápagos Islands have almost become synonymous with Darwin. He spent five weeks on the islands in 1835 as part of the second voyage of HMS Beagle, a gigantic journey that spanned from 1831 to 1836 with the aim of surveying the coast of South America. 

When noticing the rich array of biodiversity that was similar from island to island, yet perfectly adapted to each separate environment, it turbocharged the ideas that led him to the theory of evolution by means of natural selection.

Difficult times have fallen on the Galápagos Islands in recent years, unfortunately. Wracked with worries ranging from invasive species to pollution, the islands have seen a number of their animal populations struggle. 

Thankfully, a number of recent conservation projects have helped to turn the tide and the island's biodiversity is starting to bounce back.

“The process of ecological restoration of Santiago Island began several decades ago when efforts began to eradicate the populations of feral pigs, goats, and donkeys, an objective that the GNPD achieved in 2006. Although the challenges to restore the ecological integrity of the island entirely are still large, the return of the Land Iguanas is a key step, as it represents giving back to the ecosystem the missing piece to reestablish its integrity,” added Wacho Tapia, General Director of the Galápagos Conservancy.