Giant tortoises reclaim Floreana Island in Galápagos after 150 years

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Floreana Island in Ecuador’s Galápagos archipelago is welcoming giant tortoises back for the first time in more than 150 years, as the Galápagos National Park released 158 juvenile hybrid animals on Friday. The park said the young tortoises—aged 8 to 13—were staged to start restoring the island’s depleted ecosystem, with the release timed for the season’s first winter rains.

Park officials said the juveniles were chosen for their ability to survive once introduced, including protection against non-native predators. “They are large enough to be released and can defend themselves against introduced animals such as rats and cats,” Fredy Villalba, director of the Galápagos National Park breeding center on Santa Cruz Island, said, adding that the best specimens with the strongest lineage were selected specifically for Floreana.

The release forms part of a larger effort that will bring more tortoises to the island over time. Villalba said the 158 newcomers came from a planned total of 700 juvenile hybrids for Floreana, with animals introduced gradually as the project proceeds. Christian Sevilla, director of ecosystems of the Galápagos National Park, said the hybrids carry between 40% and 80% of the genetic makeup of Chelonoidis niger, a giant tortoise species that has been extinct on Floreana for 150 years.

Sevilla said the hybrids’ lineage traces back to Wolf Volcano on Isabela Island, a connection he said still puzzles scientists. By selecting adults with the strongest genetic makeup for breeding, he said, the program seeks to gradually bring back the Floreana species toward its former “purity.”

The conservation effort is also framed as a restoration of ecological roles as well as genetics. Conservationists said Floreana’s giant tortoises once numbered around 20,000, but whaling, a devastating fire and sustained human exploitation ultimately pushed them to extinction on the island. Washington Tapia, a biologist and director of Biodiversa-Consultores, said that reintroducing animals with a significant genetic component of the original Floreana species is essential, and he described the effort as more than simply meeting numbers.

Tapia told The Associated Press: “In genetic terms, reintroducing a species to that island with a significant genetic component of the original species is vital.” He emphasized that the process is also about restoring a lost lineage, rather than treating the reintroduction as a purely quantitative exercise.

Floreana, about 173 square kilometers (67 square miles), is described by the park as a volcanic landmass in the southern part of the Galápagos archipelago, located roughly 1,000 kilometers (621 miles) from the mainland coast. Alongside the near-200 residents on the island, officials said the reintroduced tortoises will share habitat with other species including flamingos, iguanas, penguins, sea gulls and hawks.

Officials also said the tortoises will face pressures from introduced species, including non-native plants such as blackberry and guava and introduced animals including rats, cats, pigs and donkeys. Those threats, conservationists said, are an additional challenge for the juveniles as they begin exploring the habitats their predecessors once shaped.

Floreana resident Verónica Mora described the release as meaningful for the community. “We are seeing the reality of a project that began several years ago,” she said, adding that the community feels pride in the return of the island’s giant tortoises.

The Galápagos Islands were designated a Natural World Heritage Site by the United Nations in 1978, recognizing the archipelago’s unique terrestrial and marine species found nowhere else on Earth. The park’s release on Floreana marks the newest step in efforts to rebuild ecosystems after human-driven extinctions erased entire species lineages from the island.