Nearly 150 years after the last giant tortoises were removed from Floreana Island in Ecuador’s Galapagos archipelago, the species made a comeback recently, when dozens of juvenile hybrids were released to begin restoring the island’s depleted ecosystem.
The 158 newcomers, aged eight to 13, have begun exploring the habitat they are destined to reshape over the coming years.
Their release was perfectly timed with the arrival of the season’s first winter rains.
"They are large enough to be released and can defend themselves against introduced animals such as rats and cats,” said Fredy Villalba, director of the Galapagos National Park breeding centre on Santa Cruz Island, noting that the best specimens with the strongest lineage were selected specifically for Floreana.
These released juvenile specimens, out of a total of 700 planned for Floreana, will be introduced gradually.
According to Christian Sevilla, director of ecosystems of the Galapagos National Park, they carry between 40% and 80% of the genetic makeup of the Chelonoidis niger – a species that has been extinct for 150 years.
The lineage of these hybrids traces back to Wolf Volcano on Isabela Island, a discovery that still puzzles scientists today.
By selecting adults with the strongest genetic makeup, said Sevilla, the breeding programme aims to gradually bring the extinct Floreana species back to its former purity.
Two centuries ago, Floreana was home to approximately 20,000 giant tortoises. However, whaling, a devastating fire, and relentless human exploitation eventually led to their complete extinction on the island.
"In genetic terms, reintroducing a species to that island with a significant genetic component of the original species is vital,” said biologist Washington Tapia in an interview.
Tapia, a researcher and director of Biodiversa-Consultores – a firm specialising in the Galapagos Islands – emphasised that this process is about more than just numbers; it is about restoring a lost lineage.
Floreana, an island spanning approximately 173sq km, is a volcanic landmass and the southernmost point of the Galapagos archipelago.
Situated in the middle of the Pacific Ocean – roughly 1,000km from the mainland coast – it remains a remote and vital ecological site.
The tortoises reintroduced to Floreana will share their territory with a diverse population of nearly 200 people alongside flamingos, iguanas, penguins, sea gulls and hawks.
However, they must also contend with introduced plant species such as blackberry and guava, as well as animals like rats, cats, pigs and donkeys.
These non-native species, introduced by human activity, represent potential threats to the island’s newest inhabitants.
Floreana resident Veranica Mora described the release of the turtles as a dream come true. "We are seeing the reality of a project that began several years ago,” she said, adding that the community feels immense pride in the return of the giant tortoises.
The United Nations designated the Galapagos Islands as a Natural World Heritage Site in 1978. This honour recognises the islands’ unique abundance of terrestrial and marine species found nowhere else on the planet. – AP
