Giant tortoise believed extinct confirmed alive in the Galapagos Islands

Giant tortoise believed extinct confirmed alive in the Galapagos Islands




ecosystem

A team of conservationists and explorers in 2019 were astonished with a discovery of a lone female giant tortoise.


In this Jan. 25, 2020 photo released by Galapagos National Park shows park workers inspecting a tortoise near Wolf Volcano on Galapagos Islands, Ecuador. Tui De Roy/Galapagos National Park via AP

By Sammy Westfall, Washington Post

June 16, 2022 | 8:17 AM

The “fantastic giant tortoise” — a scarce Galapagos species with a huge, flared shell — has only been identified once, more than a century ago, in 1906. It’s since widely been considered extinct.

But that’s not the case, researchers found this week.

Hints that the mysterious species has lived on have arisen over the century — including 1960s reports of tortoise scat on the subspecies’ native Fernandina Island, which is the Galapagos’ youngest, most pristine and most volcanically active island. But anecdotes and rumors were “tenuous at best,” researchers told The Post.

So, a team of conservationists and explorers in 2019 were astonished with a discovery on the tough island: a lone female giant tortoise. They named her Fernanda.

Though she was the first tortoise discovered on the island since the 1906 seeing, researchers were not sure she was of the same subspecies — or Fernandina Island tortoise — long thought to be extinct. In fact, many ecologists doubted it.

Fernanda seemed not to be native to Fernandina Island. Perhaps she had floated from a different island, or was taken in a storm, or moved by seafarers, some thought, according to a Princeton University release.

But by sequencing her complete genome, and setting it next to the historical specimen genome collected in 1906, researchers this week confirmed that the tortoises, a century apart, were of the same long-considered-extinct lineage: the fantastic giant tortoise — “with a current known population size of a single individual.”

That method she’s considered an “endling,” or the last known individual in a species or subspecies.

Because a species is only declared extinct after exhaustive efforts taken to locate any survivors, “it’s extremely scarce for an individual to be found like this — especially after 100 years,” the study’s co-first-author Stephen Gaughran told The Post.

There are around 13 other species of Galapagos Island tortoise — all of which descended from the same ancestor. Twelve species are nevertheless living, though all are under threat, from unprotected to critically abundant. One species has long been extinct — and another lineage famously ended in 2012, with the death of endling Lonesome George.

Fernanda is small relative to her species, but she is estimated to be more than 50 years old, possibly due to stunted growth and limited vegetation in her home, the study noted.

When Fernanda was first spotted in 2019, Wacho Tapia, Galapagos-based director of the Giant Tortoise Restoration Initiative, wrote that “the emotional high” he experienced in finding a live tortoise on the far away, seemingly uninhabitable island was “indescribable.”

Upon starting a five-day “mega-expedition” of the difficult-to-analyze island of Fernandina, Tapia tempered his expectations, writing that he knew the possibility of finding a tortoise was “near zero” given that no tortoise had been found on the island in 113 years.

But while venturing around, Jeffreys Málaga, a Galapagos National Park Directorate ranger on the expedition, called out “Tortoise!” and Tapia felt “hope and excitement bubble up.”

There, they found Fernanda, relaxing in a identify between some rocks and plants.

She loves eating cacti, Tapia wrote, and is “healthy and very active” each morning. She is now living at the giant tortoise breeding center of the Galápagos National Park.

The island’s volcanic activity led some to fear the worst for the species — “those tough conditions are likely what made it possible for Fernanda to avoid notice for all these years,” Gaughran wrote to The Post. “Expeditions to the island can be difficult, so there are likely many places for tortoises — already giant ones! — to hide.”

Now that they’ve found Fernanda and confirmed that she is a member of the once-considered-extinct species, conservationists have to begin drawing the species away from the brink.

“The finding of one alive specimen gives hope and also opens up new questions, as many mysteries nevertheless keep,” said ecologist Adalgisa Caccone, a senior author of the study, to Princeton University. “Are there more tortoises on Fernandina that can be brought back into captivity to start a breeding program?”

It’s gone different ways in the past.

The study noted the success of 3,000 individual tortoises of the Espanola Island species being recovered from only a dozen surviving females and three males by a dedicated captive breeding program. One tortoise, Diego, is father to upward of 800 offspring. The breeding program was so successful that it was retired.

however, there was Lonesome George — who had an “apparent aversion to female tortoises,” National Geographic reported, and failed to copy before dying in 2012, becoming the last of the Pinta Island subspecies.

For now, there are no known tortoises in her subspecies for Fernanda to begin breeding with.

already if Fernanda is the last fantastic giant tortoise, the study’s authors say that her genome sequencing is already helping them learn more about the evolution of giant tortoises.

And Fernanda is “becoming a conservation icon,” hopefully inspiring others to care more about biodiversity and the extinction crisis, Evelyn Jenson, a biologist and molecular ecologist who co-authored the study, told The Post.

But the researchers, and other conservationists, are not giving up however.

Tapia wrote that year that he now has hope that tortoises exist in other parts of the island with similar environmental conditions.

If others exist, they’ve successfully evaded detection during wide searches of the island, the study wrote. But researchers noted that encouraging signs of other tortoises — from scat to tracks — have been found on Fernandina. Expeditions are planned for the near future to look for them.

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