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Lost Galapagos rail reappears after nearly two centuries
The near-flightless Galapagos rail, absent from Floreana Island since Charles Darwin's 1835 visit, has unexpectedly returned following the eradication of rats and feral cats. Conservationists describe the bird's reappearance as a stunning recovery milestone in the island's ecological restoration.
Predator removal sparks rapid ecosystem revival
In late 2023, a decade-long effort to eliminate invasive predators on Floreana culminated in the removal of rats and feral cats. By 2025, surveys revealed a surge in native species, including Galápagos doves, lava lizards, geckos, and the dark-billed cuckoo. The most dramatic discovery, however, was the Galapagos rail, last documented on the island by Darwin himself.
"The rail's return was completely unexpected," said Paula Castaño, a wildlife veterinarian with Island Conservation. "It simply reappeared, suggesting a small, hidden population may have persisted undetected." Paola Sangolquí, a marine biologist with the Jocotoco Conservation Foundation, added, "Now, the birds are everywhere-visible and vocal. It's astonishing."
Finches experiment with new songs in predator-free environment
Beyond the rail's return, scientists have observed unprecedented behavioral changes in Floreana's finches. Sonia Kleindorfer, a behavioral biologist at the University of Vienna, reported that young finches are now singing entirely new tunes, a phenomenon never recorded on the island before.
"For 20 years, we documented the same narrow repertoire of songs," Kleindorfer said. "But this year, young finches are experimenting with bold, unfamiliar sounds-like 'Choo-waa!' or buzzing 'Bzz-pshee!'-completely deviating from traditional patterns."
The shift reflects a broader cultural transformation among the finches. Previously, predators forced the birds to conform to a limited set of songs to avoid detection. "In a high-predator environment, standing out meant higher risk," Kleindorfer explained. "Now, with rats and cats gone, the birds are free to innovate."
Survival rates soar as threats diminish
The eradication effort has dramatically improved survival rates for native species. The medium tree finch, once critically endangered due to predation and parasitic flies, has seen a remarkable rebound. "Nest success is off the charts," Kleindorfer noted. "We've never seen so many fledglings survive."
To protect native owls from poisoned rat carcasses, they were temporarily relocated during the eradication. Meanwhile, the avian vampire fly, which deformed finch beaks and hindered mating, is being controlled through insecticide-treated nesting materials.
Restoration project aims to reintroduce lost species
The Floreana restoration project, led by the Galapagos National Park Directorate and partners including the Charles Darwin Foundation, plans to reintroduce 12 species that vanished from the island after Darwin's visit. These include birds and giant tortoises, sourced from breeding programs and other islands. Reintroductions are expected to begin in 2026.
"Floreana is transforming in real time," said Birgit Fessl, principal investigator of landbird conservation at the Charles Darwin Foundation. "The rail's rediscovery is just the beginning."
Darwin's legacy and the future of evolution
The Galapagos Islands, where Darwin developed his theory of natural selection, continue to offer insights into evolutionary processes. Historian Frank Sulloway of the University of California, Berkeley, noted that the archipelago's closely spaced islands showcase how species adapt to distinct environments.
"Darwin recognized invasive species as a 'great plague' disrupting stable ecosystems," Sulloway said. "Today, we're witnessing the reverse: removing those predators allows native species to recover and innovate."
Kleindorfer anticipates further behavioral evolution among the finches, particularly in how females respond to new songs and behaviors. "Which traits will flourish or fade? The answers could redefine our understanding of behavioral evolution," she said.
A testament to resilience
For locals like Sangolquí, the rail's return is deeply personal. "After 200 years, this island proves how resilient species can be," she said. "It's a reminder that recovery is possible-even against the odds."
