10/06/2025
32 harlequin frog species once thought extinct seemingly back from the dead.
For decades, harlequin frogs were considered among the hardest-hit victims of the global amphibian crisis. A deadly fungal disease, combined with habitat loss and climate change, devastated populations across Central and South America. Many species were declared “possibly extinct.”
However, a comprehensive study by Michigan State University and Ecuadorian researchers has revealed a striking turn: up to 32 species once believed gone are still alive. The findings, published in Biological Conservation, combine literature reviews, field expeditions, and genetic analyses – providing the clearest evidence yet that these rediscoveries are not isolated flukes, but part of a larger survival story.
Some examples are striking. Species like the harlequin frogs of Ecuador were thought to have disappeared decades ago, yet small populations persist in remote habitats, often thanks to protection from local and Indigenous communities. These frogs, brightly patterned and culturally significant, are now symbols of both fragility and resilience.
But scientists stress caution: rediscovery does not equal recovery. Nearly all of these species remain critically endangered, with small, fragmented populations vulnerable to the same threats that pushed them to the brink. Their survival will depend on urgent conservation – from habitat protection and disease monitoring to captive breeding programs.
“This gives us a glimmer of hope,” said lead researcher Kyle Jaynes. “But it also reminds us that without active intervention, rediscovered species could still vanish.”
The study shows that extinction is not always absolute. Sometimes, species persist against all odds – but whether they thrive again depends entirely on what we do next.
Read the study:
“Harlequin frog rediscoveries provide insights into species persistence in the face of drastic amphibian declines.” Biological Conservation, 8 November 2022.