Adiós, Toughie: The Last Known Rabb’s Fringe-Limbed Tree Frog Dies in Atlanta

Since his discovery in 2005, Toughie the frog has been the face of amphibian extinction

Toughie
Toughie Wikimedia Commons

By some estimates, dozens of species go extinct on planet Earth each day. That means there are likely hundreds or thousands of animals living out their last days as the only surviving member of their species. But few of them have a name, or even a Wikipedia page like Toughie, the last known Rabbs’ fringe-limbed tree frog, who passed away at the Atlanta Botanical Gardens late last week.

In 2005 Researchers collected Toughie in Panama during a trip to nab as many amphibian species as possible to protect them from chytrid fungus, a skin disease that can have a 100 percent mortality rate among frogs, reports Brian Handwerk for National Geographic, 

Toughie was one of the lucky ones. Handwerk reports that 85 percent of the amphibians in the area in which Toughie was collected were wiped out by the disease. “It was likened to just rescuing things from a burning house,” Mark Mandica, Amphibian Conservation Coordinator at Atlanta Botanical Garden, told Handwerk. It was Mandica's then two-year-old son who bestowed the lucky amphibian with the moniker Toughie.

It turned out that Toughie was also new to science, and his species, Ecnomiohyla rabborum, was officially recognized in 2008. According to Arkive.org, researchers attempted a captive breeding program for the frog, but it did not succeed. The species is unique among frogs. The male of the species finds a water-filled hole in a tree then calls to attract a female. She lays eggs in the cavity then leaves the male to protect the eggs and tadpoles. As they grow, the male allows the tadpoles to scrape off small flecks of its skin to feed on.

In 2008, researchers heard the species' call in the same area that Toughie was collected, but none have been seen or heard in the wild since. Another male of the species was euthanized at Zoo Atlanta in 2012 after suffering failing health, making Toughie the last of his kind. 

At least one herpetologist holds out hope that Toughie has some relatives back in Panama and that the species may remain hiding somewhere in jungle. “The habits of this genus can make them extremely difficult to find if they remain high up in the trees,” Jonathan Kolby, director of the Honduras Amphibian Rescue and Conservation Center tells John Platt at Scientific American. “Being that this species breeds in tree cavities up in the canopy, I would hope that this behavior offers some protection from exposure to chytrid fungus, although the species was reported to have become much less common after the arrival of chytrid in the region.”

Even if his species is not re-located, Toughie has made a lasting impression. Photographer Joel Sartore took photos of him for his Photo Ark project, which documents species on the brink of extinction. Sartore tells Handwerk that celebrities including race car drivers and movie directors came to meet Toughie. “A lot of people were moved to tears when they saw him,” says Sartore. “When you have the very last of something it’s a special deal.”

Toughie was one of several endangered animals whose image was projected onto St. Peter’s Basilica during the Paris Climate Talks last year.

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