hula valley hula valley The environmental conditions of the Hula Valley have helped protect a species of threatened frog for more than a million years. (Protasov AN/Shutterstock)

How one extinct species returned to thrive

The Hula painted frog, ruled extinct in 1996, now lives happily in the swamps of the Hula Nature Reserve.

With humanity directly responsible for what's being termed "the sixth mass extinction" of species in our planet's history, finding any good news for populations on the brink is hard to come by.

The Hula painted frog, located in Israel's Hula Valley, was once thought lost to time. Nicknamed a "living fossil," the amphibian is the only surviving member of an otherwise long-extinct genus of frog (Latonia), known only from fossils dating back millions of years. According to Rebecca Biton, a researcher at Hebrew University of Jerusalem's Institute of Archaeology, the environmental conditions of the Hula Valley have played a major role in the species' resilience through the ages.

"The Hula Valley climate in the last million years probably included some colder and warmer periods compared to today's climate, but overall the climate was always a temperate Mediterranean climate; especially when compared to the fluctuations that Europe went through in the last million years," Biton told From the Grapevine. "Moreover, in the last million years there was always a relatively large and shallow lake and adjacent streams and springs."

Unfortunately for the Hula painted frog, those critical springs and lakes were dramatically reduced by up to 90 percent during an agriculture drainage project in the early 1950s. Despite efforts by conservation officials in the early 1990s to reflood portions of the Hula Valley, the frog in 1996 became the first amphibian to be declared extinct by an international organization. Its rediscovery in a small section of the Hula Nature Reserve in 2011 elated researchers and highlighted the need for further environmental protections. 

"The numbers of specimens is very small and their geographic range is constrained to two spots so far; this increases the risk that the species might go extinct," said Biton. "Any disturbance or change in their environment such as pollution, flooding or drying, etc. of their very limited area will be very dangerous to the survival of this rare endemic species." 

Hula painted frogA female Hula painted frog found at Lake Hula in 2011. (Photo: Mickey Samuni-Blank/Wikimedia Commons)

Yifat Artzi, an ecologist at The Hula Nature Reserve, told From the Grapevine that studies of threatened species offer important lessons for both habitat preservation and future conservation efforts. 

"Archaeozoological studies of amphibians and reptiles hold great potential for providing valuable information on past human behavior, but also help us to reconstruct past environments and climate," Artzi said. "In this respect the Hula painted frog study is a good example that combined studies, of both past and present species distribution, and is the essential basis for establishing management and conservation programs for species facing extinction."

Today, the location of the dozen or so Hula painted frogs in the Hula Nature Reserve remains something of a mystery. The frogs are extremely hard to find, with many seeking refuge under dense vegetation (in some cases, several inches down) and staying close to one pond in the reserve. According to Biton, knowing they're out there is enough to encourage conservationists that some precious previously lost habitat of the Hula Valley is thriving.  

"Although a lot of efforts are made to search for Hula painted frog specimens and to investigate them, still a lot is yet unknown about their biology and habitat requirements," she said. "Therefore, the authorities in charge are very conservative in their approach; they try to maintain the conditions in the nature reserve habitat as it was since the reserve was established."


Photos and SlideshowsPhotos and Slideshows

Related Topics: Animals

How one extinct species returned to thrive
The Hula painted frog, ruled extinct in 1996, now lives happily in the swamps of the Hula Nature Reserve.