As colorful frog leaps toward extinction, scientists look for clues
The University of Manchester
October 29, 2007
Frog study takes leaf out of nature's book
Biologists from The University of Manchester have teamed up with experts at Chester Zoo in the hope that their findings will not only help save the splendid leaf frog Cruziohyla calcarifer from extinction in the wild but provide clues as to how it can be better catered for in zoos and aquariums.
Loss of habitat in its native Costa Rican rainforest, combined with global declines in amphibian populations generally through a combination of environmental change and disease, have all contributed to the splendid leaf frog's precarious situation.
"This research aims to contribute to our understanding of the basic factors that influence the development and survival of these frogs," said Dr Richard Preziosi, a lecturer in the University's Faculty of Life Sciences, who is supervising the project.
The splendid leaf frog. Courtesy of the University of Manchester
Frogs avoid damaging UV-B radiation, reducing extinction risk
Poison arrow frogs appear to make special effort to avoid exposure to damaging ultraviolet-B radiation, according to research published in the journal Biotropica. The findings are significant in light of increasing levels of UV-B radiation due to ozone depletion.
Bad news for frogs; amphibian decline worse than feared
Chilling new evidence suggests amphibians may be in worse shape than previously thought due to climate change. Further, the findings indicate that the 70 percent decline in amphibians over the past 35 years may have been exceeded by a sharp fall in reptile populations, even in otherwise pristine Costa Rican habitats. Ominously, the new research warns that protected areas strategies for biodiversity conservation will not be enough to stave off extinction. Frogs and their relatives are in big trouble.
"The global decline in amphibian populations means research such as this, carried out ex situ, is therefore critical for both conservation projects in the wild and for maintaining and successfully breeding the frogs in zoos and aquariums."
The research at Chester Zoo is being complemented by field studies being conducted by Dr Preziosi and Manchester Museum's Curator of Herpetology, Andrew Gray, in the Costa Rican jungle.
"The combination of our fieldwork and the project at Chester Zoo will provide us with a much better idea of the nutritional requirements of this species," said Dr Preziosi.
"In the wild these animals live in the tree canopy of the rainforest and are exposed to sunlight for long periods of time, so this study will also examine the effect that ultraviolet rays have on the fitness and viability of captive-bred frogs."
Nearly a third of the world's 6,000 amphibian species are threatened with extinction and more than 120 species have already vanished from the planet.
Across the globe, conservation organisations and professionals are mobilising efforts to help save as many of these species as possible.
As part of the response, a new organisation known as the Amphibian Ark (AArk) has been set up to help other conservation organisations assist in the effort.
Kevin Buley, Head of Zoo Programmes at Chester, said: "This study will help benefit the conservation breeding of amphibians in European zoos and aquariums.
"As such, it will also help to save many critically endangered species from extinction as part of the global amphibian ark initiative."