In 2004, researchers published first ever Global Amphibian Assessment. It reported that one third of the world’s 5,743 known amphibian species were threatened with extinction. A 2014 assessment painted an even grimmer picture for amphibians, estimating that over 40% of known amphibians risk extinction. It wasn’t until then that the true scale of the amphibian crisis became widely known.

It’s clear that zoos are positioned to play an important role in amphibian conservation, especially as there aren’t any overwhelmingly effective mechanisms for managing the spread of chytrid fungus in the wild. Captive assurance populations are almost necessary to ensure the long-term survival of many species.

It’s been more than a decade since the Global Amphibian Assessment (GAA) was conducted, and Durrell Wildlife Conservation Trust researcher Jeff Dawson wondered whether zoos and aquariums have stepped up to the plate. The GAA sounded an amphibian alarm. Have zoos responded?

The stumbling block is that zoos aren’t only in the business of wildlife conservation, though that is an important component of what they do. There are reasonable criticisms of zoos’ role in conservation, from the value of ex situ conservation in the first place, to an overall bias in the way zoos curate their collections. And while zoos have played critical roles in the recovery of at least 17 vertebrate species and are the world’s third largest provider of in situ conservation funding, their funding of in situ amphibian conservation projects is disproportionately low compared with other taxa. The story of the Kihansi spray toad is compelling but rare.

While it’s known that the overall number of amphibian species held in zoo collections has increased, “whether the proportion of threatened species held has changed over time is unknown,” writes Dawson. But it’s easy to figure out.

All accredited zoos contribute data about their holdings to the International Species Information System (now Species 360) (ISIS). From it, Dawson and his team extracted amphibian data for all registered institutions from 1994 through 2014. That’s ten years prior to the GAA, and ten years since.

Over the 20-year timespan they considered, 695 amphibian species were held at least once in a total of 848 zoos and aquariums. Of those, 143 were classified as globally threatened. That’s equivalent to nearly 11% of all known amphibian species, and 7.3% of globally threatened amphibian species.

After the GAA was published in 2004, zoos didn’t change the speed at which they added new species to their collections, but they did accelerate their inclusion of globally threatened ones. And it wasn’t just a small number of zoos leading the charge; the change could be seen throughout the system. In 1994, a threatened species would be held on average in 2.8 zoos. By 2014, that more than doubled, to an average of 6.8 zoos.

And when threat level was considered, critically endangered species were most popular, held on average by the highest number of individual zoos.

But zoos’ inclusion of amphibians in general—and threatened amphibians in particular—is not without problems.

In 2014 zoological collections were overwhelmingly composed of species from North America, Europe, and Oceania, while those from South America and Asia were fairly poorly represented.

The proportion of zoo collections containing globally threatened species, while improved, had stayed far too low at 7.3%. Nearly 93% of the planet’s threatened amphibians remain completely absent from zoological collections. (On the other hand, most zoos in Asia, Africa, and South America don’t contribute their data to ISIS, so it’s hard to say whether they are doing a better job of conserving their own local species.)

It’s not just that amphibians are a second thought to most zoo-goers. “It’s challenging to exhibit amphibians,” admits herpetologist Mark Mandica, Amphibian Conservation Coordinator at the Atlanta Botanical Garden (and the man behind the popular FrogsNeedOurHelp Instagram account). “We have a few species right on exhibit, but they’re so cryptic that most people think that they’re a leaf, or something on a leaf.” Still, with the right educational program, some people might be swayed away from the pandas and polar bears. “I try to get the message to children. Most kids still have their priorities straight. They get concerned when you tell them that the amphibians are disappearing all over the world,” he adds.

Even if global zoo holdings for amphibians continued to increase at the same rate as they have the last 20 years, it would take another 20 years to reach a target of 40% globally threatened species, a proportion representative of the real world. Many species may not survive that wait. – Jason G. Goldman | 20 January 2016

Source: Dawson, J., Patel, F., Griffiths, R. A., & Young, R. P. (2015). Assessing the global zoo response to the amphibian crisis through 20-year trends in captive collections. Conservation Biology, 30(1), 82-91. DOI: 10.1111/cobi.12563.

Header image: Hylomantis lemur is a critically endangered tropical frog at risk from both habitat loss and the chytrid fungus – via shutterstock.com

