For the first time, New Zealand's critically endangered Archey's frog - the world's most evolutionarily distinct amphibian - has been successfully bred from a long-term captive population at Auckland Zoo.
Seven Archey's frog babies that hatched at the Zoo in early December from fertile eggs laid in October, are continuing to thrive. Over 50 million years old and described as "living fossils", Archey's frogs, like New Zealand's other three endemic frog species, don't have a tadpole stage like other frogs. Instead, the Archey's 'tadpole' grows rudimentary limbs inside the egg, and then hatches out as an almost fully formed frog. The seven baby frogs, each just a half a centimetre long, have absorbed their yolk sacs and progressed to a diet of tiny invertebrates.
While Archey's frogs have been bred twice before elsewhere in captivity, the babies - from adult frogs that had not long been collected from the wild - did not survive.
"It's a massive step forward to finally breed these enigmatic and extremely sensitive little frogs after almost eight years," says Auckland Zoo NZ Fauna curator, Richard Gibson.
"While a slow process, perfecting husbandry and furthering our understanding of Archey's reproductive biology is all part of developing a skill set that provides the best possible chance of conserving this frog in the wild - where it's battling the combined threats of habitat disturbance, introduced predators, disease and climate change," says Mr Gibson.
International experts agree the breeding of Archey's frogs is a huge achievement.
Kevin Zippel, programme director of the Amphibian Ark (AArk) - a world body focussed on the global survival of amphibians using captive breeding for species that can't be safeguarded in nature, says: "Conserving any species usually requires a whole range of actions and captive breeding is increasingly a requirement for many threatened amphibians. Auckland Zoo's recent success with Archey's frog is exciting news and represents an important breakthrough".
Professor Jonathan Baillie, Director of Conservation Programmes at the Zoological Society and London and the driving force behind the EDGE of Existence - a programme set up to highlight and conserve one-of-a-kind species on the verge of extinction, says "breeding one of the most primitive and threatened species on the planet is an amazing achievement and a major breakthrough for conservation". "It will help to ensure the future of the world's most 'Evolutionarily Distinct & Globally Endangered' (EDGE) amphibian and its truly fascinating parenting practices," says Professor Baillie.
Auckland Zoo is the only facility in the world to hold Archey's frogs, which it does with the blessing of Hauraki whanui iwi and Marokopa-Kiritihere iwi.
While not currently on display, visitors to Auckland Zoo will soon be able to see adult Archey's frogs in the Zoo's Night Forest habitat within its New Zealand precinct, Te Wao Nui.
Archey's frog (Leipelma archeyi)