Discovery of the world's rarest tree frog is caught on camera
BBC News has been following a team from Manchester University and Chester Zoo as they trek deep into Costa Rica's rainforest to work on conservation programmes for critically endangered amphibians.
Here the biologists explain why they believe that safeguarding the future of amphibians is key.
Of course, rediscovering the golden toad was always going to be a remote possibility - it has been gone so long
The Golden Toad proved elusive
But just to visit the place where they were last seen - the unique elfin forests of Monteverde where they used to appear like ghosts from nowhere at the first sign of rain, reproduce hurriedly in an explosion of colour, and then disappear as quickly as they had arrived - well, it is little short of a religious experience for a frog biologist.
So we followed the trail, we saw the moss and lichen encrusted network of roots that Bufo periglenes used to call home - but did not see a thing.
But that was not the main reason why we were here.
Costa Rica, like many parts of the world, has suffered devastating losses of amphibian species in recent decades.
Understanding why is crucial both to preventing, or at least stemming, similar losses elsewhere and perhaps to helping the recovery process right here.
Over the last few years, a number of "extinct" species have reappeared in one or two remote locations, their rediscovery largely a result of the efforts of a handful of dedicated frog enthusiasts.
Very rare: Isthmoyla rivularis
Take Isthmohyla rivularis, for example.
Until a single male was spotted last year, this species was thought to have been extinct. This week, another male has been seen, but far more importantly a female, full of eggs.
This means the species is still out there with the capacity to reproduce, though extensive surveys along the streams they inhabit suggest that they are still desperately rare.
Now we know they are here, the next challenge is to learn all we can about them so we are better able to conserve them.
Another sensational rediscovery in the recent past was the aptly named green-eyed frog (Lithobates vibicaria).
The green-eyed frog is only found in a few remote spots
This spectacular frog was once widespread in the high-altitude forests of the Monteverde region and having also been thought extinct, it is now known to be hanging on in just one or two isolated and inaccessible areas.
Though part of the strategy for assuring this species' continued existence has been to establish a conservation breeding programme at the University of Manchester and Chester Zoo, the focus is now upon monitoring these precious wild sites for any sign of change - good or bad - and surveying other similar areas for more frogs.
Studying the populations of both of these rare frogs, and others like them, is critical if we hope to conserve them in the long term.
In doing this, collaboration is key.
Just as important as finding the frogs has been meeting with our Costa Rican colleagues from the Monteverde Rainforest League and the Tropical Science Center.
These two organisations are jointly responsible for establishing the forest reserves and for their continuing protection.
Both are passionate about biodiversity, and are eager to develop a collaborative amphibian conservation and research strategy.
So, we leave Costa Rica elated by our finds and excited by the prospects for the future of this country's amphibians.
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