But he is not the last. According to the International Union for Conservation of Nature (IUCN), climate change currently threatens nearly 12,000 species.
Those lucky enough to spot them will never forget the sight of these golden toads the size of a child’s thumb emerging from the undergrowth in the Costa Rican jungle. For others it is too late. The little amphibian died out.
A few days a year, an army of these little batrachians mysteriously appeared in the ponds of this tropical forest to reproduce.
“The ground is very dark and the golden toads loomed up like animal figurines. It was quite a sight” amid the “gnarled, wind-shaped, moss-covered trees,” said J. Alan Pounds, an ecologist at the biological reserve of Monteverde in Costa Rica†
But that was before its disappearance, noted in 1990. The Monteverde toad is the first known species whose extinction has been attributed to climate change. A few others have joined him in the grave, and that’s certainly just the beginning.
First species fall on the battlefield of climate change
Even if the world manages to limit warming to +1.5 °C compared to the pre-industrial era – the most ambitious target of the Paris agreement – according to the climate experts at the UN (IPCC), 9% of the species on Earth can disappear.
The golden toad lived alone in the forests of Monteverde. “About 99% of the population was lost in one year,” explains J. Alan Pounds, whose conclusions are corroborated by the IPCC report on the effects of global warming published in February.
When the scientist arrived in Costa Rica in the early 1980s to study amphibians, climate change was not a priority, but his breath was already palpable. After the disappearance of this forest of the golden toad and other amphibians, such as the Monteverde harlequin frog, the researchers compared the evolution of the local climate and that of species populations.
They saw the periodic impact of the El Nino phenomenon, as well as long-term trends related to climate change, with declines occurring after unusually hot and dry spells. Chytridiomycosis also played a big part, for J. Alan Pounds and his colleagues who summed it up: The disease was “the bullet, climate change pulled the trigger.”
“A #metoo movement for species”
A mechanism that repeats itself elsewhere. As for the melomys rubicola, a small rodent that lived on a small moor off the coast of Australia and which no one has seen since 2009. The only mammal endemic to the Great Barrier Reef unable to survive the submersion of its habitat was declared extinct in 2016.
According to the International Union for Conservation of Nature (IUCN), climate change threatens nearly 12,000 species, of which nearly 6,000 are threatened with extinction.
“It’s absolutely terrifying,” said IUCN climate expert Wendy Foden. “We need a #metoo movement for species”.
International negotiations are underway to reach a treaty to better protect nature, in particular by protecting at least 30% of the land and oceans by 2030. But with global warming, this classic protection is not enough, emphasizes Wendy Foden. “Even the most remote wilderness areas will be affected by climate change.”
“Forest of Dust”
In Monteverde, even the clouds have changed. Precipitation in this region has increased over the past 50 years, but has become more erratic, alternating between very rainy and very dry periods, J. Alan Pounds points out.
In the 1970s, this forest had an average of about 25 dry days a year, compared to about 115 in the past ten years. And the fog that enveloped the forest to retain moisture during the dry season, giving this “cloud forest” its name, has been reduced by about 70%.
“Often it looks more like a dust forest than a cloud forest,” laments Pounds.
As for the golden toad, a team of conservationists set out to track it down to its historic habitat in Costa Rica’s “Eternal Children’s Forest” last year after rumors were spotted. Nothing to worry about. “With each passing year, it seems less and less likely that he will reappear,” says J. Alan Pounds.
