Golden toad
Incilius periglenes (Savage, 1967)
The golden toad was a brilliant orange amphibian found only in a 10 km² patch of Costa Rican cloud forest, last seen on 15 May 1989 and declared extinct in 2004 — the first extinction widely attributed to climate change and the chytrid fungus pandemic.
Updated 25 July 2026
- Range
- About 10 km² of Monteverde cloud forest
- Male colour
- Uniform bright orange
- Female colour
- Dark with scarlet blotches edged in yellow
- Breeding adults counted 1987
- Over 1,500
- Last sighting
- A single male, 15 May 1989
- Declared extinct
- 2004 by the IUCN
The golden toad was almost implausibly bright — males a solid, glossy tangerine that looked painted rather than evolved. It lived in a single 10 km² patch of high-altitude cloud forest above Monteverde, Costa Rica, inside a protected reserve, and it was in no danger from logging, hunting or trade. In 1987 researchers counted over 1,500 breeding adults. In 1988 they found ten. In 1989 they found one. It has never been seen since. Nothing was cut down and nothing was killed: the species died inside its own protected reserve, which is what makes it the emblem of the global amphibian crisis.
Key facts at a glance
- The golden toad lived in roughly 10 km² of protected cloud forest and nowhere else on Earth — one of the smallest ranges of any vertebrate.
- Males and females looked so different that they were hard to recognise as the same species: males uniform orange, females dark with scarlet and yellow markings.
- Over 1,500 breeding adults were counted in 1987. Ten were found in 1988. One was found in 1989. None since.
- It is the first extinction widely attributed to climate change, and an early casualty of the chytrid fungus pandemic that has since affected over 500 amphibian species.
- Legal protection did not help. The species disappeared inside a reserve, from causes that reserve boundaries cannot stop.
- Chytrid fungus is now implicated in the decline of more than 500 amphibian species and the presumed extinction of around 90 — the most destructive wildlife disease ever recorded.
What killed the golden toad?
The best-supported explanation is a combination of disease and climate. Batrachochytrium dendrobatidis, the amphibian chytrid fungus, spread globally through the late twentieth century and attacks amphibian skin — which for amphibians is a respiratory and osmoregulatory organ, so infection causes cardiac arrest. Chytrid arrived in Central American cloud forests in this period and devastated amphibian communities. At the same time, warming sea surface temperatures were lifting the cloud base at Monteverde, reducing the mist that kept the forest floor permanently damp and drying the shallow pools the toads bred in. Drier conditions concentrated toads in fewer pools, which increased disease transmission, while also stressing animals in ways that reduce immune response. The 1987 breeding season fell in an exceptionally strong El Niño. The population that gathered to breed that year was the last one.
The amphibian extinction crisis
The golden toad is not an isolated case; it is the best-known member of the largest extinction event currently underway. Amphibians are the most threatened vertebrate class on Earth, with around 41% of assessed species threatened with extinction — against roughly 26% of mammals and 13% of birds. Chytrid fungus alone is implicated in declines across more than 500 species and the presumed extinction of around 90, making it the most destructive wildlife pathogen ever documented. The reason amphibians are so exposed is physiological: permeable skin that absorbs water and oxygen also absorbs pollutants and pathogens, and a life cycle split between water and land doubles the number of habitats that must remain intact. Amphibians are also the group that receives the least conservation funding relative to the threat, which is why the crisis proceeds with so little public attention.
Where it lived
A 10 km² area of the Monteverde Cloud Forest, Costa Rica
What caused it
- 1 Chytrid fungus (Batrachochytrium dendrobatidis)
- 2 Climate-driven changes to cloud forest moisture patterns
- 3 An extremely small range with nowhere to retreat to
What this extinction teaches
Protected status does not stop disease or climate. A reserve boundary cannot keep out a fungus or hold a cloud layer in place — which is why captive assurance colonies and disease surveillance now matter as much as land protection for amphibians.
Still here — for now
Still facing the same pressure: Glass frog
Central and South American cloud-forest amphibians directly in the chytrid fungus's path, several with ranges as small as the golden toad's and the same dependence on constant humidity. Captive assurance colonies and habitat protection are the only defences that exist.
IUCN status: Varies — several species Endangered or Critically Endangered
Did you know
The golden toad spent almost its entire life underground, emerging only for a few days each year to breed. Researchers who worked at Monteverde for years might see the species on fewer than a dozen days in total.