Vanishing in silence: The salamander crisis that no one is talking about
They may be small, elusive and easy to overlook, but salamanders play an outsized role in the health of ecosystems. As ‘indicator species’, their presence – or absence – signals the health of their habitats. But across Europe, these amphibians are now in crisis, facing a deadly threat: a fungus introduced via the global pet trade.
Amphibians are the most threatened group of vertebrates in the world, and international trade plays a major role in their decline. Over 98% of traded species are not subject to international regulation, and the movement of animals often occurs with minimal oversight or biosecurity. This creates ideal conditions for the spread of pathogens, including emerging fungal diseases.
One of the most alarming examples occurred in 2010, when European scientists identified a previously unknown chytrid fungus that was devastating native salamander populations: Batrachochytrium salamandrivorans, or Bsal. The fungus originated in East Asia, where amphibian species co-evolved with the pathogen and developed natural resistance. However, through the international amphibian trade, the fungus has been inadvertently introduced into Europe, where native species lack such resistance.
European invasion
First identified in the Netherlands following a 96% collapse in local fire salamander populations, Bsal has since been detected in Belgium, Germany and in captive collections in the UK and Spain. In susceptible species such as the fire salamander, infection causes severe skin lesions and is often fatal.
The fungus spreads easily through infected animals, especially those released into the wild or kept in poor conditions. Captive breeding centres, wildlife markets and informal trade networks continue to serve as hubs for disease transmission. Once introduced, Bsal can survive in moist environments such as water and soil and be carried by animals that show no signs of disease, making eradication extremely difficult.
Global Risk
Although Bsal has not yet been detected in the wild outside of Asia and Europe, scientists warn of the threat it poses to North America, home to the greatest diversity of salamanders in the world. The United States alone is home to more than 190 species, many of which are already threatened by habitat loss and climate change.
If Bsal were to become established in North American ecosystems, the consequences could be catastrophic. Modelling suggests that more than 80 species in the US and more than 140 across the continent could be at risk, particularly in biodiversity hotspots such as the Appalachians and the Pacific Northwest.
What Needs to Happen
Experts are clear: prevention is the only viable strategy. Once Bsal is established in wild populations, eradication is unlikely.
Urgent action is needed, including:
- Tighter trade rules, including mandatory Bsal-free certification for imported animals.
- Harmonised surveillance and detection protocols across the EU and globally.
- Public awareness campaigns to prevent intentional release and promote responsible pet ownership.
- Increased biosecurity in zoos, breeding facilities and field research.
- Investment in research on thermal tolerance, treatment and species susceptibility.
EU Member States have started to implement passive surveillance, but coordination and funding remain uneven. A harmonised European response – supported by enforcement and stakeholder engagement – is needed.
More Than Just Disease
The crisis facing salamanders is not just about Bsal. These amphibians are also under pressure from climate change, pollution and habitat degradation. Wetlands are being drained, forests are being fragmented and water systems are being polluted – all increasing the vulnerability of already stressed populations.
Protecting salamanders is about more than saving a single group of animals. It’s about protecting the delicate ecological balance they help maintain – controlling insect populations, recycling nutrients and signalling the health of their environment.
At a time when biodiversity loss is accelerating and zoonotic diseases are on the rise, paying attention to the fate of salamanders isn’t just environmental prudence – it’s a necessity.
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