Chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis, has driven dozens of amphibian species to extinction and causes significant suffering in affected populations.
Chytridiomycosis causes a distinctive and distressing death in affected amphibians. As the fungus colonizes the skin, the animal becomes progressively unable to regulate its physiology, leading to muscle weakness, loss of righting reflex, and cardiac arrest. The prolonged nature of the death and its scale — affecting entire populations across mountainous regions — represents an immense welfare crisis alongside its conservation dimensions. Conservation programs that maintain healthy captive populations while attempting to develop biocontrol solutions serve both welfare and conservation goals, though the scale of the Bd crisis exceeds the capacity of ex-situ programs alone.