Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis, has driven more amphibian extinctions than any other infectious disease in recorded history. Individual frogs and salamanders experience significant welfare harms.
Amphibians dying from chytridiomycosis experience osmotic failure - a physiologically stressful death as their skin-based water regulation breaks down. The speed of population crashes means entire local populations can collapse within weeks of disease introduction. Whether frogs and salamanders experience suffering in a morally relevant way is uncertain, but the scale of mortality and the physiological nature of their deaths makes welfare consideration appropriate under precautionary principles. Probiotic treatments that reduce mortality and captive breeding programs that preserve species welfare for eventual reintroduction represent meaningful interventions.