How the chytrid fungus pandemic is devastating global amphibian populations and the welfare implications of disease-driven declines.
Chytrid-infected amphibians experience a disease process causing electrolyte imbalance, heart failure, and death that constitutes significant welfare harm at both individual and population scales. The mass die-offs documented in previously abundant species represent both conservation catastrophes and welfare emergencies. Individual welfare in affected wild populations is difficult to address at scale, but captive assurance colony programs protect both genetic diversity and individual animals from disease. Probiotic treatments represent a welfare-positive intervention that could scale to wild populations if delivery methods can be developed. The primary prevention challenge is reducing pathogen spread through trade regulation and biosecurity for amphibians moving internationally.