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Amphibian Diseases

Amphibians are the most threatened groups of animals on the planet. Diseases (e.g., chytrid fungi, ranavirus, severe perkinsea infections (SPI)) are negatively impacting these species.

Chytrid fungus (Batrachochytrium dendrobatidis, Bd) was identified 15 years ago as one of the primary causes of death for many amphibians. However, the ecology and epidemiology of Bd is still being investigated. A second type of chytrid fungus (Batrachochytrium salamandrivorans, Bsal) is emerging in Europe. While Bsal primarily affects salamanders, frogs can also become infected and spread this disease. SPI has been associated with large-scale frog die-offs in at least 10 states.

USGS formed the Amphibian Research and Monitoring Initiative (ARMI) to lead a cooperative national effort that is monitoring amphibians and researching potential causes of decline, including disease.

USGS is proactively responding to the threat of Bsal: