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:

Cooperative Research

Blackrock: Biological Hotspot and Hotbed of Collaboration — Fort Collins Science Center

Amphibian Disease — Northern Rocky Mountains Science Center

Disease — Amphibian Research and Monitoring (ARMI)

  • News

  • ARMI conducts national survey for salamander chytrid fungus

    In 2016 ARMI and National Wildlife Health Center scientists conducted a nationwide sampling effort to detect the salamander chytrid fungus Batrachochytrium salamandrivorans (Bsal). Bsal is native to Asia where indigenous salamanders carry the fungus without disease symptoms. However, Bsal has been spread through human facilitation to Europe where it has been implicated in major population die-offs of wild salamanders...

  • Promising Tools Assess Presence of Chytrid Fungus in Amphibian Habitats

    Amphibians, including threatened and endangered species like the Oregon Spotted Frog, may benefit from a recent study that highlights the use of promising tools...

Podcasts and Interviews

Wisconsin Scientists Help Discover Another Deadly Frog Disease

Wisconsin scientists have documented another disease that's killing North American frogs. A team led by the United States Geological Survey's National Wildlife Health Center in Madison has found severe Perkinsea infections, or SPI, killed a sizable number of frogs in 43 states over a 16-year period.

Listen to the interview

Advancing ARMI: In search of Chytrid Fungus

In this episode, we follow a group of students from the Jane Goodall Environmental Middle School on a class trip to Pintail Marsh at the Ankeny National Wildlife Refuge. There they join USGS ecologist Tara Chestnut to investigate and sample for the amphibian chytrid fungus. Join us, as we explore how research and wonder can bring greater light to this potentially fatal fungus, only in this episode of the USGS Oregon Science Podcast.

Fatal Frog Fungus

The potentially lethal fungal disease chytridiomycosis has been associated with declining amphibian populations around the globe. This rapidly emerging disease, and the chytrid fungus that causes it, have forced scientists to scramble to learn more. There are still plenty of mysteries about the origin and spread of the fungus. With today's episode we will shed some light on what we know and what we can expect for the future of amphibians. Join us as we interview USGS ecologists Mike Adams and Tara Chestnut, as well as USGS hydrologist Chauncey Anderson.

  • Publications

  • Pathogenic lineage of Perkinsea associated with mass mortality of frogs across the United States

    Emerging infectious diseases such as chytridiomycosis and ranavirus infections are important contributors to the worldwide decline of amphibian populations. We reviewed data on 247 anuran mortality events in 43 States of the United States from 1999–2015  

    Nature, August 2017

  • Using decision analysis to support proactive management of emerging infectious wildlife diseases

    Despite calls for improved responses to emerging infectious diseases in wildlife, management is seldom considered until a disease has been detected in affected populations. Reactive approaches may limit the potential for control and increase total response costs  

    Frontiers in Ecology and the Environment, April 2017

  • Early action to address an emerging wildlife disease

    A deadly fungal pathogen, Batrachochytrium salamandrivorans (Bsal) that affects amphibian skin was discovered during a die-off of European fire salamanders (Salamandra salamandra) in 2014. This pathogen has the potential to worsen already severe worldwide amphibian declines.  

    USGS Fact Sheet 2017-3013, February 2017

  • A Framework for Modeling Emerging Diseases to Inform Management

    The rapid emergence and reemergence of zoonotic diseases requires the ability to rapidly evaluate and implement optimal management decisions. Actions to control or mitigate the effects of emerging pathogens are commonly delayed because of uncertainty in the estimates and the predicted outcomes of the control  

    Emerging Infectious Diseases, January 2017