How USGS Science Helps Manage Wildlife Disease: From Bat Fungus to Avian Influenza

The U.S. Geological Survey (USGS) is the federal government's main scientific responder to disease in wild animals — investigating die-offs, building tools to prevent and detect outbreaks, and backing the agencies that manage wildlife.

A USGS scientist uses UV light on a big brown bat (Eptesicus fuscus) to look for Pseudogymnoascus destructans, the fungus behind white-nose syndrome. Image from the USGS fact sheet on wildlife disease science

Investigating outbreaks

Through its Biological Threats and Invasive Species Research Program, USGS investigates causes of death in outbreaks among federal trust species — migratory birds, threatened and endangered species, fish that cross jurisdictions, marine mammals and other species of concern — and on Department of the Interior lands. These investigations often grow into research on how outbreaks spread and how to stop them, supporting the U.S. Fish and Wildlife Service (USFWS), the National Park Service, and state and Tribal agencies.

At the center is the USGS National Wildlife Health Center (NWHC):

• the only federal high-containment facility dedicated to wildlife disease surveillance and research;
• registered with CDC's Federal Select Agent Program and an affiliate of USDA's National Animal Health Laboratory Network;
• more than 40 years of work with federal, state and Tribal agencies on wildlife illness and death across the country;
• with the Canadian Wildlife Health Cooperative, the World Organisation for Animal Health's collaborating centre for wildlife pathogens, and a UN Food and Agriculture Organization reference centre for wildlife health.

Informing endangered species decisions

• Salamanders. USGS amphibian disease science underpinned a 2016 USFWS interim rule under the Lacey Act listing 201 salamander species as injurious — importing them could spread disease to native wildlife. The aim: keep out the invasive, deadly fungus Batrachochytrium salamandrivorans (Bsal).
• Bats. Data from the USGS-coordinated North American Bat Monitoring Program (NABat) showed the toll of white-nose syndrome, a fungal disease that eats away the bare skin of hibernating bats, wakes them too early, burns their winter fat and kills them. Three species under USFWS status review — the northern long-eared, little brown and tricolored bats — had declined by more than 90 percent.

Swabbing a boreal toad (Anaxyrus boreas boreas) to detect amphibian chytrid fungi. Image from the USGS fact sheet on wildlife disease science

Sylvatic plague, a non-native, flea-borne disease caused by Yersinia pestis, can kill people, pet cats and dogs, and wildlife; in 2015, several human cases were tied to exposures at Yosemite National Park. It also kills endangered black-footed ferrets and their prairie dog prey. USGS and partners developed an edible plague vaccine for prairie dogs; with fleas now resistant to deltamethrin dust, USGS is testing alternatives such as fipronil pellets. The plague vaccine became the basis for others — against white-nose syndrome, rabies in bats, and SARS-CoV-2 for black-footed ferrets.

USGS developed an oral vaccine to protect the endangered black-footed ferret (Mustela nigripes) from plague. Image from the USGS fact sheet on wildlife disease science

Leading the emergency response

Under Emergency Support Function #11 of the Federal Emergency Management Agency's National Response Framework, USGS is the lead federal agency for disease events in free-ranging fish and wildlife, including zoonotic disease outbreaks, during emergencies. It works with USDA, other Interior bureaus and the Department of Health and Human Services. After a presidential emergency declaration it can provide:

• wildlife emergency response teams;
• geospatial assessment and mapping;
• help identifying new and resurging zoonotic diseases;
• diagnostic labs, up to biosafety level 3 for microbes that can cause serious or fatal disease when inhaled;
• help to prevent, control and eradicate wildlife disease, and carcass disposal.

USGS has supported the national response to highly pathogenic avian influenza and SARS-CoV-2.

Proliferative kidney disease. In 2016, an outbreak of PKD on the upper Yellowstone River in Montana killed thousands of mountain whitefish, closed the river for weeks — unprecedented — and cost Park County alone about half a million dollars in business. With smaller outbreaks in 2017 and 2020, it exposed how little was known about the parasite (Tetracapsuloides bryosalmonae). USGS built lab and environmental DNA tests now used by USFWS and states, and is studying PKD in Montana, Wyoming, Idaho and California — partly with a robotic sample processor developed by the Monterey Bay Aquarium Research Institute.

Tracking specific diseases

USGS runs the WHISPers reporting system, where federal, state and Tribal wildlife health professionals share disease events, and feeds wildlife data to the Department of Homeland Security's National Biosurveillance Integration Center. Its capabilities also serve agriculture, for example on livestock pathogens shared with wildlife.

Avian influenza. With USDA, USGS works on diseases shared by wild and domestic animals — avian influenza, infectious salmon anemia, chronic wasting disease and rabbit hemorrhagic disease.

• USGS and USDA found the first HPAI cases in wild birds ahead of the 2015 U.S. poultry outbreaks.
• A 2021 webinar series prepared for the global HPAI outbreak reaching North America; USGS research then made the first 2022 detection of HPAI in a live wild bird.
• Avian influenza viruses can persist in Alaska and Minnesota wetlands for up to 7 months.
• USGS is building risk models of where wild birds and poultry meet.

USGS scientist Dr. Diann J. Prosser examining a ruddy shelduck (Tadorna ferruginea) in China, while studying movements of this migratory species, which was infected in the 2005 Qinghai Lake HPAI outbreak. Photo by John Y. Takekawa, U.S. Geological Survey

Elk. Deep snow in the greater Yellowstone ecosystem leaves little forage, made worse where fences and traffic break old migration routes, so elk are often fed pellets or hay in winter. Crowding at feedgrounds likely raises the spread of chronic wasting disease and brucellosis, cutting survival and growth. USGS is weighing alternatives for Wyoming feedgrounds with the National Elk Refuge and the U.S. Forest Service, and tracking elk with Global Positioning System collars to see how movement between herds affects disease risk.

Elk (Cervus elaphus) on a winter feedground in the western United States. Image from the USGS fact sheet on wildlife disease science

Avian malaria in Hawai'i. Caused by an invasive parasite (Plasmodium relictum) carried by invasive mosquitoes, it has driven steep declines in Hawaiian forest birds. USGS built a real-time avian malaria warning system so managers can factor climate into where they control mosquitoes.

The investment

USGS spends about $15 million a year on wildlife disease research — mostly at the NWHC, and through disease ecologists and veterinarians at other USGS science centers and Cooperative Research Units at land-grant universities — backed by modeling, statistics, decision science, human dimensions and economics research.

A symmetrical brain coral (Pseudodiploria strigosa) infected by stony coral tissue loss disease in April 2015 (left) was dead by April 2016 (right); USGS supports the National Oceanic and Atmospheric Administration's investigation of the disease. Photos by Ilsa B. Kuffner, U.S. Geological Survey

Sources

Based on U.S. Geological Survey Science to Support Wildlife Disease Management, by M. Hopkins and Suzanna Soileau, U.S. Geological Survey Fact Sheet 2023–3008; a work of the United States government in the public domain. The source's slips in two agency names ("Centers for Disease Prevention and Control," "Food and Agricultural Organization") are corrected.