Healthy wildlife support ecosystem services that benefit Americans, including local economic profits from wildlife tourism and enduring cultural traditions like hunting and fishing. Healthy wildlife can also benefit human health. Studies show that wildlife‑focused activities, such as birdwatching, may ease anxiety and psychological distress even more than general nature walks. Simple activities—like being outdoors and observing wildlife—can reduce stress, lift your mood, sharpen focus, and lower blood pressure and heart rate. Healthy wildlife also help keep ecosystems balanced by controlling pests, pollinating plants, spreading seeds, and breaking down waste. Disruptions to wildlife population health can alert us to emerging threats like environmental pollution or diseases that can also threaten the health of people, pets, or livestock. 

USGS Wildlife Health Awareness Day launched in 2025 to highlight the actionable wildlife health science that the USGS provides to the nation. Through the Ecosystems Mission Area, the USGS is the leading federal agency for free-ranging wildlife disease research and surveillance. The USGS monitors the presence of pathogens and diseases in animals and the environment, develops tools for their detection, identifies whether environmental factors influence their spread, and studies the health risks that they pose. Our scientists are at the table with public and animal health agencies as they tackle diseases that affect mammals, fish, reptiles, and more, developing advanced tools for diagnosis, surveillance, risk assessment, and control.  

“Geese are a cosmic admonition to stop, look, and listen…. [and] an annual reminder of the community of the earth.” (Leopold, 1946)

Avian influenza, previously thought of as just a poultry disease, is reshaping wildlife health across North America, affecting not only wild birds but a growing number of wild mammals on land and in water. USGS surveillance of wild birds to detect avian influenza is critical to prevent widespread outbreaks across our ecosystems and protect our agricultural economy as well as public health. 

“If the deer like to go there, I thought, I had better take a look. I have often noticed that a deer's taste in scenery and solitudes is very much like my own.” (Leopold, 1953).

In recent decades, Chronic Wasting Disease (CWD) has grown from a little-known illness found in only a few populations of wild deer to a widespread disease that poses a serious threat to our ecosystems, including national parks, and local economies across large swaths of North America. The disease has now been detected in 36 states and five Canadian provinces and there is currently no cure or vaccine. The USGS is providing science to help managers better understand, track, and control CWD. 

“Once I knew a doctor who worked so hard that he had to start playing or cash his checks. He chose fishing as his hobby. One evening he became so absorbed in a trout pool that he fished until it was pitch dark, and he was amazed to find that even on a pitch black night a trout could consistently pick a black gnat from a brown hackle. He began to study, as a hobby, the optical structures and powers of fish. He is finding himself in a new field fairly bristling with miracles. He is learning things that only God knew before. But timid folks who stir up the dust on the beaten path merely think of him as a crank on fishing.” (Leopold, 1920).

Chinook (or King) salmon support numerous cultural and economic needs and make up more than 75% of the diet of many Indigenous communities. However, in recent years many adult salmon have died on their way to spawning grounds in the Yukon River, leading to commercial fishery resource disaster determinations by the Secretary of Commerce and an agreement between Alaska and Canada – for the first time ever – to ban Chinook fishing for seven years (one full life cycle of a salmon). USGS scientists are helping to understand how the parasite Ichthyophonus is contributing to this “en-route” mortality.

USGS Wildlife Diagnostic Capabilities

Learn more about wildlife diagnostic capabilities at the USGS:

Leopold, A. (1920). A man’s leisure time [Unpublished manuscript].

Leopold, A. (1946). The geese return [Unpublished manuscript draft].

Leopold, A. (1953). Round River: From the journals of Aldo Leopold (L. B. Leopold, Ed.). Oxford University Press.

Leopold, A. (1991). Conservation: In whole or in part? [1941]. S. L. Flader & J. B. Callicott (Eds.), The river of the mother of God and other essays (pp. 310-319). University of Wisconsin Press.