SALT LAKE CITY — Biologists with the Division of Wildlife Resources are now estimating that more than 50,000 birds have died along the south arm of the Great Salt Lake during the latest influx of avian influenza.
Officials with the division say that multiple waves of influenza have affected Utah's wild bird populations. The virus has again been detected in wild birds around the Great Salt Lake and several other counties throughout Utah.
According to the Utah Division of Wildlife Resources, the current outbreak of avian influenza has been ongoing since 2022, but the disease typically spreads more during the spring and fall bird migrations.
“We saw a lull in new avian flu cases in wild birds from March 2025 to September 2025, but in the last few months, we have seen another uptick in new cases across Utah,” DWR Veterinarian Ginger Stout said.
Since October, 49 wild bird carcasses have been collected from across Utah and submitted for disease testing and have tested positive for avian influenza. The birds most impacted by the latest influx of cases are:
- Eared grebes in Box Elder, Davis, Salt Lake, Tooele, and Weber counties
- California gulls in Salt Lake County
- Canada geese in Box Elder, Cache, Davis, Iron, Sevier, Salt Lake, Summit, Utah, Washington, and Weber counties
- Ducks in Box Elder and Davis counties
- Great horned owls in Box Elder, Davis, Summit, and Weber counties
- Hawks in Box Elder, Davis, and Weber counties
- Swans in Cache and Salt Lake counties
- Turkey vultures in Box Elder and Weber counties
While biologists estimate that roughly 50,000 eared grebes and 250 California gulls have died along the south arm of the Great Salt Lake during this latest influx, only a few carcasses were disease tested.
“Roughly 4 million eared grebes migrate through the Great Salt Lake each year, so the birds lost to avian influenza in this recent wave should not have a significant impact on the overall population,” DWR Great Salt Lake Ecosystem Program Wildlife Biologist John Neill said.
Since 2022, 242 wild birds, one mountain lion, some skunks, and three red foxes have tested positive for avian flu in Utah. The virus has been confirmed in 19 counties in Utah since 2022.
Experts say the most common wild birds impacted by the virus are typically waterfowl, shorebirds, raptors and scavengers. It can be spread to backyard poultry and domestic birds through contaminated shoes or vehicles.
Officials say people with bird feeders are not at a heightened risk due to songbirds rarely being affected. People shouldn't remove their bird feeders unless they also have backyard chickens, domestic ducks, or wild waterfowl on their property.
Those with bird baths and feeders are advised to clean them regularly.
