Eared grebes in the Great Salt Lake
Salt Lake City — The first case of highly pathogenic avian influenza in wild birds in Utah during this current outbreak was confirmed in April 2022, and now the Utah Division of Wildlife Resources has confirmed the virus has been detected in birds in several new counties since November 2024.
The current outbreak of highly pathogenic avian influenza has been ongoing in the U.S. since 2022, but typically spreads more during the spring and fall bird migrations. In Utah, the virus has been confirmed in 16 counties since 2022, with the virus spreading to three new counties recently: Box Elder, Emery and San Juan.
"We saw a lull in new avian flu cases in wild birds from January 2024 to November 2024, but since last fall, we have seen another uptick in new cases across Utah," DWR Veterinarian Ginger Stout said.
Since November, 25 wild bird carcasses submitted for disease testing have been positive for avian influenza. The birds most impacted by the latest influx of avian flu cases have been geese (both snow and Canada geese), hawks, gulls, owls (both barn and great horned owls) and eared grebes. DWR biologists have confirmed that roughly 15,000 to 20,000 eared grebes have died along the Great Salt Lake, primarily due to avian influenza (although only a few carcasses were disease tested).
"Roughly 4 million eared grebes migrate through the Great Salt Lake each year, so the number that died from avian influenza should not have a significant impact on the overall population," DWR Great Salt Lake Ecosystem Program Manager John Luft said. "The salinity of the Great Salt Lake almost 'pickles' the carcasses, so they don't decompose or get scavenged like they would in a freshwater environment. The birds will likely continue to wash ashore in the coming months."
As of Feb. 10, 2025, 122 wild birds, one mountain lion, some skunks and three red foxes in Utah have tested positive for avian flu since 2022. The counties currently seeing positive avian flu cases in wild birds since November include:
- Box Elder
- Cache
- Carbon
- Davis
- Emery
- Millard
- Salt Lake
- San Juan
- Tooele
- Weber
Highly pathogenic avian influenza viruses are very contagious among wild birds and can cause rapid and high mortality in domestic birds, such as chickens, turkeys and domestic ducks. Typically, these viruses only occasionally kill wild birds, but this strain is more pathogenic and has been killing more wild birds.
The most common wild birds impacted by the virus are typically waterfowl, shorebirds, raptors and scavengers (which include birds like hawks, owls, ravens and vultures). There are usually few symptoms in waterfowl and shorebirds, but the virus can kill raptors and scavengers quickly. The virus is spread among birds through nasal and oral discharge, as well as fecal droppings. It can be spread to backyard poultry and domestic birds through contaminated shoes or vehicles.
Songbirds are not typically affected by avian flu, so people shouldn't have to remove their bird feeders unless they also have backyard chickens or domestic ducks, which are susceptible to the virus. However, if you have a bird feeder or birdbath, you should clean it regularly.
"The outbreak is still ongoing, so we are still advising anyone who finds a group of five or more dead waterfowl or shorebirds — or any individual dead scavengers or raptors — to report it to the nearest DWR office. Make sure you don't touch the birds or pick them up," Stout said. "Report it to us, and we will come collect them for testing. We are continuing to monitor this virus in wild bird populations. This particular strain is affecting more wild birds and is more widespread than the last outbreak of highly pathogenic avian influenza in the U.S."
The last outbreak of avian flu in the U.S. occurred in 2014-15, when highly pathogenic strains of avian influenza were detected in wild birds of the Pacific, Central and Mississippi flyways. During that outbreak, the virus was only detected in two healthy ducks in Utah.
For more information about the current avian flu outbreak in wild birds, visit the DWR website. You can also view all the latest cases of avian flu in wild animals on the DWR website. To report any symptoms of avian flu in domestic birds, contact the Utah Department of Agriculture and Food.
