New Sonoma County bird flu cases affect more than 500,000 birds in biggest outbreak yet

Sonoma County has recorded its largest incidence of avian flu to date, with producers now forced to euthanize more than 500,000 birds at three local poultry facilities this week.

That brings the tally to seven sites and more than a million birds since the week of Thanksgiving, a widening trend that has sent a wave of dread through a $50 million county industry.

“Everybody’s kind of sitting with bated breath,” said Dayna Ghirardelli, executive director of the Sonoma County Farm Bureau. “They’re trying do all they can to protect their flocks, and crossing their fingers they can avoid an outbreak. No one feels immune to it. Everyone is on high alert.”

Highly Pathogenic Avian Influenza, known as HPAI, is a virulent virus, often carried by wild birds, that can prove devastating to bird populations at farms that produce eggs, chickens or ducks meant for human consumption. Since the start of 2022, almost 77 million farm-raised birds have been affected across 47 U.S. states.

California has been a hot spot, with a total of about 3.4 million dead birds, about a third of them in Sonoma County. Among states, only Ohio has recorded more, with about 4.5 million affected birds.

And the outbreaks are getting bigger in this state. Before Nov. 27, the largest California had seen was an incident that affected 162,000 turkeys at a commercial operation in Tuolumne County in August 2022. Since Thanksgiving, there have been seven California outbreaks larger than that, including a Merced County egg operation that had to put down 1.35 million birds a week ago.

Two of the recent local cases — both were confirmed by the U.S. Department of Agriculture on Monday — hit the Sunrise Farms brand, which has separate ownership groups among three Sonoma County facilities.

The larger of the two incidents recorded Monday was at Sunrise’s main facility on Liberty Road. It will result in the death of 497,700 birds. The other affected a private flock of 39,000 birds that supplies eggs to Sunrise for processing.

Tuesday, the USDA recorded another outbreak, at an unidentified commercial duck operation. That one will affect 3,500 birds.

Andrew Smith, the Sonoma County agricultural commissioner, said he wasn’t sure how disposal of dead animals was currently being handled, though he emphasized it would follow standards developed by the American Veterinary Medical Association.

“Standard operating procedure is to use a humane method of depopulation. And wherever possible, to compost on site,” Smith said. “If there are environmental constraints, for which there are adopted federal and state standards, you have to find an alternate form of disposal. Over the last few weeks, that has been through landfill. We are also currently researching the opportunity for composting off site.”

Sunrise Farms was also one of two producers that reported the first local outbreaks in late November, along with Reichardt Duck Farm.

“It will take a considerable amount of time dealing with this,” Michael Weber, a fourth-generation farmer and Sunrise co-owner, said Tuesday before hustling to meet with agricultural inspectors.

The timeline for that process might be hard to gauge.

“The question is how long it takes to rebuild a flock to the point where you’re producing the eggs you were producing before,” said Sonoma County Supervisor David Rabbitt, who represents the county’s poultry belt outside Petaluma. “It’s months and months of lost business. How you factor that in, the story is yet to be told.”

The economic loss to poultry farmers, as yet uncalculated, will be huge. That impact has already begun, Ghirardelli said, and not just to the farmers.

“We’re starting to see the fallout, with facilities needing to lay off employees,” she said. “And there are also ancillary effects, like grain companies. At this point, the rippling effect is starting to come to fruition. I hope we’re done with the outbreaks. But we’re gonna see a change in the market.”

Rabbitt said local feed suppliers are “worried sick.”

“They’re kind of outside the loop of any potential help that might come down,” he said. “So we’re trying to expand that as well. We’re trying to convey who is being harmed, and if there is matching up resources with folks who need it to keep their business going.”

And of course, there is the potential for sudden income loss among displaced poultry workers.

With all of that in mind, the Farm Bureau Foundation of Sonoma County has launched a Poultry Farms & Employee Relief Fund to assist those impacted by the outbreak.

“If you want a place to give back, please consider donating to FBFSC,” the Farm Bureau wrote in a Facebook post. “Your donation ensures that Sonoma County remains a diverse and thriving location for agriculture.”

Anyone interested in contributing can do so via the foundation’s fund site:

Since the initial wave of local infections in November, other outbreaks have been logged at an unidentified egg farm in southern Sonoma County (232,000 birds on Dec. 6), and at Liberty Ducks (4,900 birds on Dec. 7).

All of the identified local cases thus far are in the county’s poultry belt west of Petaluma. A number of egg, chicken and duck ranches are based there, including big producers like Perdue Farms and Petaluma Poultry. Weber has estimated about 1 million agricultural birds were being raised within a 5-mile radius of his farm.

Countywide, the tally is more than 2.6 million laying hens, pullets and broilers, according to the most recent Sonoma County crop report.

State, federal and local agricultural leaders have been on high alert throughout the outbreak, urging maximum biosecurity measures at poultry farms and even waiving requirements that certified organic operations must allow birds to go outside — now deemed unsafe, given the potential for infection.

The type of avian flu detected in Sonoma County and elsewhere in California is classified “high pathogen” because of its severity and infection rate among birds. The virus is carried primarily by waterfowl, including geese, which may transmit it along their migration routes. Many of those routes lead them to California and the Central Valley.

It is not easily transmitted to humans.

Federal and state food-safety protocols require that an entire flock be destroyed if a single case is detected.

So far, the response from state and federal agencies to Sonoma County’s outbreaks has been positive, Rabbitt said. He wants to ensure the county is a willing partner as well.

“As soon as it’s on your property, the clock is ticking and you want it off you’re property ASAP,” Rabbitt said of avian flu. “We just want to be sure we’re not the ones holding any things up. We’re working for them to have what they need. If we can exert any pressure or advocacy, we will.”

Staff Writer Mary Callahan contributed to this story. You can reach Phil Barber at 707-521-5263 or On Twitter @Skinny_Post.