Napa County’s review of rodent bait stations in the airport industrial area found violations that do not warrant penalties and no evidence that toxins are harming wildlife, though officials said that is a legitimate concern.
Changes take place following the investigation requested by the citizen. The county, which conducts 250 to 300 pesticide-use field inspections annually, has announced it will do more to ensure already-placed rodent bait stations comply with state law.
In addition, the county will increase outreach and education with pest control companies. This will include looking at best practices and promoting non-chemical rodent control methods.
“This investigation has given us the opportunity to look at this particular issue in a different way,” said Tracy Cleveland, county agriculture commissioner.
Resident Yvonne Baginski and the Napa Sierra Club asked the county to investigate the matter early this year. Baginski noticed small metal bait stations by the dozens around warehouses in the southern industrial area near a creek and wetlands.
She fears hawks and other wildlife could die after eating rodents poisoned by the bait stations.
The county Agricultural Commissioner’s office inspected 380 bait stations on 388 hectares in the airport industrial area and found that about 100 had such problems that they were improperly marked. It found 60 abandoned and empty stations. This required businesses to fix the problems.
Inspectors found no evidence of wildlife being killed by eating poisoned rodents. The California Department of Fish and Wildlife has not reported any recent non-target wildlife poisonings from Napa County, according to the recently released investigative report.
The investigation did not link poisoned bait stations with any decline in falcon population. Given factors such as habitat loss and drought, a study by a state or federal agency would likely be needed to prove any correlation, the report said.
Baginski said that these findings do not mean that secondary poisonings do not occur. To prove a case of poisoning, a carcass must be necropsied by the state Department of Fish and Wildlife. Most people who find a carcass don’t report it. Birds also fly far from where they may have been poisoned, she said.
She reported a dead hawk on Orchard Avenue north of the city of Napa to Fish and Wildlife, Baginski said.
“I have no idea if they went out, or if they did and the hawk was gone or whatever,” she said. “How would we ever know how it died?”
Businesses that involve food are required by federal law to control pests at their facilities. The most common chemical control method used is rodenticide-treated bait, and the practice is likely to continue for the foreseeable future, the state Agriculture Commissioner’s Office report said.
In the Ecosystem Protection Act of 2020, California restricted the use of certain rodenticides linked to harm to mountain lions, owls and other wildlife. These “second-generation anticoagulant rodenticides” are largely banned, although they may be used in certain settings involving food.
The county found two sites using these toxins and both fell under the exemption. Most pest control companies no longer use these toxins, the county report said.
Still, the risk of accidental wildlife poisoning is a legitimate concern, the county’s investigative report said.
A Senate analysis for the Ecosystem Protection Act of 2020 said the same. A statewide ban on certain toxins is expected to reduce wildlife exposure, it said.
“However, the importance of appropriate tools for vector control (including rodents) should not be dismissed, particularly in urban environments where conditions may support rodent proliferations and associated disease outbreaks,” the state Senate’s bill analysis said.
The Napa Sierra Club appreciates the county’s agreement to conduct more rodenticide use inspections and take appropriate compliance/enforcement actions, the group said in a statement to the Napa Valley Register.
“The (report) on the investigation showed that we were right to be concerned about the way traps are distributed, labeled and maintained,” the Sierra Club said in an email.
These traps remain legal if used in ways that comply with state law. But Baginski said filing a complaint with the county’s Agriculture Commissioner’s office had an effect.
“I think it raised awareness,” Baginski said. “No one ever brought any of this to their attention.”
She said an alternative to using bait stations for rats is snap traps.
Baginski likes to walk on a path along Sheehy Creek in the airport industrial area. She sees wildlife such as herons, beavers and wild turkeys. She also sees the warehouses and the bait stations.
“The problem is that these bait stations are placed in wildlife areas,” Baginski said. “These are traditional wildlife areas.”