Last September, a cappuccino-colored stray chicken appeared in Katherine Rae Mondo's neighborhood in Oakland, Calif. After it hung around the same intersection for a couple of days, Mondo took it in — her house had a coop, and she was already caring for a housemate's three-chicken flock.

She named the stray chicken Terribad, since, unlike most hens, "she was kind of a wild woman who didn't obey the rules, and she could fly," Mondo says.

It was easy to welcome another chicken, partly because Oakland's local policies for keeping poultry aren't that restrictive. Roosters aren't allowed, and hens just have to be housed at least 20 feet from any house. That's it. No rules about the number of birds, their coops, slaughter or care. Bare-bones local laws around chickens are really common, says Catherine Brinkley, a veterinarian and urban planner at the University of California, Davis.

Brinkley says these policies tend to focus on limiting nuisances, like early morning cock-a-doodle-dos or eyesore coops — leaving a gap in codes when it comes to health and safety. "They're not at all focused on public health considerations, like [requiring] training for new owners in washing hands and selling eggs, nor do they think about if somebody is hoarding chickens or other awful things that, quite honestly, happen with animal welfare," Brinkley says.

Healthy chicken, happy chicken

Brinkley has chickens herself — their names are Griffin, Hazel, Starlight and Bunnykissdoodoo — so she's well versed in the basics of chicken-keeping: The birds need food, water, space, predator protection and health care if they get sick. Hand-washing, and avoiding chicken smooches and snuggles, will protect people from picking up illnesses from chickens.

The backyard chicken trend isn't going away anytime soon — The Washington Post recently detailed the birds' growing role as icons of Silicon Valley. So Brinkley says it's worth remembering that chickens do carry some health risks.

The Centers for Disease Control and Prevention reported 1,120 cases of salmonella linked to backyard poultry between January and September 2017. Backyard birds bore the brunt of the blame for Egypt's Avian flu outbreak in 2014, and there's also the risk of spreading disease to commercial birds. Exotic Newcastle disease doesn't pose a major threat to most people, but outbreaks among birds in California have led to the euthanization of millions of commercial chickens at a time.

"That could be headed off at the pass if we made sure that we had good vaccine coverage, which is kind of the basic thing we do for cats and dogs for rabies," Brinkley says. Commercial chickens avoid many diseases with help from vaccines, she says.

Since those vaccines are sold in massive quantities for commercial farmers, they're often out of reach for chicken hobbyists, Brinkley says, who don't need thousands of doses. And there's another hurdle: taking fowl to the vet. "The other thing we do for cats and dogs is that you have to see your vet every year or every other year, and we don't have that stipulation for backyard birds," she says.

Brinkley is a veterinarian with plenty of agriculturally minded friends, so her birds get lots of medical advice. That's not the norm, though.

She recently studied backyard chicken policies in 100 cities in Colorado as a test case for understanding the codes that govern backyard birds, publishing her results in the Journal of Community Health. She found that only two cities required veterinary care for animals, and only "if deemed necessary."

But some cities — around a fifth of the places she looked at that allow chickens — did require owners to get a permit, which she says could make a big difference for chicken care. A few cities, including Fort Collins, Colo., routed their permits through the local Humane Society, to help give owners basic information on caring for their birds.

Greener urban pastures, with permits?

When Fort Collins moved to allow residents to keep chickens in 2008, it was a big deal. "I have never seen city council, or the community, more involved, than for chickens. It was standing-room only when the chicken ordinance was passed," says Bill Porter, the director of Animal Protection and Control for Larimer Humane Society, which serves Fort Collins.

Nowadays, when Fort Collins residents want backyard birds, they apply for a chicken license with the Larimer Humane Society, and the organization sends someone to inspect their chicken coop. "It just takes about 15 minutes to do it, to make sure all those points are covered for being responsible as a chicken owner, respecting the neighbors, addressing public health concerns. And also meeting the needs of chickens," Porter says.

Prospective poultry keepers pay a $30 fee to the Larimer Humane Society, and a chicken license allows up to eight birds for lots smaller than half an acre. Coops have to keep predators away from chickens, and slaughtering birds isn't allowed. Instead, owners have to take their chickens to a vet to be euthanized. Ideally, Brinkley says, this kind of permit would also loop in a requirement for routine vet visits, but it's a good start.

Stray chickens, like Mondo's Terribad, still show up in Fort Collins. But the permits sometimes provide clues about where birds belong, since chickens traveling on foot usually stay fairly close to home, Porter says.

In Oakland, would tighter policies dampen the thrill of having chickens? "I kind of love the chaos of it, I think it's really fun," Mondo says. "But i'm also all for regulations that would make animals safe and happy and well cared for."

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