NAHANT, Mass. — When coyotes approach children playing in the park, as they do with unnerving frequency in this tiny coastal town north of Boston, Kellie Frary springs into action, trying to drive the animals off while another adult quickly gathers Ms. Frary’s day care group.

“I don’t want to have to make that phone call, to tell a parent, ‘The coyote picked your kid,’” said Ms. Frary, a lifelong resident of Nahant, where 3,000 people inhabit one square mile.

No humans have been harmed by Nahant’s coyotes, estimated to number about a dozen. But after the disappearances of more than two dozen pets in roughly two years — and reports of three brazen, fatal attacks this year on leashed dogs accompanied by their owners — the town is ever more on edge. Its isolated geography — Nahant is essentially an island connected to the mainland by a narrow, 1.5-mile causeway — contributes to the sense of menace felt by some residents.

Compact, densely populated and surrounded by water, it is a hard place for coyotes to leave, and a hard place for them to remain mostly invisible to humans, as they often do in cities and more sprawling suburbs, wildlife experts said.

Earlier this month, Nahant’s three-member Board of Selectmen voted to enlist federal sharpshooters to track and kill some of the coyotes,making Nahant the first municipality in Massachusetts to seek the expert help through a new state partnership with the U.S. Department of Agriculture.

The plan has relieved many anxious residents, some of whom now carry whistles and baseball bats on strolls around town, and dress their dogs in $100 “coyote jackets” covered with metal spikes to repel attacks.

“I love animals, and I don’t want to see them killed, but some child on a porch is going to get taken,” said Lisa Wrenn, who watched a coyote snatch her 12-pound Chihuahua, Penelope, off a leash last summer as she stood on her front stairs. Left holding the leash and empty collar, she never saw the dog again, she said.

Though coyotes regard small pets as prey, attacks on people are rare and almost never fatal, according to coyote experts.

Support for the sharpshooting plan is not unanimous. Opponents have argued for a more humane approach, hoisting handmade “Save The Nahant Coyotes” signs near the causeway into town.

Francene Amari-Faulkner, a resident who has organized protests against the plan, said false claims and exaggeration have fueled hysteria and a rush to drastic measures. “If the town brings in sharpshooters, it’s going to be a bloodbath,” she said, “because then other towns will say, ‘We can do that too.’”

While a coyote problem on a peninsula jutting into the sea may be less than typical, human aversion to the species is well established. Coyotes have long been viewed as a nuisance, and millions have been poisoned, shot and trapped by frustrated or frightened humans trying to control their population.But their signature trait may be their persistence. By the 1950s, they had pushed east into Massachusetts; by 2000, they were present everywhere in the state except the islands of Nantucket and Martha’s Vineyard, according to the state Division of Fisheries and Wildlife.

Tony Barletta, Nahant’s town administrator, takes pains to remind residents there is no going back: Coyotes will remain, long after a handful are eliminated. And like it or not, residents will have to find a way to live alongside them.

“We fully expect to have them here in town,” Mr. Barletta said at a meeting of the Board of Selectmen last week. “Just because you’re afraid of coyotes doesn’t mean it’s a problem, and that’s a tough thing to explain to residents.”

Massachusetts offers fewer checks on the coyote population than many other places, with its abbreviated hunting season, local rules against discharging firearms, and ban on most effective traps, enacted by a ballot referendum in 1996.

In South Carolina, 25,000 to 30,000 coyotes are killed by hunting and trapping every year, while in Massachusetts, the annual total is around 500, said Dave Wattles, a biologist with the Massachusetts Division of Fisheries and Wildlife. Yet even in the South, he said, hunting has little impact on coyote numbers, known for rebounding rapidly from any dips.

As local encounters with the animals have multiplied — residents share videos of coyotes patrolling their porches on a Facebook page called “Nahant Coyote Victims” — theories have multiplied. Some locals believe the omnivorous creatures have wiped out all the island’s resident skunks and raccoons (rabbits have somehow persisted), and are hungrily stalking homes with pets, looking for food.

State and local authorities stress that attacks on off-leash pets are normal coyote behavior, unfortunate but not concerning. But in targeting dogs on leashes, coyotes in Nahant have deviated from normal patterns, indicating decreased fear of humans, Mr. Wattles said. Those attacks prompted the state to authorize the town to seek federal intervention to kill some animals.

Because there is no way for sharpshooters to identify the most aggressive, they will likely use trial and error, killing several and then waiting to see if atypical behaviors subside.

Experts say it will fall to the people of Nahant to re-instill a healthy fear of humans in the remaining coyotes — and that will require overcoming their own fear.

“If humans act submissive toward them, and run away, it teaches them they’re the king of Nahant,” Mr. Wattles said during an educational meeting hosted by the town for residents in July. “You have to teach them you’re a threat, and they’re not welcome.”

By engaging in ongoing harassment known as “hazing,” he said — chasing coyotes; spraying them with water; throwing sand or gravel at them; screaming and banging pots and pans to disrupt them — residents can re-establish boundaries.

But after seeing little impact from attempts at hazing, some residents worry it may be too late.

Michael Hanlon, a part-time resident of the town, said he “yelled bloody murder” and swung a three-foot stick at three coyotes who circled him and his dog Dewey on a residential street one recent night, but the animals only retreated a few feet.

Mr. Hanlon retreated into his house.

“They have no fear at all,” said Ms. Frary, the day care provider, whose 12-year-old Pekingese poodle, Brody, reluctantly dons a spiked vest on walks. “It’s like a teacher who was lenient, and then tries to be strict … They’re used to us now, and it’s too late.”

She said coyotes have been known to laze in the sun on the local golf course, watching players putt. Linda Tanfani, another resident, complained to town officials after loitering coyotes cast a pall over her game of pickleball.

“When they’re ruling over us, controlling our lives, it’s not right,” Ms. Tanfani said at the select board meeting. “I’m tense all the time.”

Wildlife experts say most coyote aggression toward humans stems from people providing the animals with food, which can drastically alter their behavior. In Arlington, a Boston suburb that saw three non-fatal coyote attacks on children in 2021, police later determined that a resident had been feeding a coyote. Officers killed the animal, and the town has had no problems since, a spokesman said.

A coyote attack can be so stealthy, it has been mistaken for something more mundane. John Malafronte, a driver for a clothing donation company, was standing in a parking lot in Swampscott, Mass. — across the bay from Nahant — early one morning in June, smoking a cigarette and texting on his phone, when he felt a pinch and reached to swat what he thought was a fly biting his leg.

When he glanced down and saw a coyote instead, “I flipped my lid,” said Mr. Malafronte, who suffered a puncture wound and later received rabies shots.

Stanley Gehrt, at the Chicago-based Urban Coyote Research Project, has studied coyotes for decades, tracking hundreds of them to learn how they live. He acknowledges that removing coyotes may be appropriate in some situations, but also reminds nervous suburbanites aboutthe coyote’s role in a healthy ecosystem.

Coyotes can help control populations of rodents, rabbits and Canada geese, Mr. Gehrt said; they also prey on white-tailed deer, which cause car accidents and endanger drivers.

Coyotes also offer humans a bracing dose of humility, he noted.

“We’ve done everything we can to wipe them off the continent for 150 years, and they’re moving into our backyards,” he said. “It’s a reminder that we don’t have control of everything.”