WARE, Mass. >> To biologist Tom French, the 3.5-mile uninhabited island was a conservationist’s dream. Where better, he thought, to bring a locally endangered species so it could thrive far from existential threats like car tires or humans?

The species in question, though, was a venomous snake, and French’s plan set off a cascade of anger and a clash between science and politics. Petitions piled up. Worried constituents emailed videos of swimming snakes to state legislators. The objections became so vociferous that lawmakers held an oversight hearing, where Massachusetts’ top environmental official apologized and promised to convene a committee that could at least consider other options.

The plan’s sinuous path has confounded French, assistant director of the state Division of Fisheries and Wildlife’s Natural Heritage and Endangered Species Program.

“I’ve got a pretty thick skin, but this one is unique,” French said in an interview before the hearing on May 10, which went on for more than four hours. He added, “It disappoints me that people don’t think more highly of our native species.”

The uproar is over the timber rattlesnake — Latin name, Crotalus horridus — which is large, ranges from yellowish to black, and has a plangent rattle and a supply of venom that it primarily uses to snare prey for feeding. The species lives throughout the eastern United States, but its population has dwindled in New England, where the creatures live in colonies, hunkered in deep dens to survive cold winters.

Centuries of hunting and human development that encroached on forested land have left the species exceedingly rare in New England. In Massachusetts, conservationists estimate there are fewer than 200 timber rattlers left, in five colonies.

French has an unusual proposal: Seed a new colony of snakes on an uninhabited island called Mount Zion in the middle of the Quabbin Reservoir, in the center of the state.

The island is prime snake real estate, with a boulder field, forested habitat and exposed bedrock for basking. The plan would most likely place fewer than 10 snakes there every year, beginning no sooner than next spring. The snakes would have trackers inside them so scientists could follow their movements.

“The whole point of this project,” French said, “was to find a place we could protect rattlesnakes from people.”

But neighbors are more worried about protecting people from rattlesnakes.

“Instead of ‘Snakes on a Plane,’ it’d be snakes on an island,” said Charles Comeau, an engineer who lives in Ware, which borders the reservoir, referring to the 2006 action film. “It would definitely make you think twice about where you step, where you walk into the woods.”

A major problem for many locals is that the island is not exactly an island — it is, in fact, connected to the mainland by causeways and another island. Snakes also happen to be excellent swimmers.

“All it takes is two of ‘em to get across, and then all of a sudden you got snakes all throughout the town of Ware,” said Kyle Whitcomb, a police officer in Ware who was fishing in a pond near the reservoir on a day off earlier this year. He added, “I’m petrified of snakes.”

The fears are largely unfounded. Deaths from timber rattlesnakes are rare; in the unusual event that they bite a human, they do not always use venom, and if they do, there are antidotes. But last year, a Pennsylvania man who was highly allergic died after being bitten by a rattlesnake.

Perhaps more significantly, many people do not like snakes, rating them in polls as more frightening than public speaking, heights or needles. The debate highlights the difficulty of protecting unpopular species.

“Snakes really inspire emotional responses, and they have a bad reputation, even though they’re virtually harmless if you’re paying attention to where you put your hands and feet,” said David A. Steen, an assistant research professor at Auburn University in Alabama, who is trying to reintroduce the indigo snake to part of that state. “Putting rattlesnakes on an island is kind of a compromise.”

French has said repeatedly, at public hearings and in the news media, that the rattlesnakes would be unlikely to leave the island, which is full of food. And they would die if they did not return to their dens, he said. A state fact sheet said the last recorded human fatality from a rattlesnake in Massachusetts was in 1791.

But no one is listening, French said.

“I can show you the scientific journal article. I can say it over and over,” he said. “And people will say, ‘Sorry, I just don’t believe you.’”

This has left French in a quandary.

“I can hear somebody’s concern, and I can empathize with it,” he said. “But if I know the concern is a false worry, I don’t quite know what to do with it.”

The plan has drawn support from conservationists and some local nature groups, but state lawmakers have gotten an earful from worried citizens.

“People are scared of snakes,” said state Sen. Eric P. Lesser, a Democrat, who this week filed legislation to put a one-year moratorium on the plan. “Our responsibility is to soberly separate that out and say, OK, what’s driven by irrational fears and sort of rational concern about an animal that does pose fears because it’s poisonous?”

Gov. Charlie Baker, a Republican, said this week that the plan was “on pause,” but that, to his own surprise, he was standing up for the species.

“I can’t believe here I am, defending snakes,” Baker said during an interview on a Boston Herald radio program. “I don’t like snakes either, OK? I’m not a snake guy. But they absolutely have a role to play in nature.”

One aspect of the plan is already underway — 100 miles away from the Quabbin, in a windowless room at the Roger Williams Park Zoo in Providence, Rhode Island.

There, one morning this month, baby snake No. 600093, coiled in its plastic bin, flicked its tongue, unaware of the furor over its future. It is one of five timber rattlesnakes that have been bred for the island.

“If we only conserve the cute and the cuddly,” said Lou Perrotti, the zoo’s director of conservation, “we’re going to have forests full of butterflies and bunny rabbits, and they’re going to be very nonfunctioning ecosystems that would eventually collapse.”

“A lot of us very passionate biologists,” Perrotti added, “we’re going to save the snake.”

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