NOMANS LAND — The 38-foot aluminum catamaran sliced across a light chop on Vineyard Sound, headed for a sandy brown strip of land with a foreboding name and a treacherous past.
Closed to the public, Nomans Land, 3 miles southwest of Martha’s Vineyard, is littered with unexploded bombs and rockets from its years as a naval bombing site.
This week, the federal government was delivering a payload of a gentler sort: 13 cinnamon-colored New England cottontail rabbits, each one nestled in its own compartment in wooden boxes stowed behind the captain’s chair.
The US Fish and Wildlife Service, which had outfitted the rabbits with tiny GPS collars, was on a mission to help rescue the species by establishing a self-sustaining colony on Nomans Land, a 628-acre federal wildlife refuge.
The release of the rabbits was the culmination of a monthslong effort, which required trapping the rabbits, testing their DNA, and scouting for a suitable site, all to give the delicate bunnies their best shot at survival.
“We made it!” exclaimed Eileen McGourty, a Fish and Wildlife Service biologist, when the catamaran landed on Nomans Land, greeted by a herd of gray seals lolling on the beach.
Unlike its cousin, the hardy Eastern cottontail, which has been ravaging gardens across the region, the New England cottontail is a sensitive type, requiring thickets and shrubbery for food and protection.
Yet that low vegetation has been gradually disappearing, either cleared for housing or allowed to mature into fully grown forest. Hastening the rabbits’ decline has been the resurgence of predators such as foxes and coyotes.
The Fish and Wildlife Service had listed the New England cottontail as a candidate for the Endangered Species list in 2006 but removed it from consideration in 2015 following intense efforts to breed the rabbits in captivity, establish another colony on Patience Island off Rhode Island, and preserve their habitats.
But “we really haven’t been able to turn the tide,” said T.J. McGreevy Jr., a research assistant professor at the University of Rhode Island, who has spent a decade studying the species.
Officials plan to bring more cottontails to Nomans Land over the next several years in hopes of establishing a colony of 600 rabbits. That reserve could then be used to replenish populations on the mainland, if they continue to decline.
“We need backup,” McGreevy said.
Officials said the island should be a cottontail Shangri-la: it has no mammalian predators and its windswept hills are covered with brambly sumac and bayberry, perfect territory for the promiscuous rabbits to reproduce and nibble green leaves and shoots.
The project began in February when John Garofoli, a technician at the Massachusetts Department of Fish and Game, used apple slices to lure the rabbits into traps in Mashpee and Barnstable.
From there, the rabbits were taken to Roger Williams Park Zoo in Providence, where veterinarians removed tiny pieces of flesh from their ears for DNA testing to confirm they were New England cottontails and not Eastern cottontails, which look nearly identical.
To get the rabbits healthy enough for their relocation, they were given medication to remove fleas and worms, Garofoli said.
Students at Bristol County Agricultural High School in Dighton then cared for the bunnies over the last several months.
On Tuesday — launch day — the rabbits, which shriek when frightened, rode quietly from Falmouth Harbor to Nomans Land in the back of the Fish and Wildlife Service’s catamaran.
“They can’t ask, ‘Are we there yet?’ So that works out for us,” Garofoli said.
When the boat landed on the beach, Fish and Wildlife staff carried the boxes onto the sand and through the shrubbery to a spot about three-quarters of a mile inland.
The workers said they weren’t worried about stepping on a bomb because most have been cleared by the Navy, which transferred control of the island to the Fish and Wildlife Service in 1998.
“We’ve been coming here for years — and we’re still here,” said Stephanie Koch, a Fish and Wildlife biologist.
Garofoli and McGourty knelt in the grass to open the first compartment on the first box.
But the pioneering bunny huddled inside, refusing to venture out as a TV camera, two photographers, a radio reporter, and a documentary film crew crowded around in anticipation.
“Seems he’s a little bit shy,” McGourty said.
Garofoli used a gloved hand to coax the rabbit out and, once it was clear of the box, it leaped like a flash into the bush.
“So there goes our first colonist,” Garofoli said.
One by one, the rabbits — five females and eight males — were released, each one scampering away more eagerly than the first.
“They’re like, ‘Let us out of here now,’ ” McGourty said. “They’re ready for it.”
Once all 13 rabbits had been freed, the wildlife officials pumped their fists in the air and whooped in celebration.
Five officials remained behind to camp overnight. They planned to set up base stations to receive data from the rabbits’ GPS collars and ensure the system was working. Over the next several months, biologists plan to track the rabbits’ movements and monitor how many survive.
Sounding a bit rueful, McGourty acknowledged she may not see any of the rabbits again, given their propensity to hide and because the GPS collars only give a general sense of their location. But she said she believes the bunnies are on to bigger and better things.
“They look like they belong here,” McGourty said, as she headed down a grassy path to gather her camping gear for the night.