SCARBOROUGH — New England cottontail rabbits like a mess. More precisely, these rabbits, which are endangered in the state of Maine, would like to hide out in a thicket of native (and edible) shrubs.

Which is why on a rainy Friday at the end of September, a dozen people were planting a mix of gray and silky dogwoods, willows, hazelnut, Virginia rose and other shrubs in a corner of the Rachel Carson National Wildlife Refuge; they hope if they build just the right habitat, the remaining bunnies who make their home in this 30-acre marshy patch of the refuge will make it through another season. And ideally, raise a family or two.

Efforts to save the once prolific species, now numbered in mere hundreds, are focused on restoring habitat and, increasingly, on a pilot project to supplement the remaining rabbit population by releasing New England cottontails bred in captivity. Lou Perrotti, director of conservation programs at Roger Williams Park Zoo, oversees the breeding program at the zoo. “I’ve got a bunch coming your way tomorrow,” he said Wednesday.

These cottontails were headed to locations in Cape Elizabeth and Wells, according to Cory Stearns, a biologist with Maine’s Department of Inland Fisheries and Wildlife. They are not the first captive-bred rabbits to be released in Maine. The last effort, in 2017, didn’t go well: Most of the 18 New England cottontails brought into the state died. But high mortality rates are typical, said Wally Jakubas, a mammal scientist with the state’s Department of Inland Fishers and Wildlife who oversees the regional recovery work. Jakubas said a total of 30 rabbits will be released in two of the strongholds for the species, Wells and Cape Elizabeth, in the coming weeks.

Workers move into Libby Field, federally owned land in Scarborough that is home to a multiyear project to transform a 25-acre block of the property into shrubland – the type of habitat that is most suitable for cottontail rabbits.

But now another threat is on the horizon, or rather, the border – a non-native and apparently more durable species, the Eastern cottontail, which is already pushing out the native cottontails in other parts of New England.

THE MISADVENTURES BEGIN

New England cottontails are one of only two species of rabbits native to Maine (the snowshoe hare is the other). For centuries, the cottontails were a vital part of Maine’s ecosystem, dispersing seeds and providing food for prey species such as bobcats, coyotes and hawks, not to mention early settlers. Their numbers began to decline around the region in the 1950s, less than four decades after Massachusetts-born conservationist Thornton Burgess made them iconic and adored with the publication of his “The Adventures of Peter Cottontail.”

Commercial and governmental development, including the construction of Interstate 95, is the most obvious culprit. Mankind’s preference for lawns and forests over messy thickets is another factor.

“People either want nice open fields, or they want forests,” said Jeff Tash, the wildlife biologist and the New England cottontail habitat restoration coordinator, gesturing around the meadow, which was thick with goldenrod and grasses, but not a lot of the kind of year-round cover the rabbits require. The cottontails want something more “in between,” he said.

No one knows how many of the endangered rabbits are still tucked into this particular pocket of Scarborough. Linda Cullivan, who lives adjacent to the portion of the refuge where planting was happening, said in an email that she and her husband, Mike, have spotted cottontails in the yard, under their deck and also on their patio. They even had one in their garage once. They last saw one this spring, probably in March, she recalls.

Of the dozen volunteers and staffers from the refuge and the U.S. Fish & Wildlife Service, only a few have seen the rabbits in the wild. Sean Campbell, the greenhouse manager who had transported 2,500 young shrubs – cultivated in a hoop house at the refuge, from both seeds and cuttings – in pots to the field for the two-day planting event, was the winner with three sightings. “That’s not fair,” said Alexa Duschesneau, who had organized the volunteer event and was in the middle of planting a hazelnut bush.

She was joking, at least a little. Duschesneau is a relative newcomer to the regional coalition working to save the New England cottontail – she’s been working with the refuge since January. She’d expected that her best chance to see the rabbits would be in the winter, when volunteers go on the annual count, traversing snowy fields looking for rabbit scat on the snow, and maybe even the brown rabbits themselves.

But the cottontails are elusive. Even Tash hasn’t seen many. He pulls out his phone to show a couple of slightly blurry photos of a cottontail he spotted in the refuge; you have to move fast to get a camera out, because the bunnies are gone in an instant.

It falls to Tash and his team to respond to reports of sightings around Maine – about 5 to 10 a year, maybe 15 tops, he said. “We go and investigate and we never find them,” Tash said.

Researchers believe 400 to 500 New England cottontails survive in Maine, just a slight rebound from the crisis point that led to their being declared endangered in the state in the first place, as they are in New Hampshire.

Shannon Matzke, a botany intern with the U.S. Fish & WIldlife Service, hops on a shovel as volunteers Marlie Perkins, left, and Breilly Roy plant shrubs to create habitat suitable for cottontails at Libby Field in Scarborough.

Spurred by research into the species in the 1990s by John Litvaitis, now a professor emeritus of wildlife ecology at the University of New Hampshire’s Department of Natural Resources & the Environment, Maine wildlife officials started counting cottontails.

They realized how dangerously close the once commonplace species was to disappearing altogether – as it has in Vermont – and in 2004 Maine closed the hunting season on them entirely. “We came up with an estimate of 300 some rabbits,” Jakubas said. “That was a real shocker. It stopped everyone in their tracks. People said, ‘Man, we shouldn’t be hunting these things.’ ”

Maine listed the rabbits as endangered in 2006, and that same year, the New England cottontails became candidates for being listed under the federal Endangered Species Act.

Since then biologists and refuge managers around New England and New York have been working on ways to improve the outlook for the small, brown bunnies (the snowshoe hare is also brown, but it turns white in the winter, has longer ears, and is bigger). Overall, conservation efforts have been successful enough that the rabbits were removed from potential federal listing in 2015.

But in Maine, the recovery has been limited, and that state endangered status holds. In the early part of the 20th century, the New England cottontail ranged as far north as Penobscot Bay and inland to Augusta, biologists say. Now the native cottontails’ population has been reduced to the coastal region between Cape Elizabeth and Kittery, with about a half-dozen focal areas, including the Berwicks, Kittery, York and its stronghold, Cape Elizabeth. “But they’re isolated from each other,” Jakubus said. And despite the ban on hunting, their numbers haven’t rebounded.

“We have to think of ways to help these populations,” Jakubus said.

AN ISLAND HOME

Very early on in the recovery effort, Jakubus said, biologists captured New England cottontails who were living near the Portland Jetport. “Fifteen rabbits or so,” he said. They moved them to Stage Island off of Cape Porpoise. “I thought we were moving them out to Shangri-la,” Jakubus said. “You can smell the roses from the island from like a quarter mile away.”

But the rabbits behaved oddly on Stage Island. They sunned themselves out in the open, never a good idea for a something an avian predator is highly interested in. From their tracks, it was clear they were hopping down the beach. “Out of cover!” Jakubus said. They were too friendly to human visitors. And they failed to mate, possibly because they were related. Genetic inbreeding is becoming a big problem for the rabbits that remain, Jakubus said.

In a year, they were all gone. Some suspect a long-tailed weasel.

But in Rhode Island, efforts to move cottontails to Patience Island have been successful. Why the difference? No one knows for sure, but one likely factor is that at Patience Island, biologists started with more rabbits, said Lou Perrotti, who runs the breeding program at Roger Williams Park Zoo. “With Patience, we really saturated it. In the beginning years, all of the rabbits went on to Patience.”

The other factor? Perfect cottontail habitat. “It is just god-awful out there,” Perrotti said. “Everything is either poison ivy or has thorns or spikes.”

Bri Benvenuti, a biological technician for the U.S. Fish & Wildlife Service, plants a grapevine.

New England cottontails continue to be mysterious, even to those breeding them in captivity. “Sometimes the more we know the less we know,” Perrotti said.

Some females are good breeders, producing litters of between four and six, he said. Others not so much. Even in captivity, there is about a 50 percent mortality among the young. In the wild, Perrotti said, imagine the weasel or feral cat who comes upon a nest – the litter can be gone in an instant.

As Roger Williams Park Zoo fine-tunes the breeding process, they hope to eventually get up to four litters out of the captive rabbits a year. Right now it’s two to three. The more litters the better.

“Remember a rabbit’s ecological role. They are a prey species. They breed like they breed because they die like they die,” Perrotti said.

NEW MAINERS

Despite the high mortality rates, last year’s release of 18 rabbits wasn’t a failure. Jakubus said. Even in good scenarios in the wild, a 60 percent mortality rate among adults would be common, he said. One of the females released almost made it to breeding season, and Jakubus believes one or two males from last year’s release group are out there, somewhere.

Linda Cullivan, who lives adjacent to where the planting was taking place in Scarborough, said she and her husband, Mike, have spotted cottontails in their yard, under their deck and also on their patio.

The hope, said Jeff Tash, is those males mixed in – mated even – with the local population. When biologists and volunteers head out in the winter snows, looking for signs of the cottontail, they’ll collect the rabbit’s feces and ship it to New Hampshire for analysis at a lab at UNH. Testing will determine if DNA from the rabbits bred in captivity has entered the native population.

Though researchers and volunteers remain optimistic about the re-populating project, that optimism is tempered for reasons that include competition from another kind of rabbit, the Eastern cottontail, native to areas west of the Hudson River. Because the Eastern cottontail has better eyesight – making it less vulnerable to hawks and other predators – it does better in open areas than the New England cottontail. Likely introduced through hunting clubs, the Eastern cottontail is spreading throughout New England. In Rhode Island, outside the gates of the zoo where the New England Cottontails are being bred, the native rabbits have been all but pushed out by the Eastern cottontail.

In 2017, the first Eastern cottontails showed up in Maine, on Badgers Island in Kittery, indicating the species is nosing its way across the border, i.e. the Piscataqua River. Literally. Officials put cameras on the Maine and New Hampshire side of the Memorial Bridge. “To try to see if we could get evidence of whether the rabbits were using this bridge,” Jakubas said. “We got pictures of a lot of rabbits standing on the Portsmouth side.”

In this story of conservation and hope, the invaders with the better eyesight, who don’t require a thicket to hide in, would be the fierce bad rabbits.

BE VERY QUIET

The New England cottontails are on the march as well, however, their travels are assisted by humans. This year, Roger Williams Park Zoo has had the most successful breeding year yet, with 77 cottontails tagged and microchipped, then released in New Hampshire, Maine and on Patience Island. To acclimate to the outdoors, the rabbits first spend a few weeks at a penned 2- to 3-acre facility at Great Bay National Wildlife Refuge in New Hampshire.

The partnership has been quiet about the project to bring in rabbits from outside the state, in part because it doesn’t want to get the public’s hopes up. The reality is, if you let a species dwindle to 300, rebounding isn’t easy, even when the will is there.

“We have been asked by a lot of different people, ‘When we will see them? When will you bring us rabbits?’ ” said Kate O’Brien, wildlife biologist at the Rachel Carson National Wildlife Refuge. “The story is that rabbits are not doing well in Maine.”

A cold winter could wipe out a population living in a less than ideal location. They need the green growth to eat in the spring, summer and fall and then the woody material from the young forest – another term for the thicket – to make it through the winter.

“We just need them in the right spot,” O’Brien added.

A few yards away, the crew of volunteers digging were doing their best to turn a field in Scarborough into a tangle that would be just that. If the cottontails did not thrive here, at least 15 different species of birds would, as well as the pollinators.

Mary Pols can be contacted at 791-6456 or at:

mpols@pressherald.com

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