Mount Desert Island is a rare place on the Atlantic coast where mountains rise directly above the ocean, their pink granite shoulders studded with glacial kettle ponds. In between the peaks, the island’s many gorges are crowded with vertiginous white pines and aromatic spruces. For over a century, the beauty of this spot, far up the Maine coast, has given it a reputation as a paradisiacal escape from cities like New York and Boston. Its principal town, Bar Harbor, was originally named Eden. It’s no wonder that Mount Desert Island hosts the Northeast’s sole national park: Acadia.

In January 2024, a pair of nor’easters detonated Acadia’s aura of untouchable remoteness when they battered the island with hurricane-force winds. A storm surge of over 15 feet drowned shoreside paths across the eastern edge of Mount Desert Island and eroded much of its only sandy beach at the same time the formidable waves tossed massive stone steps into a hillside, causing it to partially collapse. On the other side of the fjord that cleaves the island in two, picnic areas and campgrounds were transformed into thickets of fallen timber by the punishing wind. A particularly vulnerable state highway that crosses a natural breakwater known as Seawall fractured, its asphalt slabbing off as the rocks underneath were drawn back out to the Gulf of Maine—a body of water that has warmed by more than 2°F in just the past 30 years, three times faster than the global average.

Walking Seawall Road a few months after the storms, I was struck by the quiet. With the breakwater still closed to vehicles, I could hear the soft swell of rocks being tugged by the waves and the occasional crack of a seagull opening a mussel by dropping it on a boulder. Nature’s reassertion of its own rhythms over the hurly-burly of humanity was not to last: By midsummer, the road was back open, as were practically all of Acadia’s trails and the rest of the infrastructure serving a stream of tourists. With about 4 million visitors a year, Acadia is as popular as Yosemite and Rocky Mountain National Parks.

After a 2021 flood destroyed a bridge on the Maple Spring Trail, it was replaced with a sturdier structure to withstand future floods.

The combination of Acadia’s vulnerability to the rising sea and its rank among the most visited national parks in the country have made it a laboratory for a policy that the National Park Service adopted in 2021 to confront the climate crisis on federally managed lands nationwide. The Resist-Accept-Direct (RAD) framework is named for the three broad strategies that resource managers are being encouraged to use to either rehabilitate damaged park facilities or prepare them for anticipated changes brought on by spiking temperatures, ecosystem destabilization, and coastal erosion. Managing land this way goes hand in hand with President Joe Biden’s 2021 policy order that seeks to rectify the federal government’s chronic disregard for the continent’s original inhabitants. For Acadia, that means decisions about how to prepare Mount Desert Island for its tumultuous future must be made in consultation with the Wabanaki, a confederacy of the four federally recognized nations whose ancestors have lived in what is now Maine since the last ice age: the Mi’kmaq, Maliseet, Passamaquoddy, and Penobscot.

The combination of the RAD framework and Biden’s 2021 order represents a seismic shift in the National Park Service’s approach to conservation. Rather than managing toward some fictional past when the landscape existed without any people on it, superintendents such as Acadia’s Kevin Schneider are learning from the Indigenous history of the land they oversee as they plan for a warming world. Acadia has become a leader in this transition—in part through its partnership with the Schoodic Institute, a nonprofit research center—by both initiating one of the nation’s first RAD processes and stepping out of the way so the Wabanaki can harvest culturally significant sweetgrass from the park’s wetlands.

Acadia’s vulnerability to the rising sea and its rank among the most visited national parks in the country have made it a laboratory.

Over the course of the summer, as tourists swarmed across Mount Desert Island on infrastructure that sometimes looked as if it were being held together by painter’s tape, I sought out the Schoodic Institute’s researchers to understand what putting both western science and Indigenous knowledge into action toward the same goal really entailed. “These spaces were stewarded by Native people for centuries,” said Suzanne Greenlaw, a Schoodic Institute ecologist and a member of the Houlton Band of Maliseet Indians. “Often the biodiversity that people value was there because of Indigenous value systems.” Greenlaw’s work in the Bass Harbor Marsh, one of the few completely un-developed portions of Acadia, illustrates how Indigenous traditions can help fortify fragile ecosystems.

Another ecologist at Schoodic, Chris Nadeau, is working to rewild the summits of Acadia’s highest mountains, where decades of careless footfalls have killed much of the natural groundcover. This work also represents a form of climate adaptation, since the pace of anticipated warming is forcing a more propulsive approach to research than might be found elsewhere. “If we’re going to be doing a management action, like restoration, we should be doing it in such a way that we can learn,” Nadeau said. “Instead of just implementing one strategy and then monitoring it for a decade, let’s implement two or three or four strategies at the same time.”

Acadia is hardly the only national park taking action as it contends with warming-fueled catastrophes. In Montana, Glacier National Park has been experimenting with moving its native bull trout to colder waters for the past decade, and it also had to deal with a major flooding event in 2022. In California, Joshua Tree National Park is warming faster than its iconic namesake is capable of migrating; yet helping Joshua trees reestablish themselves in more favorable climes is not nearly as pressing a concern as preventing wildfires like the one that killed 1.3 million of the expressive yuccas in 2020.

New growth appears in an experimental garden near the Penobscot Mountain summit.

What makes Acadia’s efforts so notable is how sweeping the reorientation around climate adaptation has been over just the past three years. Still, when I walked the closed Seawall Road, listening to the waves and breathing the mist, I couldn’t help reflecting on the strain these reforms were adding to the fundamental tension between the National Park Service’s two missions: conservation and recreation. Over the course of the summer, that tension felt like it was rising by the month. For all the noble work being done by Schoodic scientists and Acadia’s rangers, it was impossible to ignore how pressure from tourists and locals alike was forcing them to shy away from the hard choices that will be necessary for Mount Desert Island to survive the 21st century.

REACHING THE TRANQUILITY of Bass Harbor Marsh from the frantic hustle of Bar Harbor—where cruise ship passengers crowd into fudge shops while locals glower and honk—requires driving past towering Cadillac Mountain and glassy Eagle Lake, then over the drumlins the Laurentide ice sheet left behind 17,000 years ago. That glacier cut deep grooves into Acadia’s ancient peaks, leaving an impression on the face of the island like the scratches of a monumental bear claw. The shallower divots are filled with lakes. The deepest created Somes Sound, which bifurcates Mount Desert Island.

Once you’ve crossed the sound, you reach the Quiet Side, where only the most ambitious tourists stray. The road then winds past a state highway that traces a Wabanaki footpath and another pinched glacial lake before reaching Marshall Brook. That marsh-lined waterway gradually widens into Bass Harbor, an anchorage at the island’s southwesternmost extremity where most of the boats belong to lobstermen, not sightseers.

Walking through the National Park Service land that surrounds the brook, I followed a deer path through a dense thicket of aster and highbush blueberry, swatting at pervasive mosquitoes while my boots sucked mud. The path terminated on a thin granite shelf serving as a barrier between the inlet’s salty water and all the plant life an unusually high tide could drown. It was above that shelf that I noticed a stand of sweetgrass, its lithe tips bowing in the breeze.

Sweetgrass is used in Wabanaki ceremonies and to adorn traditional ash-wood baskets. The plant mostly grows in intermediary tidal zones, and much of it could vanish as sea levels continue to rise. (Meanwhile, inland ash trees are imperiled by the invasive emerald ash borer, which is chewing its way ever deeper into Maine’s forests—another dire sign of rising temperatures.) Even in the short term, sweetgrass has become extremely difficult for many Wabanaki to access because practically all of Maine’s coast is either privately owned or managed by the government. The award-winning Passamaquoddy basket maker Jeremy Frey told me about a spot at Roque Bluffs, just up the coast from Mount Desert Island. “We used to harvest there, my whole life,” Frey said. “Then one day, some man came and said we can’t cross his land to get to it. We’re literally picking blades of grass! He just couldn’t handle it.”

New growth appears in an experimental garden near the Penobscot Mountain summit.

Such confrontations stem from white settlers infringing on Wabanaki lifeways as far back as the 18th century, when Mount Desert Island—known as Pesamkuk in the Wabanaki language—first began attracting outsiders traveling up the coast. The island had been a summer fishing destination for the Wabanaki for centuries by that point. Long before settlers established Bar Harbor in 1763, the Wabanaki knew the spot as moneskatik (“clam-digging place”). Their Indigenous ancestors left behind large collections of shell fragments and cooking tools across the island. These shell middens date back at least 3,000 years, not long—in geologic terms—after the withdrawal of the ice sheet.

The first tourists on the island were the Northeastern industrialists who rebranded themselves as “rusticators” in the late 19th century. By 1912, the State of Maine criminalized spearfishing—a cultural practice many Wabanaki still relied on to catch salmon—and 11 years later, the town of Bar Harbor outlawed the camp where many basket makers lived during the summer months. This effectively sequestered them to the mainland, even as state lawmakers refused to acknowledge their existence. The federal government did not officially recognize any of the Wabanaki tribes until the 1970s. Then in 1980, Congress forced the establishment of a handful of small reservations for each tribe, one of which Frey grew up in.

The Biden administration charged the National Park Service with integrating Indigenous nations into its management decisions in 2021, but many Wabanaki had already been calling for the restoration of their ability to harvest sweetgrass within Acadia for years by that time. Greenlaw, the Maliseet ecologist, bolstered that campaign in 2023. She published a study showing that patches of Bass Harbor sweetgrass that had been harvested by Wabanaki volunteers regrew so quickly that within two years their stalks outnumbered those in control patches left untouched. Traditional harvesting led to healthier sweetgrass, which could strengthen the salt marsh—a crucial buffer zone between land and sea that can resiliently absorb and redistribute seawater. Salt marshes are one of the most endangered ecosystems in the world because of widespread coastal development. This goes as far back as the 18th century, when settlers transformed salt marshes into grazing pastures, and continues to this day with the building of private homes. Without these marshes, however, everything inland is more vulnerable to storm surges.

Volunteers for Friends of Acadia and the Schoodic Institute on Hemlock Bridge.

In July 2024, Acadia completed an environmental assessment stating that sweetgrass gathering would not pose a threat to any park resources. The practice fell under the Resist heading of the RAD framework, given that it would fortify an imperiled wetland ecosystem. 

Since the turn of the 20th century, conservation has revolved around the premise that human impacts are inherently damaging to ecosystems. Only once Greenlaw and her colleagues—informed by Indigenous tradition—used Western science to prove the value-add of a practice like sweetgrass gathering were park rangers willing to accept that removing plant life does not necessarily cause harm. Indigenous peoples have had this type of symbiotic relationship with their homelands throughout history. “If you’re valuing Indigenous knowledge,” Greenlaw said, “then you should also value Indigenous people as conservationists and scientists themselves who can decide and self-determine what is care in a landscape.”

From that perspective, an artist like Frey can play just as valuable a role in helping Acadia face the rising tide as any ecologist. “I haven’t really scoured the national park for fields like Suzanne has,” he said, “but if there’s good grass there, it’s a wonderful thing. Just to comfortably walk in without worrying about anybody, just go have a nice day and pick some of your medicine.”

TOWERING ABOVE the busy side of Mount Desert Island, Cadillac Mountain is the tallest peak on the Eastern Seaboard. The most strenuous path to the summit is a vertical climb from the east, which entails passage through three distinct biomes. The mossy realm of beech and elm gives way to a hardier spruce forest up until the summit, where the trees fall behind entirely and the burnished leaves of lowbush blueberry sprout between granite boulders. Alternatively, you can hike the ridgeline, passing through these zones at a more leisurely pace. That trail intersects with the most popular option: a paved switchback with a near constant stream of jacked-up trucks, teetering SUVs, crisp Teslas, and roaring motorcycles that delivers roughly 2 million people to the mountaintop parking lots every year (four out of five summitters arrive this way).

Increasingly volatile storms are damaging Mount Desert Island. In January 2024, a nor’easter sent chunks of Seawall Road into the Atlantic.

No matter how you get to the top, the panoramic vistas from Cadillac are spectacular: The smaller mountains on every side cascade down into the North Atlantic, which glitters in the spread between the Schoodic Peninsula and Blue Hill Bay. That such an overlook is reachable regardless of physical ability makes the road vital. But such access also invites that annual crush of tourists, whose boots and sneakers—not some natural process—have left much of the summit bare.

When distracted visitors tread on low-lying plants, the plants die, leaving behind dirt that quickly erodes, exposing raw granite. Acadia has roped off portions of the summit to prevent further deterioration of its vegetation since the 1990s, but more recent efforts to restore plants to the top of Cadillac are also contending with anticipated warming across the park. After all, there’s no sense in reestablishing vegetation if it’ll simply wither away as Maine’s once mild summers turn hot.

Chris Nadeau is Schoodic’s climate change adaptation scientist. After meeting at the top of Cadillac in June, we strained to make ourselves heard over a blaring car alarm on the short walk from the parking lot down to one of his restoration plots. He indicated the patch of soil, held in place by sandbags and covered in a decaying coconut-fiber burlap out of which a few delicate white flowers were sprouting. “This is the Accept approach,” Nadeau said, putting the summit restoration project in RAD terms. “We just put the soil down; whatever comes, comes. We’ll live with it.” It had been seeded not by researchers but by the natural reproduction cycle of the plants still clinging to the summit.

Elsewhere, Nadeau was trying more of a Direct method. I followed his lead past an overlook where tourists were staging a picnic, then through a hedge of alder and goldenrod to a raised bed that was subdivided into squares, most of them full of a short plant with deep-green leaves. “This is called three-toothed cinquefoil,” Nadeau said, squatting down and clasping the distinctive, triple-pronged edge of each little leaf between his fingers.

The plant is adapted to cold, boreal climates, and average winter temperatures are rising twice as fast as average summer temperatures in Maine. According to one estimate, the state is poised to lose 98 percent of its cinquefoil by 2100. The absence of cinquefoil could be disastrous for the highly trafficked summit of Cadillac because the plant’s netlike root system plays an outsize role in stabilizing the restoration plots Nadeau is overseeing. “That leaves us in a really weird spot,” he said. “We’ve got this plant doing really well now, and we want it to be doing really well going forward.”

One potential solution is a novel process known as assisted gene flow, a type of human-assisted evolution. The hope is that cinquefoil preadapted to anticipated climate conditions will transmit its beneficial genes to other cinquefoil to help more of the plants survive. Nadeau had set up raised beds where cinquefoil from 31 warmer New England summits could crossbreed with the local variety and had replicated these beds at the summit and base of Cadillac, which is 3.6°F warmer than the top (a proxy for the summit’s temperature trajectory). “We’re directing the gene flow toward the future,” Nadeau said.

Since the experiment began in 2021, the genotypes from warmer summits around New England didn’t seem to be doing any better at the base of Cadillac than the cooler-acclimated local genotypes—basically everything planted there had died. Nadeau remained coolheaded about those early results, estimating he’d need at least five years to work out the kinks in the experiment before it would be possible to determine if assisted gene flow was worth pursuing at scale. Given the urgent need to preserve the ecosystems on Acadia’s peaks, that meant the Accept approach to summit restoration was taking center stage. Nadeau gestured from the parking lot toward two other mountains, Penobscot and Sargent, as he described his efforts to restore their summits, enlisting volunteers from a group called Friends of Acadia to haul soil up to the top.

MAPLE SPRING TRAIL is among the oldest trails in the entire national park system. It was built in 1871, a year before the establishment of Yellowstone. That history was obvious on a damp July morning when I sauntered along the lichen-spotted bog walk that provides passage over the marshy earth at the base of Sargent Mountain, the trail’s half-round logs cutting a rugged curve through a grove of eastern white pines. Once through the swamp, I started uphill via an exquisite staircase of stone, its steps the handiwork of the Depression-era Civilian Conservation Corps.

All of a sudden, the pines and hemlocks parted and I found myself staring at a bridge built from freshly cut timber. Rather than the aged gray of the rest of the woodwork on the trail, this bridge was auburn and formed a fresh stream crossing. While the original path leading up to the bridge had been packed firm by decade after decade of footsteps, on the other side of the newfangled bridge, the treadway was all pink gravel, only just beginning to sink into the earth. This path was also notably higher—in some places, it had been jacked five feet above the stream bank by bales of hay wrapped in plastic netting.

The contrasting infrastructure was a clear sign of how much management of Acadia has already shifted in response to climate change. Looking at the streambed, I immediately understood why the trail renovation had been necessary. There, marooned chunks of lumber and hip-high boulders attested to the flood that had destroyed much of Maple Spring Trail in 2021. That June, more than five inches of rain fell on Sargent Mountain in the space of just three hours. It was evidence that coastal Maine’s storms are becoming more ferocious, a message that was hammered home by the winter of 2024. Though more localized, the damage from the 2021 flooding was still enormously destructive. The stream became a torrent that uprooted stone steps, realigned the riverbank, and tore a bridge off its pilings. “Maple Spring just got completely wiped out,” Super-intendent Schneider said, comparing the event to “a flash flood in a canyon in the West.”

Rather than just rebuilding all the old infrastructure and hoping for the best, Schneider had embraced the chance to test out the RAD framework. Over the course of the next two years, Acadia’s rangers worked with Friends of Acadia and the Schoodic Institute to come up with an all-of-the-above approach to rehabbing Maple Spring Trail. Replacing the destroyed bridge with the taller, more robust structure that startled me on my hike was necessary to maintain the trail and resist future floods; moving part of the trail upslope was a way to accept that future floods are likely; and reinforcing the stream bank to keep water from easily cresting it served to direct future floods away from the path.

“We wanted to sort of exercise that muscle of the RAD framework,” Schneider said. “Much like a soccer team does drills before they play the game, right?” As anticipated, RAD has come to inform management decisions throughout Acadia in the years since. The new policy allowing for Wabanaki basket makers to gather sweetgrass in the park promises to be a similar sort of pilot program that rangers can build from, proving the value and sustainability of including Indigenous knowledge in their work. Once that happens, the stage will be set for Wabanaki voices to be included in other RAD-informed projects, such as the ongoing summit restoration work.

Bringing together many perspectives inevitably leads to tension. Greenlaw is particularly wary of publicizing when and where sweetgrass is harvested. “We’re really concerned about the idea of fetishizing Native practices,” she said, describing emails that some visitors have sent to park officials, asking to watch Wabanaki harvesters at work. “This spotlight has woken up some non-Native people to want to engage with this practice in a way that is not comfortable for a lot of people.”

Even more acute is the intense debate about coastal infrastructure that last year’s winter storms triggered. While park officials quickly rebuilt popular amenities in the busiest areas of Acadia, they had no jurisdiction over Seawall Road, the state highway that passes over a breakwater on the Quiet Side, leaving it up to the Maine Department of Transportation to decide if a road that routinely floods was worth rebuilding.

Two hundred locals packed into an elementary school for a public hearing about Seawall in June. The owner of a lobster pound—a seaside shack through which tides flow to keep freshly caught lobsters alive—threatened legal action against the state if it didn’t reopen the road. In response, a MaineDOT official argued the state’s position that maintaining Seawall Road indefinitely was unrealistic. “Things are changing,” the official told the crowd. “Was last winter a fluke? I don’t know.” Nevertheless, the state eventually went along with local demands, and Seawall reopened to traffic a few weeks later. Quiet Siders celebrated and got back to their usual routine, the sounds of their engines drowning out the waves.

“We’re not living in a time of stability,” Schneider said when I sat down with him at his office in Acadia’s Conservation Corps–era headquarters, a building resembling a log cabin that blends nicely into the surrounding woods. Schneider’s easygoing demeanor matched the low-key environment, but that didn’t mean he wasn’t concerned for the park. I asked how it was possible to measure progress toward adapting Acadia for the future given that new challenges seemed to be emerging more quickly than restoration efforts could proceed. He answered with an alarming scenario: the inevitable closure of Thunder Hole. Located on the eastern edge of the island, Thunder Hole is a natural cleave in the granite shoreline that forces waves into a dramatic splash, exploding with foam and an overwhelming crack of sound. In the hours leading up to high tide, tourists crowd along the safety rails above Thunder Hole, taking pictures and giggling with delight when they’re soaked by the icy water of the North Atlantic.

“A place like Thunder Hole is sort of iconic,” Schneider said. But because of its high exposure, the landmark took a direct hit during the January storms, leading to the destruction of about a hundred yards of the shoreline path that provides visitor access. That path was rebuilt ahead of the busy season, but given the certainty that more storms will be hitting the park more regularly, Schneider asked, “At what point with Thunder Hole do we say we’re not going to do it anymore? We can’t provide that walkway, that access, because it just doesn’t make sense from an investment standpoint.”

Schneider’s hope is that if he keeps talking persistently about climate change’s impact on Acadia, both regular visitors and lifelong Mainers will gradually come around to the idea that the island they have known and loved for so many decades is changing irrevocably—and quickly. Based on the scene at the elementary school in June, it was clear to me that most of Mount Desert Island was still in more of a Resist mindset than an Accept one. Schneider couldn’t help wondering, “At what point does that change?”