Cadillac Mountain's base is about 2 degrees Celsius warmer than the summit. That approximates the temperature models suggest will be common at the top in 50 years.
The landscape is bathed in orange Aug. 3, 2022, as the sun rises and filters through a cloud on Cadillac Mountain in Acadia National Park. Credit: Courtesy of Aislinn Sarnacki

On a perfect summer day at the summit of Acadia’s Cadillac Mountain, throngs of tourists took in the expansive view of rocky ledges, surrounding hills and the Gulf of Maine.

But Chris Nadeau was focused on the tiny plants at his feet, shooting up from thin soil between the granite that covers much of the mountain top. Just a few inches tall, with small white flowers, it was a three-toothed cinquefoil.

“It’s a plant that’s been identified to be really sensitive to climate change,” Nadeau said.

This story is part of Maine Public’s series “Climate Driven: A deep dive into Maine’s response, one county at a time.”

Nadeau, the climate change adaptation scientist at the nearby Schoodic Institute, said scientists have done modeling to assess the plant’s future as temperatures rise.

“They predict that the plant will lose 98 percent of its distribution in Maine because of the increased temperatures,” Nadeau said. “So it’s a really good subject for understanding how can we make a population more resilient to climate change. How do we stop that 98 percent loss throughout Maine?”

On that day, Nadeau was checking on three experimental plots on Cadillac: One at the summit, another partway down the mountain and a third at the base, which is about 2 degrees Celsius warmer than the summit. That’s important, because it roughly approximates the temperature that models suggest will be found at the summit in 50 years.

Nadeau’s work is related to assisted migration, which simply means physically moving plants and animals to locations that might suit them in a changing climate.

But Nadeau is looking at an even finer point — he’s wondering whether certain varieties of the same species might be better designed for warming temperatures. And he covered a lot of ground last year to find his subjects.

“I hiked over 60 miles, up over 15,000 feet,” Nadeau said. “I visited 31 different locations throughout New England, ranging from Gloucester, Massachusetts, north to Borestone Mountain in central Maine, and I collected 100 plants from each one of those locations.”

He then planted these cinquefoils in an experimental plot on the Schoodic peninsula, and the three plots on Cadillac. The goal is to see if samples of the same species from other locations respond differently to the local conditions.

Nadeau wondered if increasing the genetic diversity of the cinquefoil, and relocating specimens that might already be adapted to warmer climates, could one day help cinquefoil to thrive in the warmer temperatures.

Abe Miller-Rushing, the science coordinator at Acadia National Park, said that Cadillac Mountain is a perfect place to do this type of study, because it has such dramatically different climates at its base and summit.

“It’s great that with a 10-minute drive, you can go 50 years into the future, climate-wise,” Miller-Rushing said. “And so that gives you the opportunity to test out a lot of different things and learn a lot of different things about how plants will respond to future climate conditions.”

And in the interest of public education, he said Cadillac’s popularity also puts thousands of visitors in proximity to scientific research.

“We’ve found that visitors are really interested in understanding the science that’s going on here,” he said, “and also really interested in understanding the actions that we’re taking to protect our natural and cultural resources.”

Back on the summit near Nadeau’s test site, tourist Kelly Schoeller was visiting from Wisconsin. She was glad to hear about the climate research, which she said is a good reminder of the more pedestrian aspects of conservation, such as the park’s project to restore the plants on Cadillac that have been trampled underfoot.

“It’s very important that people respect that you can not go off these trails, you can not walk on the vegetation,” she said. “That, sure your photo shoot is important, but we’ve all got to respect, and stay on the trails, and make sure we’re not disrupting anything.”

Nearby, Nadeau was checking the growth of his plants. Surprisingly, he wasn’t yet seen many differences between the samples gathered from different locations.

“And there might not be any differences,” he said. “And that’s the whole point of the study. People have proposed that this should work, this is a climate change adaptation strategy that should work, and people are implementing this strategy all around the world, with all sorts of different species. But maybe it doesn’t work. And that’s the role of science is to test these things.”

And he said that in addition to serving as a research station, Cadillac will play another significant role as the climate changes.

“Even though it is going to warm up here during climate change, it might not become too warm for a lot of the unique species up here,” Nadeau said. “And that makes it a climate change refugia, a place where species might be able to persist, despite, 2, 3, 4, 5 degrees Celsius of warming.

That means there’s a decent chance that three-toothed cinquefoil will still be here in 50 years, as future tourists stroll the summit.

This article appears through a media partnership with Maine Public.