Understanding the effects of climate change on fall foliage is critical for regions like Down East Maine relying on fall tourism.
Hikers work their way up the Beehive in Acadia National Park in early October 2022. Credit: Esta Pratt-Kielley / Maine Public

It was a beautiful early October day at Pigeon Hill Preserve in Steuben as a group got ready for a fall foliage hike organized by the Downeast Coastal Conservancy. Despite the Maine foliage report saying the state was not quite at peak, the colors looked spectacular.

“I think it’s like just about peak. Not quite there, not fully … but we’re starting to lose a couple leaves, so pretty good,” said Cathy Lookabaugh, the membership and outreach director for the Downeast Coastal Conservancy.

That day’s hike was a group of locals who’ve come to leaf peep, like Barbara Snapp, who has been hiking Pigeon Hill for decades.

Snapp said she has noticed how the changes in weather affect the peak color timing from year to year.

“From what I can tell, it depends how much rain we get in the late summer and into September, and what the temperatures are,” she said. “If it’s warm later, then it’s going to extend later.”

Her observations are pretty spot on, according to Maine forest pathologist Aaron Bergdahl.

“The recipe for really nice fall foliage is periodic rains throughout the summer, no drought periods. And a warm, wet spring followed by good growing conditions throughout the entire summer,” Bergdahl said, “cooler temperatures in the fall with adequate moisture. And that’s really been the issue for these last three years; we haven’t had really excellent moisture conditions consistently throughout the summer.”

Summer drought and warmer temperatures lasting well into the fall in Maine have caused unpredictability in the leaf peeping season. Warmer temperatures have delayed the onset of fall in Maine, pushing the color peak later.

Other factors are also stressing eastern forests. More intense storms, rainfall and invasive species harm trees and their leaves, and may already be reducing the vibrancy of fall colors and shortening the season.

Scientists refer to fall as the most understudied season in climate change research. There are still a lot of unknowns. Yet, understanding the effects of climate change on fall phenology is critical for regions like Down East Maine, where fall tourism is a billion-dollar industry.

“Fall foliage is important to the state of Maine, it makes up between 20 percent and 25 percent of the annual visitation to the state,” said Steve Lyons, the director of the Maine Office of Tourism.

He said if the season is more unpredictable, that can be a challenge. But there are also opportunities in encouraging people to visit Maine later in the fall instead of congregating in the summertime.

About 50 miles south of Pigeon Hill, there were thousands of leaf peepers at Acadia National Park, hoping they timed their trips just right to see the iconic fall colors paint the coastal landscape.

Environmental scientist Stephanie Spera was surveying people outside the visitor center in Acadia. Since 2019, she has been researching how changes in temperature and precipitation have affected the timing of peak fall foliage in the park, and if those changes affect fall visitorship.

Using satellite data, GIS, spatial statistics, climate models and a historical analysis of old monthly reports and newspaper clippings, Spera has found evidence of the shift.

“The timing of peak fall foliage has actually gotten about 10 days later than it was in the 1950s. It’s getting about a day later [per] decade. A little over a day a decade,” Spera said. “In the early 1950s, you’d come to Acadia the first weekend in October … that’d be your peak fall foliage. Now, it’s about right now, which is the second weekend of October even later.”

More visitors are coming to Acadia in the fall and staying later in the season, which affects park management and staffing of local businesses.

These changes are difficult to see during a single leaf peeping trip or outing. But for those who value the annual ritual of admiring fall leaves, the season is becoming more unpredictable.

“I came up to Maine every fall for last 20 years on this weekend. The trees are beautiful, I want to conserve that place. I want to preserve the people in the places, and the experiences that I love. So my kids, my grandkids can have them. And I think that’s why it should matter,” Spera said.

Lookabaugh said that’s why Downeast Coastal Conservancy organizes hikes in Washington County.

“By introducing people to these landscapes, and these places, they’ll maybe want to invest in them, become future stewards. And as stewards of the land, we can help mitigate climate change by conserving big pieces of land,” Lookabaugh said.

For Snapp, that connection to the landscape over time resonates in her family, who have owned a home at the bottom of Pigeon Hill for more than 100 years.

“It’s a tradition to come up here,” she said. “It’s ours to make sure it stays accessible and in good shape and enjoyable for people.”

Scientists and conservationists want Down East visitors to share that sense of stewardship, because the shifting leaves are a visible sign that change is already here.

This article appears through a media partnership with Maine Public.