Visitation dipped 2.4% last year compared to 2021, when more than 4 million people came to the park, according to federal data.
Close to 4 million people visited Acadia National Park last year, nearly 100,000 visitors shy of 2021's record-breaking total.
Eric Stiles, president of Friends of Acadia, said the park was short-staffed over the summer, and those who did work were stretched to their limits. A lack of affordable housing on Mount Desert Island is the major threat to sustaining the park's operations, he said.
"If you had asked me a year ago if my No. 1 project was going to be affordable housing, I would have thought you're crazy," Stiles said. "What does it have to do with conservation? Absolutely everything."
Stiles said Friends of Acadia is exploring solutions, such as buying a former hotel or bed and breakfast to convert to temporary housing for employees, and eventually building more permanent units in partnership with the park.
Though two consecutive years of record-breaking visitation have been challenging, Stiles said it means that more people have been able to experience Acadia. But the park needs more funding from Congress to make these trends sustainable, and visitors should do more to reduce their physical impact on the environment, he said.
"This is where it really becomes a question of how the visitation occurs, by way of bus versus car," Stiles said.
Stiles said he's hopeful that a planned center in Trenton will eventually serve as a more convenient spot where visitors can park, purchase park passes and ride the free Island Explorer bus to Acadia.
The bus system hasn't rebounded from pre-pandemic levels, despite record-breaking visitation. Ridership last year was down 36% compared to 2019, the last full year that the bus ran a full schedule before the pandemic.