Of reported sightings between 2020 and 2025 in Acadia, about 60% occurred just in 2025. “I believe this is because there were some bear conflicts early in the year,” said a lead researcher.
Get Instant Access to This Article
Subscribe to Mainebiz and get immediate access to all of our subscriber-only content and much more.
- Critical Maine business news updated daily.
- Immediate access to all subscriber-only content on our website.
- Bi-weekly print or digital editions of our award-winning publication.
- Special bonus issues like the Mainebiz Book of Lists.
- Exclusive ticket prize draws for our in-person events.
Click here to purchase a paywall bypass link for this article.
In recent years, researchers have fielded an increasing number of reports of black bear sightings on Mount Desert Island.
But does that mean there are more black bears than ever?
A new study is the first step toward establishing a population baseline, along with movement patterns and genetic relationships, with the ultimate goal of reducing conflicts between humans and bears and safeguarding both.
“This work fills a major information gap on MDI,” said Brittany Slabach, a faculty member and biologist at College of the Atlantic. “We’re hoping the community will help us by reporting observations so we can have a clearer picture of the ecology of bears on the island.”
The project is being conducted in collaboration with the National Park Service and the Maine Department of Inland Fisheries and Wildlife. The latter estimates there are 25,000 to 27,000 black bears in Maine.
Increased reports
Historically rare, black bear sightings in Acadia and the surrounding area have increased in the last few years, most notably during the summer of 2025, on both Mount Desert Island and Schoodic Peninsula, according to the Schoodic Institute, Acadia National Park’s science and research partner.
Of 70 to 80 reported sightings between 2020 and 2025 in Acadia National Park, about 60% occurred just in 2025.
“I believe this is because there were some bear conflicts early in the year, so people were more aware of bears,” Slabach told Mainebiz.
Changes in bear population and behavior prompted researchers to assess whether a resident bear population exists on the island and how bears are using its national park land, villages and private property.
With approximately 70% of MDI encompassed by Acadia, the study could provide insights into the MDI bear population that could be used to inform management.
Hair snares
Slabach is leading undergraduates in a project to collect bear data, which previously have been pretty sparse on MDI, she said.
The team is finishing its first summer field season.
“This is the first year of a two- to three-year study, so we don't have answers yet but lots of great new information,” she said.
Determining population and movement patterns will help inform management strategies with a goal to reduce conflict, she said.
The study’s primary technique is the use of “hair snares” in the park. Hair snares are a widely used, passive wildlife monitoring technique to collect DNA samples. Each snare consists of barbed wire wrapped around several trees with a scent lure placed in the center. When a bear investigates the scent, it might leave behind hair on the wire, allowing researchers to extract DNA and estimate population size, relatedness and movement patterns.
“This approach lets us gather high‑quality data in a safe, cost-effective way to better understand how bears are using MDI,” Slabach said.
Game cameras are mounted with the snares, providing visual data.
The team is monitoring 14 snares and 28 cameras in the park.
“Snares are baited every seven weeks during the spring and summer and checked every 10 to 14 days for hair, so it's a logistical puzzle to make sure things are running smoothly,” said Slabach.
The plan is to add at least three to five more sites next year.
Baseline information
An increased number of sightings does not mean more bears.
“Sightings information does help us to understand areas bears might be hanging out and past sightings data does give us important baseline information on areas bears have been seen prior,” she said.
The partners also launched a survey, asking people to report sightings of bears or scat, both present and past.
Alternatively, sightings can be emailed to MDIbearproject@gmail.com.
“So far this year, we have nearly 50 sightings through this effort, which is incredibly helpful,” she said.
For people who come across scat, a scat collection kit is available for those willing to collect it or have the team collect it. Scat collection helps increase DNA sample size and helps the team investigate food habits.
If a bear is getting into trouble — getting into trash or a bird feeder, for example — people should report that directly to Maine Department of Inland Fisheries and Wildlife or the National Park Service, she added.
Eight undergraduates have participated in the project so far.
“These are great learning opportunities for students as they are collecting real-world data that has direct implications for conservation and management needs,” said Slabach. “As an inter-agency collaboration, they also gain first-hand experience as a collaborative partner on a project.”
The project could expand to other conservation properties to get better coverage of the island. Sightings have also come in from homeowners and campgrounds, she added.
