top of page
  • MLCA

Keeping an Ear out for Sharks

Last year in August a woman from New York City was killed by a great white shark while swimming off Harpswell. The tragedy generated immense media attention and highlighted the unseen presence of great white and other sharks in Maine waters.

In 2020, the Department of Marine Resources (DMR) began a collaboration with the Massachusetts Division of Marine Fisheries, the Atlantic White Shark Conservancy, and James Sulikowski of Arizona State University to monitor white sharks passing along the coast.

Photo Courtesy: New England Aqarium

DMR staff installed eleven passive acoustic receivers that year in southern Maine waters. The acoustic receivers capture data emitted from tags that have been placed on great white sharks. Currently, there are approximately 210 great white sharks that have been tagged as part of the Atlantic White Shark Conservancy’s research work.

“The questions that can be answered are based more around movement patterns and habitat use than tracking every single individual,” explained Erin Summers, director of the Division of Biological Monitoring in DMR. “We can learn things about the times of year they tend to show up in Maine waters, when occurrence peaks, times of day that are more common, and residency patterns.”

The receivers were retrieved in the fall and data was downloaded by DMR science bureau staff. The 2020 data recorded 14 visits along the coast by great white sharks and one from a blue shark and one from a sand tiger shark.

DMR now has 32 passive acoustic receivers in the water listening for passing sharks, such as the great white shark.

In 2021, DMR expanded the project to 32 acoustic receivers deployed in mid-coast and southern near-shore areas. The sites were chosen to learn more about the migration and habitat use of great white sharks in the Gulf of Maine and thus better protect public safety.

Great white sharks are common along the entire East Coast and in Canadian waters. “White sharks are pretty opportunistic and will feed on fish, including other sharks, when they are smaller and then switch to a marine mammal diet when larger,” Summers said. “Their numbers are experiencing a rebound after years of protection and the simultaneous resurgence of seals in the region, particularly on Cape Cod.”

In July DMR introduced a new method for the public to submit shark sightings to the department. An online form offers a convenient way to submit photos and a description to the DMR science bureau.

Once the form and photos are submitted, a DMR scientist reviews the information and responds via email either confirming the shark species or requesting additional information. The data will be shared with the New England White Shark Research Consortium, which includes fisheries officials in Maine, Massachusetts, New Hampshire, Rhode Island, and Canada as well as marine conservation groups and federal and university researchers.

Sightings data will also be transmitted to the Atlantic White Shark Conservancy to be uploaded to the organization’s Sharktivity app. The app provides users with a recap of shark activity detected by acoustic receivers, in addition to shark sightings. Information and app downloads can be found at


Maine Department of Marine Resources also has a way for boaters to upload pictures of sharks and a form to document the sighting. CLICK HERE

Many people mistake other species of fish for white sharks," said Erin Summers, Director of DMR's Division of Biological Monitoring. "Species like Ocean sunfish or basking sharks are often mistaken for white sharks, so this new online tool will help people gain a better understanding of the species found in the Gulf of Maine."

Once the information has been received, a DMR scientist will review it along with any images or video submitted and will respond via email with information either confirming the species or requesting additional information.

Recent Posts

See All

Fishermen's Data, Fishermen-Owned

Fishermen pride themselves on what they know. The ocean is their workplace, and they have unique and valuable knowledge of specific ocean areas. This knowledge is their trade secret and is what makes


bottom of page