Scientists at the University of Maine at Orono used a drone to take this image last summer over a colony of double-crested cormorants on an unidentified island. The researchers will use similar technology this summer off Elm Island in Harpswell to conduct annual population counts of species such as the cormorant. Contributed / Meredith Lewis

Harpswell residents might notice a tiny flying machine periodically hovering in the air off Elm Island this summer, as researchers at the University of Maine at Orono employ drone technology to monitor seabirds in the area.

Researchers are interested in studying colonies on as many as six islands, including Elm Island, of double-crested cormorants, several species of gulls and the eider, a common heavyweight sea duck, all known to nest locally. The work will begin in late April or early May and finish in July or early August.

The project represents growing interest among researchers in doing a common annual event in a whole new way, according to Logan Kline and Meredith Lewis, graduate research assistants with the university’s ecology and environmental science program.

“It’s something we want to explore,” Lewis said this week.

The task sounds simple enough: visit colonies of sea birds and do a headcount, something that scientists have been doing in Maine and nationwide for decades, but Kline said researchers prefer not to do the traditional point-count method – literally walking into a flock of birds to point at and count each one.

For one thing, she said, researchers worry about scaring nesting birds away from their eggs, since sometimes they don’t come back, leaving the young neglected and unprotected.

“If you’re walking through a colony, you’re more likely to disturb breeding birds,” she said.

The sheer logistics of direct observation is a problem, too, Lewis said, given there are hundreds, if not thousands of islands off the Maine coast where birds nest.

“It’s a monumental task, and a difficult one,” she said.

More recently, Kline said, researchers have opted for plane-based observation, flying overhead and taking pictures. This works, she said, but planes can’t get very close to the birds and the process can be expensive. A drone, by contrast, is cheaper to buy and, while still restricted by Federal Aviation Authority guidelines, can get closer to the colonies for overhead observation. Researchers use typical civilian-style drones,  such as those available in most electronics stores.

Kline said the project also uses new artificial intelligence that will allow researchers to more accurately analyze the images the drones capture. Typically, both researchers said, numbers of birds per colony can range from as few as a dozen to as many as thousands. While Kline said she doesn’t expect the recorded number of birds to vary widely from data acquired the old-fashioned way, it will be easier to get with less impact on the aviaries.

“You’re getting that information for less effort,” she said.

Lewis said the university conducted a similar counting project last year elsewhere in the state, and she believed it may be the only project in the state using drones to monitor bird colonies. She said she didn’t know exactly how many similar projects may be going on elsewhere in the country, but cited a March 2020 paper published in the international scientific journal Scientific Reports which indicates, “The popularity of using unmanned aerial vehicles (UAVs) to survey colonial waterbirds has increased in the past decade.”

Kline said she expects observations using drones or similar vehicles will continue, especially for species such as the double-crested cormorant, a species she said researchers fear may be in decline and is especially sensitive to human contact.