A bald eagle perches atop a tall evergreen on one of the many islands in Cobscook Bay on July 13, 2018. Credit: Aislinn Sarnacki

AUGUSTA, Maine — In 1967, bald eagles were nearly on the verge of disappearing from the Maine landscape. Today, they are thriving.

The Department of Inland Fisheries and Wildlife announced that nesting pairs of eagles increased 16 percent over the past five years, growing from 632 to 733.

The count, which was completed late this summer, was done in 2018 by aerial survey, which was supported by Wildlife and Sportfish Restoration funds and the Maine Outdoor Heritage Fund.

There were only 21 nesting pairs in 1967.

“We documented increases statewide in all 16 counties, but the highest population growth rates continue a recent shift westward and northward across the state,” Charlie Todd, the endangered and threatened species coordinator for DIFW, said in a release.

Todd has been instrumental in guiding bald eagle recovery in Maine since the late 1970s. He said nine counties have eagle populations that are growing faster than the statewide average.

“Downeast Maine remains the state’s stronghold and boasts the highest density of breeding eagles in any region between the Chesapeake Bay area and Nova Scotia,” Todd said.

A crew of four warden pilots and 17 wildlife biologists logged 240 hours in MDIFW aircraft documenting nests throughout the state. According to the release, late-season snowstorms in March forced many eagles off their eggs, delayed egg-laying for others and destroyed or damaged many more nests than normal.

The survey was timed throughout the state to match periods in the breeding cycle when eagles are mostly at nests. Nesting dates can vary by six weeks among neighboring eagle pairs.

Most pairs make only one breeding attempt each year.

MDIFW evaluated more than 1,800 traditional sites over an eight-week period, checking all nest locations documented since 1962. Eagles are usually very loyal to nests and relocate only out of necessity.

A nest in Blue Hill holds the record for continuous use, 41 years since 1978.

Along with the tally of 733 nesting pairs, the crews noted single adults at 54 other nests and no eagle activity in 90 former nesting territories. Todd estimated that they may have missed as many as 40 pairs, which is the highest count of nesting eagles ever in Maine.

A nest in the Swan Island Wildlife Management Area in Sagadahoc County measured 20 feet vertically when it was first found in 1964 and biologists conservatively estimate it had been in use for at least 60 years.

Bald eagles were removed from the state endangered and threatened list in 2009. They were originally listed as endangered in 1978.

The low point for bald eagles in Maine occurred in 1967 when only 21 nesting pairs were found, and they raised only four fledgling eaglets. The bald eagle has long been revered as a majestic bird, our national symbol and an indicator of environmental quality. Now it’s one of the premier examples of conservation success.

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