Bald Eagles

Bald Eagles was originally published in the BFEC newsletter, Vol. 15/No. 1, Winter 2011. 

When it comes to natural resources, Knox Countians are lucky.  

Residents take pride in their beautiful, rolling landscape. The State Scenic Kokosing River winds through the hills with shimmering vitality. Access to enjoy the scenery by foot, boat or bicycle is fairly available. And on an average day, you might just see a bald eagle.

Only 20 percent of Ohio counties have medium-to-high bald eagles populations, according to the Ohio Department of Natural Resources (ODNR), and Knox County is one of them. But they do occur throughout the state, and in increasing numbers that were hard to fathom even ten years ago.

On the Brink & Back

Most of us are familiar with the story of DDT, a farm pesticide that trickled from fields into rivers with rain runoff, and contaminated the fish that are bald eagles’ favorite food.

Many birds became sterile or produced eggs with fragile shells. A low point in the population was hit in 1963, when just over 400 pairs remained in the U.S.

DDT was banned in 1979, and although trace amounts remain, the concentration slowly subsided. Governments also stepped in to help.

The bald eagle gained protection under the federal Endangered Species Act in 1976. In Ohio, repopulation efforts were made by placing eaglets from zoos in the nests of parents with non-viable eggs. ODNR radio-tagged birds, which provided information on movement and habitat needs. 

From a 1979 low of just four bald eagle pairs in Ohio, more than fifty pairs were recorded in 1999. Ten years later, that number quadrupled to over two hundred.

With almost 10,000 pairs recorded nationwide, the bird was removed from the federal endangered species list in 2007, though it remains a “threatened” species in Ohio.

Got Water?

With a wingspan of seven feet, white head and tail feathers, and fierce yellow eyes, bald eagles are striking.

They are found in every state in the U.S., though they are most numerous in Alaska, the Pacific Northwest, the Upper Great Lakes, and Florida.

All of these areas have the large bodies of water, where bald eagles hunt for fish with large, outstretched talons.

Water also helps explain their presence in Knox County, where they live along the Kokosing and Mohican Rivers, Knox Lake reservoir and quarries. (The public docks at Knox Lake are a good viewing spot).

In Ohio, counties bordering Lake Erie have the highest bald eagles populations, especially in the marshes and forested wetlands of the lake’s western border.

The presence of mature forests and large trees are another reason bald eagles are common in Knox County. A typical bald eagle nest is three to six feet in height and depth - not a job for a scrawny tree. It is part of our good fortune to have old, protected forests along the Kokosing River and elsewhere that offer this habitat. (We’re also fortunate to have many industrious people and agencies in the community who have worked to protect habitat and public access).

According to John Minard, who voluntarily monitors our bald eagle population and reports numbers to ODNR, we currently have four or five nesting pairs in the county and many juveniles.

With a four-fold population increase in the last ten years, have eagles regained their historic population levels, or even surpassed them?

That question is hard to answer due to lack of historical data. It has been estimated, though, that there were millions of bald eagles in North America before European settlement, and they were “common” in Ohio when settlers arrived (according to www.ohiohistorycentral.org).

Their numbers declined as forests were cut down, though populations were stable when the DDT hit the scene with catastrophic effects.

Regardless of whether they have regained historic numbers, two other human influences may be contributing to their current population boom.

The first is the spread of quarries and reservoirs. Much more open water habitat exists in Ohio now and through much of the U.S. than ever before. Two of the Knox County eagle nests are located near man-made bodies of water - Knox Lake and a private quarry next to the Kokosing River.

Another more recent phenomena is the enormous population of deer in Ohio. Populations have exploded in Ohio, which now offers great habitat for deer and lacks major historical predators (like wolves). While eagles don’t hunt deer, they do eat dead animals, or carrion, hit by cars or bullets. This food source is especially important in the winter time when fishing grounds freeze.

While eating carrion may not fit an idealized image of our national symbol, it certainly indicates something that we do admire: resourcefulness.

The next time you’re at the BFEC, keep an eye on the Kokosing River as it runs through the preserve. Sighting a bald eagle soaring above the river may be more common than it used to be, but it still feels lucky.