In 1975, the Ohio Department of Natural Resources was aware of only four bald eagle nests in all of Ohio.

Last year, the number of nests was estimated at 350, according to Laura Kearns, a wildlife biologist for the Ohio Department of Natural Resources’ Division of Wildlife.

So it is not altogether rare that Brown Township resident Ken Whelan had spotted a bald eagle in early March soaring above his Elliott Road residence, just outside Hilliard.

But it still is a majestic sight, Whelan said.

“I figure it has a nest around here somewhere,” he said.

Whelan once worked at the Akron Water Pollution Control Station, a waste-water treatment plant in the Cuyahoga Falls Parks & Recreation system, and while there, he had observed bald eagles on several occasions.

He also saw them at his brother’s cabin in West Virginia.

“There was one (nest) on a mountainside there; I was shocked because it was 5 or 6 feet in diameter,” Whelan said.

But Whelan said he has not found a nest near his Elliott Road residence.

The bald eagle, the national bird of the United States, once was among Ohio’s endangered and threatened species, but in 2012, it was removed from that status, Kearns said.

From its low of four known nests throughout Ohio in 1975, the number of nests increased to 200 by 2012, she said.

One of the best known nests is along the Olentangy River in Highbanks Metro Park, where an observation deck faces it.

Another is near Grandview Heights, where one of the nesting eagles recently was found dead.

Before 2012, the ODNR performed an annual nest census for bald eagles, Kearns said. The counts are performed for all endangered and threatened species, she said.

The ODNR does not track sightings of bald eagles, Kearns said.

Kearns credits the resurgence in the number of bald eagles from 1975 to 2012 to a variety of factors, including the United States’ ban of synthetic chemical DDT that once was used as an insecticide, efforts by a variety of wildlife organizations to rehabilitate injured or compromised bald eagle chicks and the practice of “cross-nesting.”

Two is the optimal number of baby bald eagles per nest, Kearns said.

When possible, the ODNR and other wildlife organizations would remove one baby from a three-baby nest and place it in a one-baby nest, she said.

These practices allowed the number of bald eagles to increase through 2012, Kearns said.

When the number of known nests for a bird species reaches 200, the ODNR no longer conducts a nest census but rather an annual survey, Kearns said.

The ODNR has five designated areas of 10 square miles each in which nest surveys are conducted, she said.

Based on the numbers of the nests within these areas, an estimation is made for the total number of nests, Kearns said.

In 2019, Ohio had an estimated 350 bald eagle nests and an estimated 1,000 bald eagles.

The number of bald eagles is based on two per nest but also adding the estimated number of bald eagles that are five years old or younger, too young to breed, Kearns said.

The lifespan of a bald eagle in captivity can exceed 50 years, whereas those in the wild often live 20 to 30 years but sometimes longer, Kearns said.

Whelan said March 23 he continues to look for the bald eagle he has spotted four times through March 14, each time on Elliott Road.

“I am always looking at Mother Nature’s creations,” he said.

kcorvo@thisweeknews.com

@ThisWeekCorvo