Bald eagle population increases by 150 percent

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Bald eagle feeding chick
A female bald eagle feeds her three-week-old eaglet in a nest in Tuscarawas County. According to a recent survey by ODNR Division of Wildlife, the number of bald eagle nests in Ohio has increased by 150 percent since 2012. Photo by Bob DeMay.

Gov. Mike DeWine announced the good news at his press conference April 22: A survey showed 707 bald eagle nests in 85 of Ohio’s 88 counties. In 1979, he said, there were only four nests in the entire state.

“The bald eagle is a symbol of American strength and resilience, and the eagles’ comeback in Ohio and across the country proves that we can overcome any challenge when we work together,” DeWine tweeted.

Citizen science census

More than 2,500 Ohioans responded to a “citizen science census” between Feb. 1 and March 31, said Laura Kearns, a wildlife biologist with the ODNR Division of Wildlife, who works at the Olentangy Research Station. She was tasked with overseeing the census — literally and figuratively. “I was the person on the computer, managing the data,” Kearns said.

The public survey was done on wildlife.ohiodnr.gov/reportwildlife, where folks can still report nest sightings if they wish.

Kearns was also overseeing from a higher altitude. She accompanied Division of Wildlife pilot Joe Barber on his flights to confirm nest locations from the air. Unfortunately, he had to fly solo after the COVID-19 isolation order. But he and Kearns found support from wildlife officers, ODNR staff, and plenty of volunteers who helped confirm nest locations from the ground.

Geographic Information Systems biologist Anthony Mosinski used new technology to compile geographic information. The division’s graphics section created a map with the number of nests in each county.

“It was really a team effort,” Kearns said. The Division of Wildlife had gotten the word out through press releases, social media, and the Division’s Wildlife Diversity Conference in early March, which attracts more than 1,000 bird, animal, plant and bug enthusiasts to The Ohio State University campus each year.

“We did not expect that many responses” to the survey, Kearns said, noting that there were more than 1,000 in just the first week. Nor did they expect that many nests.

Dropping numbers

The bald eagle was made the national symbol of the United States in 1782. It is estimated that there were 100,000 nesting eagles in the “lower 48” at that time. By 1963, that number had dropped to 487, according to the U.S. Fish and Wildlife Service. The bald eagles’ decline began in the 1800s with loss of habitat and being shot by farmers and ranchers who perceived them as threats to livestock.

The decline worsened after World War II when DDT came into common use, first to control mosquitoes and other insects, then as a pesticide in crop production. The chemical leached into the eagles’ food supply causing thinning of egg shells, which would then break during incubation or fail to hatch. The EPA banned DDT in 1972, “but it took a while for the chemical to flush out of the environment,” Kearns said.

Comeback

The Endangered Species, Clean Air and Clean Water acts of the early 1970s also helped bring the eagles back. So did conservation programs like “fostering,” she said.

In Ohio, fostering programs moved eaglets hatched in captivity from zoos to nests where eggs had failed to hatch. Wild eagle parents could then raise the eaglets in a more natural environment, and boost wild eagle numbers.

In 2007, bald eagles were taken off the federal endangered species list. They were removed from Ohio’s endangered species list in 2012, the same year the Division of Wildlife conducted the last statewide survey. At that time, there were 281 nests in Ohio.

After that, surveys were done “only on selected areas just to give us a sample,” Kearns said. The statistics derived from the samples showed the bald eagle population was increasing. Still, wildlife officials didn’t expect a 150% increase, which is the difference between the 2012 and 2020 surveys.

Still protected

Though they published a map with numbers of nests for each county, wildlife officials decided not to reveal specific nest locations. There have been reports of people trespassing on private property and others of people flying drones near nests. That could disturb the birds and cause them to abandon the nest, Kearns said.

Even though they are off the endangered lists, bald eagles — and golden eagles — are still protected under state and federal laws. Originally passed in 1940, the Bald and Golden Eagle Protection Act has been amended several times to stiffen penalties for killing, trapping or disturbing the birds.

Wildlife officials suggest that viewers stay at least 330 feet away from eagles’ nests. “We want to avoid ‘loving things to death’ in nature,” Kearns said. “It’s just as important for us to practice social distancing from nature as it is for us to social distance from each other during the coronavirus.”

Webcam watching

Watching eagles on webcams is one way to keep a safe distance. Ashtabula Area City Schools have a live stream of Pride and Joy as they care for their two chicks at lakesideeaglecam.com.

Redwood Elementary School in Avon Lake has a 360-degree camera and two other live webcams pointed at Stars and Stripes as they care for their three chicks. Cleveland Metroparks is waiting to see if the eagle pair at Rocky River Reservation will be parents of triplets three years in a row.

Bald eagles mate for life — unless something unfortunate happens — and return to the same nest, or at least the same territory, every year. A pair in Columbus had their nest fall down in a windstorm last winter but rebuilt in the same tree this spring, Kearns said.

Bald eagles do not develop their characteristic white heads — and white tails — until they are five years old, she said. Till then, their heads are mostly brown with different patterns of white each time they molt. It is difficult to tell the male and female apart until you see them together; the female is usually bigger than the male.

Life cycle

Females start laying eggs in early- to mid-February, depending on where they are. The incubation period is a little over a month, and both males and females can sit on the eggs, Kearns said. The chicks start hatching late March to mid-April and stay in the nest 10 to 12 weeks.

Between early June and mid-July, “they’ll leave the nest but may stay around and go back to the nest at night, or to feed,” she said. The parents continue to feed them for some time and also teach them to hunt.

It’s no accident that the survey found the most nests in the counties around Lake Erie — 90 in Ottawa County alone. The area is prime eagle habitat with a number of coastal wetlands, and the four bald eagle nests in the late 1970s.

In the rebound of eagle populations, Ohio may have lagged behind other Great Lakes states like Minnesota and Wisconsin where there are more wetlands.

“But honestly, there has been an incredible comeback pretty much everywhere,” Kearns said. “If the eagles are doing well, it may indicate that our environment is doing well,” she said. “And that’s a benefit to all of us.”

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