One of the most exclusive neighborhoods in Lake County is sheltered by shallow coves on either side of a peninsula jutting into the Fox River. And though it's early in the afternoon, the wild bunch that lives there is pretty rowdy.
"It sounds like a jungle -- so many birds calling," said Allison Frederick, environmental communications specialist with the Lake County Forest Preserve District, during a recent visit by boat. "There's a lot going on."
Indeed, the chatter of great blue herons, egrets and double-crested cormorants is nonstop, and the frequent comings and goings of the many inhabitants is a show of aerial agility.
But it is the rare presence of a pair of nesting bald eagles in their midst that makes this wooded area one of the unique addresses in Lake County and an encouraging sign for nature lovers.
"It's a symbol of success that we have (bald) eagles nesting on the Fox River. Who would have thought?" said Kim Compton, an education program coordinator for the McHenry County Conservation District, who made the find by chance.
Situated in a dead tree about 70 feet above the water, this is thought to be one of five active bald eagle nests in the Chicago area and the second in Lake County. One chocolate brown eaglet -- it won't develop the distinctive white head and tail feathers for four or five years -- is visible.
"It's a fairly big deal. I had only known of one other (nesting pair in Lake County), and that was in the Chain O' Lakes," said Steve Bailey, an ornithologist with the Illinois Natural History Survey. "They have become fairly common throughout the state in other areas, but the Chicago area had been without breeding eagles until a few years ago."
With a wingspan that can reach 8 feet, the powerful bald eagle was designated the national bird in 1782. By the 1960s, however, it faced extinction, and in 1978 it was listed by federal authorities as endangered in most states.
They were removed as a threatened and endangered species in 2007 but still are protected under federal law.
Habitat protection, the banning of the pesticide DDT and public conservation measures reversed the eagles' fortunes. The nest overlooking the Fox River is local evidence of what the U.S. Fish and Wildlife Service describes as a remarkable recovery.
Still, they are far from plentiful in this area, and seeing the majestic bird is a memorable experience.
"They're huge and have a really, really slow flap. It seems effortless," Frederick said. "The wingspan -- it triggers something in your brain that you're looking at something different."
On April 21, Compton was leading a canoe trip to an established heron rookery along a bend in the river near Tower Lakes. In what she described as a "happy accident," Compton noticed an adult eagle overhead. As other birds scattered, she shifted position and saw the eagles' nest among many others.
"They're starting to come back more and more, but to actually see one for the first time and know it's a new resident was very exciting," said Compton, who reported her find to Lake County Forest Preserve District officials. "The thing we were most surprised about was all the other birds were still there."
Frederick estimated there may be as many as 75 nests stacked and spread among the trees like a neighborhood of bird condos. But there is only one eagle pair, and that it is nesting and caring for a young one made the find even more notable.
It's not unheard of to see migrating bald eagles along the Fox or Des Plaines rivers. And for a few months in the winter, the locks and dams of the Illinois River near Ottawa and the Mississippi River at the Quad Cities are dense with eagles that feed in open water.
And for a second straight year, bald eagles stopped for a time last February on the Fox River near the Gail Borden Public Library in Elgin. The sweeping west-facing library windows were lined with awe-struck patrons, and binocular checkouts were popular.
"But nesting bald eagles -- that's what's very rare," Frederick said.
According to the U.S. Fish and Wildlife Service, bald eagles have been building nests in the Chicago area since 2004 but didn't successfully fledge a young one until 2007. There are 13 bald eagle nests in the seven-county metropolitan area, but only four were considered active for the 2012 breeding season, the agency reported before Compton's discovery.
Eagle nests in the news include one on the Calumet River near an industrial site where Chicago police for years wanted to build an outdoor shooting range. The plan was dropped this past March after the department learned of the eagles and heard from community groups.
Another notable active nest is on private property at Mooseheart Child City & School near Batavia. A pair of bald eagles fledged two eaglets in both 2009 and 2010. Last year, windstorms blew the nest and two little ones out of the tree. A man-made nest was placed in an adjacent tree, but the eaglets eventually had to be relocated. The adults returned this year and built a nest in their original tree.
The other nest in Lake County had been on Ackerman Island near Fox Lake. That too was blown over last summer in a windstorm.
"They had three young in the nest at the time," said Brad Semel, natural heritage biologist for the Illinois Department of Natural Resources. They survived and relocated about a quarter-mile south, he said. In that case, herons abandoned their nests and eggs when the eagles arrived.
Bald eagles already were on the decline because of habitat loss and other factors when the pesticide DDT was introduced after World War II. It was washed into waterways and absorbed by plants and fish. Eagles were poisoned when they ate the fish.
Chemicals also thinned the shells of the eagles' eggs, which often were crushed during incubation. The eagles' recovery began in 1972 when the use of DDT was banned.
"It's still a relatively susceptible population," Semel said of eagles in this area.
Experts aren't sure what is spurring the eagle nesting activity here. But the combination of sheltered areas along open water, a good food supply and ample number of sturdy trees to hold nests that can be 10-feet across and weigh half a ton is thought to be a draw as the birds expand their ranges.
"The population could grow quite a bit in Lake County because there's lots of good habitat," Bailey said.
There is no specific program in place, but experts will continue to monitor eagle activity.
"It's something to note and be excited about," Frederick said. "Put it on the species list and keep an eye out for more."
Eagles: Lake County offers plenty of good habitat