Eagle population surges in Illinois

  • By Taryn Luntz
  • Medill News Service
  • January 12, 2007 @ 2:14 PM
As the bald eagle population soars in Illinois, sightings are becoming increasingly likely in the Chicago area and elsewhere in the state.

The majestic raptor, whose national numbers plummeted to as low as 450 nesting pairs during the 1960s, has recovered steadily enough to be taken off the list of nationally threatened species by the U.S. Fish and Wildlife Service - a move the organization is expected to make next month.

During 2004's Midwinter Bald Eagle Survey, officials and volunteers counted almost 4,000 eagles in Illinois -- up from about 1,000 in 1978. Numbers dropped slightly in 2005 because of blocked survey paths and in 2006 because of an unusually warm winter.

The Illinois Audubon Society is currently coordinating the 2007 survey through January 17th. Sixty volunteers, including field biologists from the Illinois Department of Natural Resources, drive 45 designated routes and count the eagles they see along the way. 

Though officials admit the count not quite an exact science, the same routes are driven every year and the survey is a good indicator of eagle population trends.

While the official count is based on a summer survey of eagle nests, the U.S. Geological Survey coordinates the midwinter count to track eagles who winter in the contiguous U.S. but don't necessarily nest here. The birds fly into Illinois from northern areas, where iced-over rivers prevent them from hunting for fish.

That makes winter the best time to spot an eagle overhead in Illinois.

"We're the southernmost migration for a lot of the birds," said Kevin Ewbank, the lead park ranger at the Illinois Waterway Vistor's Center across the river from Starved Rock State Park, near Ottawa. The dam at the visitor's center keeps water flowing when other parts of the Illinois River are frozen, attracting hungry eagles.

"For the past 10 years we've been seeing higher numbers every year," Ewbank said. "Two years ago in February, we actually had a high count of 115 at one time."

Visitors can see the imposing birds roosting on trees, swooping down to the water and occasionally stealing fish from one another.

Bald eagles were so threatened by land developers and the pesticide DDT that they were once likely to be spotted in the U.S. only in wildlife documentaries. But the protection they recieved in 1978 under the 1973 Endangered Species Act, as well as the 1972 ban of DDT, prompted a comeback so successful that they now number over 7,000 nesting pairs, with even more flying in during the winter.

While the Mississippi and Illinois Rivers in the western part of the state house the largest numbers in Illinois, the birds are also increasingly being spotted around the Chicago area.

"You can see bald eagles regularly in northeastern Illinois during migration," said Bob Fisher, former president of the Bird Conservation Network and the DuPage Birding Club. Eagles that fly in for the winter usually arrive in November and return home in March -- two good months to spot them.

Fisher also said a juvenile eagle has been sighted regularly along the Fox River in Lake County.

A pair of eagles began nesting in an industrial area on the Little Calumet River on Chicago's Far South Side in 2004 -- the first bald eagles to nest in Chicago for more than 100 years.

Though the site is far from scenic, experts believe the birds chose it because it is relatively isolated and posed little threat to them from human populations.

Though bald eagle sightings are still rare, they are becoming less so.

"Anywhere you're near water, your chances increase greatly that you're going to see eagles -- certainly at the watershed of the Illinois River leading up into Chicago," said Tom Clay, Executive Director of the Illinois Audubon Society. "The odds are getting better every day that a person's going to see one."

Eagle aficionados who prefer not to leave it up to chance can attend the free Bald Eagle Watch Weekend at Starved Rock Lodge and the Illinois Waterway Visitors Center on January 27th and 28th. Multiple sightings are almost guaranteed, though eagles will probably number fewer than the 115 they had two years ago.

"This year is an anomaly because of the weather conditions," Ewbanks said. "Without the ice this year we really don't know what we've got out there."