News

Chicago Gulls Go Green

Seen a brightly colored gull lately, or one sporting flashy tags on its wings? You're not losing your mind--you've just spotted an (unwitting) participant in the Ring-billed Gull Management Program.

The program began in the spring of 2007 as a joint effort by the U.S. Department of Agriculture's Wildlife Services and the City of Chicago's Department of Environment, designed to discourage the birds from nesting here. The gulls, named for the black ring circling their yellow bill, were only occasional visitors here until the mid-1970s. However, by 1999, 134,000 of these birds had decided that Chicago-area landfills, trash cans, and beaches made a fine home.

By April 2007, the gull population had soared by 500 percent in some locations. In addition to other various nuisances attributed to the gulls, their droppings are believed to be a possible cause of elevated E. coli levels in Lake Michigan, which have resulted in many beach closures.

The program hopes to gain insight into controlling the gulls through tagging and monitoring. Wildlife Services personnel wing-tagged more than 1,300 nesting gulls at Lake Calumet (blue and yellow tags) and at Dime Pier near Navy Pier (orange and green tags) in 2007 and 2008, along with help from biologists from the National Wildlife Research Center in Ohio. They also marked other gulls with nontoxic dyes, leaving not a few members of the public puzzling over their hue. Marking the gulls will help researchers learn more about their movements and lead to long-term management strategies. Birders from as far as Iowa, Lake Ontario, and even Florida have reported the marked gulls.

People who see marked gulls in 2008 can e-mail john.w.hartmann@aphis.usda.gov. Include the date, time, and specific location of the sighting, the color of the tag or dye, the number of marked gulls seen, and the observer's name and phone number. The study ends in December, and results will be released in early 2009.

— Betsy J. Green