Geese That Can Take Down A Plane Are Staying Closer To Airports During Winter

Canada Geese DC
Canada geese take over a sidewalk that is covered in water during high tide at the tidal basin near the Jefferson Memorial and Washington Monument in Washington on September 20, 2016. Mark Wilson/Getty Images

Canada geese are menaces. They are loud. They poop everywhere. They can even take down planes. And if you live in a city, they are increasingly your neighbors.

A new study in The Condor, a journal published by the American Ornithological Society, followed the whereabouts of 41 geese. The researchers, most of whom were affiliated with the University of Illinois at Urbana–Champaign, attached GPS collars to Canada geese in Chicago to track them throughout the winter. Many of the geese were captured around the city's Midway Airport.

The study showed that Canada geese in Chicago had a better chance of surviving if they stayed in the city throughout the winter, which a majority chose to do despite the relative lack of food. All of the city geese survived, while less than half of the geese who left town did. (The researchers followed fewer than 50 birds.) Several hung out in railyards and on rooftops, in addition to more traditional areas like parks. And, of course, the airport.

Geese pose a real threat to airplanes. Remember Chesley "Sully" Sullenberger's "Miracle on the Hudson" landing in 2009? That was a Canada goose's fault. There have been dozens of other goose-related airplane incidents. They have been pulled into engines, caused fuel tanks to rip off and cracked windshields. They've even caused total destruction of planes.

Obviously, those issues can be expensive. If an airplane takes a goose in its engine—the common technical term is ingested—it may need hundreds of thousands of dollars in repairs.

Canada geese horde
Canada geese gather on the waters of the Washington Channel in Washington, D.C., on February 6, 2007. Mark Wilson/Getty Images

People are trying to protect the planes and their passengers. The government of New York state would prefer to see the number of birds decrease by more than half, and they are not just asking nicely. In 2012, about 700 geese were culled from an area around John F. Kennedy International Airport. The meat was processed and donated to food pantries, Politicoreported. Corn oil can prevent geese eggs from hatching in the first place. Airport authorities have also hired falconers to scare away the geese.

And yet the population of Canada geese has taken off since the mid-1990s, according to the Cornell Lab of Ornithology. Understanding how or why the geese survive the winter could help population-control efforts.

Making noise and not feeding geese could be especially effective at driving the birds away during the coldest time the year, the authors of the Condor paper noted. Given that food is scarce, geese have to save their energy and wouldn't be able to just move around the city. Eventually, they'd have to go out to the country for food, where they are more likely to be killed.

Of course, those country birds are just as capable of doing damage. According to the National Transportation Safety Board, a Smithsonian Institution analysis concluded that the geese that took down Sullenberger's US Airways flight in 2009 weren't even locals—they were migrating birds just passing through.