Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=86297
Story Retrieval Date: 4/16/2014 2:36:49 AM CST
In the battle between geese and humans in Chicago, Grant Park is one of the primary fronts.
Bob O’Neill, president of the Grant Park Conservancy, said that the park’s spacious lawns and high pedestrian traffic make the issue particularly challenging for the site.
“We have really been putting pressure to get the [goose] population reduced,” O’Neill said.
O’Neill said the summer crowds that patronize festivals and movies at Grant Park deserve a sanitary environment. He said having a too-dominant species also harms other animals – wildlife forced out and even dogs, who become ill after eating the goose droppings.
O’Neill said his organization is investigating landscape changes to make the park’s 319 acres less attractive to fowl. Planting trees can make it difficult for geese to find enough space to land.
The area north of the Petrillo bandshell would be a prime candidate for more trees, but O’Neill said a problem with that is the trees would block sightlines when movies are shown in the park.
O’Neill points to the lack of geese on the Great Lawn of Millennium Park as proof that minimizing the landing zones for geese can have a big impact. The acoustic trellis that covers the grass disrupts geese flight patterns, he said.
The goose-repelling properties of the trellis are welcomed but unintended. “Frank Gehry is clever but not that clever,” O’Neill said.
For the second year in a row, park officials paid for a third-party company, Wild Goose Chase, to coat eggs with corn oil in March, the start of the nesting season. The oil clogs the porous shell of the egg and prevents hatching.
O’Neill said the egg-oiling measures are an improvement over experiments in the past. “I have noticed, in areas, a reduction,” he said, “but it is going to take a few years to see the effect.”
The average Canada goose produces 1.8 pounds of droppings per day – more than the weight of two unopened soda cans.
That piles up to more than 650 pounds per year. Multiply that by the booming goose population in Chicago parks, and you have a mess.
Park District officials, who track this sort of stuff, have been working to deter the prodigious poopers. They have fought back with border collies – who harass the geese and keep them from getting comfortable; chemical sprays – which make the grass appear unpalatable and ruins their appetites; and corn oil – used on eggs to prevent them from hatching.
“I get complaints constantly,” said Bob O’Neill, president of the Grant Park Conservancy, a group that works to promote the park. “It makes for an unpleasant experience to have goose droppings all over when you are trying to enjoy the park.”
Canada geese are attracted to lakefront parks because of abundant food and lack of predators. Zvez Kubat, spokeswoman for the Park District, said some geese are so comfortable that they no longer migrate south for winter.
“[Grant Park] is like a salad bar for geese,” O’Neill said. “The issue is that they are getting lazy.”
He said the largely vegetarian birds graze like cattle on the park’s open lawns. The lawns also provide an ideal runway for takeoffs and landings.
The Park District teamed up last month with Wild Goose Chase, a private agency specializing in wildlife management, to reduce the goose population across the city.
The company has federal clearance to coat eggs with corn oil, which cuts off the embryo’s air supply. The mother goose continues to sit on the oiled egg until she eventually realizes that it will never hatch. Kubat said Wild Goose Chase treated 1,258 eggs in 12 Chicago parks last year.
Susan Hagberg, president of Wild Goose Chase, said an alternative method is to simply shake the egg, but that can be tiring.
She said geese can lay about six eggs per nest, each of which has about a 95 percent success rate of survival. Geese mate for life.
Adam Schwerner, director of the Department of Natural Resources for the Park District, blames part of the goose boom on hand feeding. “A big problem is that people think that [geese] are fun,” he said. “But they are not. Please give us a break.”
Schwerner said the Park District has tried many approaches to discourage the defecators, some with limited success. The district ran trials with border collies to harass geese and push them out.
“[The geese] just pick up and go to another place, where it is a problem again,” Schwerner said.
Park officials have also tried spraying grass with a digestive irritant that gives geese nausea within 20 minutes. The spray, they say, does not affect humans.
The chemical also causes geese to see black dots in the grass. Geese view light in the UV spectrum, while humans only see in the visible spectrum. What looks like healthy grass to humans can look speckled and unnatural to geese.
Schwerner said the problem is that rain washes away the chemical.
Web sites for wildlife management consultants advertise an elaborate menu of additional deterrents, including remote-control boats and plastic owl decoys. One device, a riding vacuum, sucks up goose droppings and is available online for about $20,000 from one manufacturer.
Tensions between geese and humans go far beyond the city limits of Chicago.
The U.S. Department of Agriculture euthanized geese in both Florida and Washington state last summer, using carbon dioxide gas.
In 2005, the USDA captured more than 100 geese in Horicon, Wis., a small city 50 miles northwest of Milwaukee. Adult geese were slaughtered and processed for food pantries. Meat from juveniles was donated to zoos to feed big cats and other animals.
Maggie Brasted, an official from the Humane Society of the United States, said her organization discourages such round-ups. “We would rather [parks] chose the route of treating eggs than killing adult geese,” she said. “[Treating the eggs] is a humane option when it is done early in incubation.”
Given the widespread labeling of Canada geese as a nuisance, it is easy to overlook that some subspecies were nearly extinct in the ’60s.
“It is an amazing accomplishment to have this problem,” O’Neill said of the bird’s resurgence.