The City Raccoon and
the Country Raccoon By Jill Riddell

I'm striding down Fifty-seventh Street in Chicago's Hyde Park when a mammal pops out onto the sidewalk in front of me. It's dusk, and my vision isn't perfect, so at first I try to make the mammal familiar — an overweight cocker spaniel, or a rotund cat, perhaps. But when streetlight illuminates a faintly striped tail, I realize the animal is a raccoon. As we reach the front of a yellow house, the raccoon makes a right turn. The gate is shut, but the raccoon clambers over the fence and disappears into the shadows of a well-landscaped yard. Never once does it glance at me, a much larger mammal only a few feet behind.

	Feasting on fries in a garbage can. City raccoons wouldn't know what to do in a forest preserve. Photo by Pam Breitberg.

Raccoons are in that small cadre of mammals that human beings haven't managed to scare off from living near us. Rabbits, squirrels and a few other animals have found we're not all bad as neighbors go, though like the raccoon I saw, they prefer to coexist rather than interact with us. For these animals, the habitat we create in urban neighborhoods isn't terrible (as it would be for a buffalo, for example) and the eating is pretty good. But city living is not risk-free for raccoons. Cars are a hazard, the number-one killer of raccoons (disease is number two). And if a raccoon picks a den site in a spot humans don't approve of, the coon and its entire family may be removed and euthanized. (Pest control services are no longer permitted to relocate city raccoons to forest preserves.)

And while I have pointed out the hefty proportions of this raccoon — mature males can reach thirty pounds in the fall — I must also understand that I, too, might choose to put on a few pounds if I knew that soon I would be starving for several months straight. Raccoons don't hibernate, but they do spend many weeks in a dormant state in winter, burning fat reserves and waiting for the occasional snow-free, mild-temperature evening when they might be able to come out and forage.

Stan Gehrt, a wildlife biologist at Max McGraw Wildlife Foundation in Dundee, reminds me of this fact when we meet to discuss how raccoons are faring in the Chicago region. For seventeen years, Gehrt has been studying raccoons in Kansas, Texas, and most recently, northeastern Illinois.

In 1995, he launched what started out as a two-to-three-year study on raccoon populations within the Chicago metropolitan region. He studied three sites: Busse Woods, which is a Cook County forest preserve completely surrounded by highways, densely developed residential neighborhoods and industrial sites; Max McGraw Wildlife Foundation's property, which is surrounded by suburban development; and Glacial Park in McHenry County, where the surrounding land usage is more rural in character. Seven years later, the study continues to focus on raccoon population dynamics, accounting for factors such as density, survival, mortality, age, sex and reproductive success. To date, Gehrt and his team have marked more than 1,300 raccoons with ear tags and 250 with radio collars. Biologists have also taken blood and fecal samples from captured raccoons to monitor the presence and distribution of disease.

Rocky and Bambi at home in the woods. Photo by Eric Fogleman.

A number of interesting findings have come from the study. For instance, people previously believed that as raccoon population density increased inside a forest preserve like Busse Woods, raccoons would be forced to leave the woods and establish homes in surrounding neighborhoods. This turned out not to be the case. Instead, for the most part radio-collared raccoons didn't even travel around the entire forest preserve; their territories are quite small within the preserve, and though they might venture a few blocks into the subdivisions, none of the study animals left for good and built dens.

This doesn't mean there are no raccoons living in those neighborhoods. Rather, it suggests that raccoons raised in a forest preserve tend to remain in that preserve, while raccoons born inside the urban matrix will likely continue to reside in the city or suburban neighborhood they are familiar with. Rather than leaving Busse Woods, the raccoons adopt smaller home ranges and allow other raccoons to occupy the same range.

Another surprise was how seldom raccoons disturbed the eggs of ground nesting birds. Scientists had been concerned about the impact of raccoon predation on other species, so in the third year of the study at Busse Woods they constructed four hundred nests, each containing real quail eggs and one plasticene imposter that, when bitten, retained the teeth imprint of the predator. Raccoons located about 15 percent of the false nests, a rate lower than in surveys conducted in more rural areas. Gehrt says this may be due to urban raccoons' reliance on human garbage.

Radio telemetry of the collared raccoons showed that raccoons tend to take a direct path between their den and picnic areas. "The raccoons in Busse Woods aren't spending a lot of time foraging on the ground," says Gehrt. "While the artificial resources brought in by people result in an abnormally high raccoon population, the presence of the garbage may actually reduce the impact of raccoons on some species."

However, Gehrt adds that there is anecdotal evidence suggesting that raccoons may affect frogs and other amphibians and reptiles more than they affect birds. Eggs don't appear in bird nests until the weather is quite warm, but frogs show up in early spring when raccoons are still ravenous from the long winter. And when frogs begin to sing, mate, and lay eggs, picnickers bringing food have not yet appeared in the preserves, so raccoons rely more on natural food sources. Since the raccoon population is so large (raccoon populations in urbanized, highly developed areas are roughly four to twelve times greater than those in rural locations), prey species may be hit harder than they would be in a more natural situation. No study on amphibians and reptiles has yet been conducted to confirm this theory though.

Along with their more serious findings, researchers also made some lighter discoveries. They observed that some raccoons, especially females, become "trap-phobic" and are extremely difficult to trap a second time, but other raccoons become "trap-o-philes," going willingly into the traps over and over again. Sometimes Gehrt would find a repeatedly-caught male comfortably asleep in a trap — and it wouldn't have even bothered to finish eating all the bait food.

Gehrt's team also found that French fries caused the biggest food fights among raccoons. Perhaps most telling of all, the observers spent the better part of one evening watching a raccoon walk around with a Dunkin' Donuts bag on its head.

Yet for all that the study has uncovered over seven years — a long time for wildlife surveys, which often run out of funding before they can track trends for anywhere near that length of time — Gehrt is careful to say that there is much he still doesn't know about raccoons.

He points to the variety of individual characteristics he has observed among raccoons. While many raccoons may follow a certain pattern of behavior, and it is useful to understand such patterns, Gehrt says, "typically you'll find 10 to 15 percent that will do the opposite." He also says, "People call me an expert, but one thing I've learned from working with raccoons for so long is, I'm not an expert."

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For tips on discouraging raccoons from coming to live with you, check out the Kildeer Countryside Virtual Wetlands Preserve at www.twingroves.district96.k12.il.us/Wetlands/WatchTower/NWRaccoons.html.