By Jerry Sullivan
Coyotes are turning up everywhere these days. A report from the northwest suburbs blames a coyote for breaking the neck of a shih tzu. Not long ago Don Coyote turned up in an editorial in the Tribune, where he was incorrectly identified as canine latrans rather than Canis latrans. But the tone of the editorial was welcoming, seeing this addition to the local fauna as a contribution to the variety of the metropolis rather than a menace to our way of life.
We might as well accept coyotes, since centuries of attempts to destroy them have been absolute--and expensive--failures. Many states are still paying bounties for coyote corpses.
The practice of encouraging citizens to kill animals considered destructive goes way back. As Americans moved out of the eastern forests and onto the prairies, their attention shifted from the timber wolves of the east to the smaller "brush wolves" of the plains. Iowa had a $2 bounty on coyotes as early as 1795--long before there was an Iowa. To collect you had to find a territorial judge and give him the head of the animal you'd killed. Over the years bounties have been so successful at encouraging the slaughter of annoying animals that local governments have often had to suspend them because they were emptying the treasury.
Coyotes have been shot by hunters on foot, on horses, in Jeeps, in helicopters. They have been trapped in countless ingenious and painful ways, poisoned, even dynamited out of their dens. And they have responded to this persecution by remaining plentiful everywhere, even expanding their range by several hundred thousand square miles. Once they were uncommon east of the Mississippi. Now they roam the forests of Maine.
It is instructive to think about why our anticoyote efforts were a total failure while our antiwolf campaign was so effective. Wolves were eliminated from the entire lower 48 with the exception of northern Minnesota, Isle Royale, and a few locations in Wisconsin. We even exterminated them in wilderness areas such as Yellowstone National Park. Relevant differences between the two species are physical--a significant size difference--and behavioral. Wolves are highly social. Coyotes tend to be solitary. Wolves require very large territories; a pack may roam across 100 square miles. Coyotes can get by on a few thousand acres, at times even less. One study in Los Angeles suggested that a lone coyote could get by on as little as 200 acres. Wolves concentrate on large mammals--deer, elk, moose, bison. Coyotes eat mostly rabbits. It seems likely that coyotes could be both more abundant and less obtrusive than their larger cousins.
When a new predator arrives on the scene the effects of its presence are likely to be felt throughout the ecosystem. To learn what those effects are likely to be we need to study the animal's habits, starting with what it eats. The Coyote Project is addressing just that question in the Chicago area. The project was started by a man named Wiley Buck, who's working on a master's degree in wildlife conservation from the University of Minnesota. His thesis topic is the diet of coyotes in the metropolitan area.
There are essentially two ways to study the eating habits of any wild animal. One is to shoot large numbers of them and examine the contents of their stomachs. The other is to collect their droppings. Buck is using the latter method, with the help of a group of volunteer collectors who are checking selected natural areas every couple of weeks. Coyotes use their droppings as territorial markers, so they tend to leave them in conspicuous places. Trails are the places to look, especially high places along trails. Presumably scent carries better from such places than from lower ground.
The usual practice is to take only a part of the scat. Coyotes might get nervous and move on if somebody were consistently stealing their boundary markers. You pick it up with a plastic bag, take it home, and put it in the freezer. Eventually you pass it along to Buck, who stores it in his freezer until he is ready to analyze it.
At this point you may be asking yourself how somebody would go about gathering a group of volunteers to collect coyote doo-doo. Here in Chicagoland we have a ready answer to that question. The Volunteer Stewardship Network is an organization that involves thousands of people in the metropolitan area in the work of ecological restoration and management in county forest preserves and other natural lands. It is jointly sponsored by the Nature Conservancy, the county forest-preserve districts, and the state Department of Natural Resources. People in the VSN are connected by newsletters, work days, meetings, and other activities, so any call for help will reach a large number of potential assistants. VSN members are also people who spend a lot of time in forest preserves and have a large interest in what is happening in our natural areas.
So Buck sent out the call through the various tendrils of the VSN and found himself directing scat collectors from all over the metropolitan area. One of these volunteers, Phyllis Shulte of Mokena in Will County, spends most of her time working for an auto dealer. But off the job she is costeward of a place called the Hickory Creek Barrens. At this point she is the champion scat collector of the Coyote Project, having delivered samples of more than 50 Canis latrans bowel movements. Hickory Creek gets heavy (illegal) use by off-road vehicles and snowmobiles, and she credits her success to the way the heavy traffic keeps down the vegetation.
After a year of collecting she still has not seen any coyotes at Hickory Creek. Her only sighting came recently when she was driving to work very early one morning. She saw two animals crossing U.S. 45 near 145th Street. "I think they were going to the Orland Square Mall," she says. Maybe they were hunting mall rats.
Rose Golembieski works for Allstate Insurance in Northbrook between expeditions to Somme Woods to survey for coyote droppings. A few weeks ago, after a year of collecting numerous samples, she saw her first live animal. "I was walking through the woods, and I looked behind me--and there it was. I guess it saw me at the same time I saw it. We both froze for a moment. I tried to raise my camera to my eye, and the coyote took off."
Analyzing coyote droppings is a complex, time-consuming, and not altogether pleasant business. Buck begins by weighing the samples. Then he puts each sample in a separate porous nylon bag and puts the bags into a washing machine. Twice through on the gentle cycle removes most--but not all--of the smelly stuff. What is left is mainly hair, feathers, and bones. The bones are usually parts of small animals--vole skulls and such--that can be identified. Hair shafts have distinctive scale patterns that can be seen under a microscope and identified.
He measures two aspects of food preference: volume and occurrence. Occurrence tells you how many coyotes are eating the animal in question and how often they eat it. Volume tells how much of their diet consists of that animal. The two numbers may differ widely. For example, many coyotes eat insects in summer, so grasshopper remains and beetle carapaces turn up in lots of scat, but they make up a very small amount of the total food intake of individual coyotes.
No matter how you measure it, our local coyotes are eating more rabbits than anything else. Cottontail remains account for about two-thirds of the volume of the scat, and they occur in about the same number of samples. A survey of coyote stomachs done in Iowa two decades ago also found cottontails to be the largest food item. The Iowa coyotes ate lots of domestic animals--including sheep, cattle, pigs, and chickens--and these formed the second largest category of their diet. Scientists tend to think that much of the domestic-animal intake is carrion. Farmers tend to disagree. Still, the Iowa study found that wild dogs accounted for more livestock losses in the state than coyotes.
Metropolitan coyotes don't have access to many farm animals. Buck's results show deer to be the second most popular item around here. Deer remains amounted to about 15 percent by volume and about 28 percent by occurrence. Thus far Buck has not analyzed his data sufficiently to see if there is seasonal variation in deer eating. Rose Golembieski found a half-eaten fawn at Somme Woods, and it may be that young or injured animals are the main targets of the coyotes. However, there is evidence that coyotes have learned to trap deer in fence corners. It would probably take more than one coyote to bring down a healthy whitetail. Coyotes don't average much more than 30 pounds each, though they look a lot bigger when you see them in the woods. The hunters could have been a mother and her nearly grown pups. Raccoons, voles, birds, and squirrels--in that order--account for most of the rest of the diet of local coyotes.
The effect of this new predator won't be known for decades. Ecological time operates in longer rhythms than human time. But thanks to Wiley Buck and his volunteers we are getting in on the beginning of the story.