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Field & Street

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I have always envied dogs their noses. Imagine being able to walk into a room and instantly know not only who was there but who just left.

When I was a kid reading stories about mountain men and cowboys and Indians, the expert trackers were the people I admired most. The stories usually had at least one guy who could look at a patch of bare rock and tell you that six men had walked across it less than an hour ago, that two of the men were left-handed, and that one had a slight astigmatism. To be able to observe and interpret subtle signs seemed a wonderful gift. Other kids wanted to be the fastest gun alive; I just wanted to follow a trail.

Tracking wasn't a very real ambition for somebody growing up in the Chicago suburbs. Generations had trod over every square inch of land around my neighborhood. In the books I read, expert trackers from the Cheyenne or the Comanche would notice a broken blade of grass and instantly know that whatever, or whomever, they were after had just passed by. Around my house broken blades of grass were all over the place, and they might record nothing more than the passing of a Com Ed maintenance truck.

So I grew up with very little tracking ability. I do notice the hoofprints of deer in muddy paths or the webbed prints of gull feet on Montrose Beach, but that's about it.

Except when it snows. In freshly fallen snow, snow that has not yet been subjected to thawing and refreezing, snow that has not yet been blown about by the wind, even unskilled trackers can learn a lot about the movements of animals we seldom see.

Deer tracks are the best place to start. The tracks are big and obvious, and since the white-tailed deer is the only wild hoofed animal in northeastern Illinois, it is impossible to confuse deer tracks with anything else.

In dry, powdery snow you'll probably see only the heart-shaped outline of the hoof. Wet snow holds an impression better, so you should see separate marks for each toe. (I should be more accurate here. The hooves of a deer are not toes, but toenails.)

On average the hooves of adult deer range from about two to three inches long. The larger hoofprints probably belong to bucks, the smaller ones to does. Very tiny prints would be fawns, but there won't be any of those around until this year's cohort is born in late winter or early spring.

Tracks can also tell you how fast an animal was moving. A bounding deer has a stride of six feet or more. Each set of legs moves as a unit, so the two front hoofprints will be more or less side by side, and the rear hoofprints will register in a similar way. The rear prints are ahead of the fore. Like many four-legged animals--dogs and cats among them--running deer put their forelegs down and then swing their hind legs past them at each stride. Walking deer tend to drag their feet. You will notice a trough in the snow behind each hoofprint. The trough is dug by the foot as it swings forward with the stride.

Deer beds are easy to find in snow. They are circular or oval depressions where the snow is packed hard by the weight of the animal's body. If the snow cooperates, you can follow a deer from the moment it arises from its bed. Keep your eyes open as you track it and you should be able to see what it is eating.

Deer are browsers rather than grazers. In winter they eat mainly the twigs and dormant buds of woody plants. Rabbits go after similar food, but rabbits snip the tips off twigs very neatly. Deer do not have upper incisors, so the tips of twigs they have eaten are raggedy. From the look of them, you would say the deer bit about halfway through the twig with its lower incisors and then pulled upward, leaving a stub an inch or two long above the point where the lower incisors cut.

Deer find food from ground level up to a height of four or five feet. In woods with heavy deer populations a browse line can form at that height, an easily visible mark below which every bit of deer food has been eaten.

It occurs to me that I ought to explain a little about how mammals get around. As I mentioned, the prints of deer are made by their toenails, not by their toes. The hooves of all hoofed animals are really enormously enlarged and thickened nails. This is why a good blacksmith can shoe a horse while causing the animal no more distress than you and I feel when we clip our fingernails. Animals that walk on their nails are called unguligrade.

Dogs, cats, and many other carnivores are digitigrade; they walk on the tips of their toes. Humans, bears, raccoons, and other comparatively slow-footed creatures are plantigrade; we walk on the bottoms of our feet.

Tracking gets complicated when you try to identify some of our local digitigrade animals. For example, we have three species of wild canids in northeastern Illinois. Red foxes are widespread and common, gray foxes are scattered and rare, and, as you know if you have been reading the papers, coyotes are around in growing numbers.

The footprints of all three animals are quite similar. They show four toes, each with a pad, forming an arc around the front of a single, large central pad. In a clear print the blunt claws are likely to register. Red fox and coyote feet are about two and a half inches long, while gray fox feet are close to one and a half inches. In a clear print you may see a distinctive ridge crossing the central pad of a red fox.

The problem with identifying these tracks is dogs. We have dogs in all sizes, from smaller than a gray fox to bigger than a wolf. There are ways to tell coyote and fox tracks from dog tracks, but I am not a good enough tracker to do it--and I probably couldn't explain the process in the space of this column even if I were.

The secrets have to do not only with the precise shape of the foot but also with the characteristic gaits. Watch a dog walking or trotting toward you and you will see that it walks sideways. Foxes move somewhat more straight ahead.

There are also behavioral clues that you can use. A dog out for a walk with its owner is interested mainly in having a good time. It will run for no reason at all. It will charge directly into snowbanks. Wild animals don't act like that. They proceed cautiously. They run only when they have to. They don't waste energy plowing through snow if they can find a way to avoid the deep places. Of course stray dogs, dogs on their own, will adopt the ways of the wild if they live long enough to learn them.

The other digitigrade animal tracks you may encounter on a walk through a forest preserve belong to the family called mustelids: weasels, minks, otters, and others. Weasel and mink tracks can be told immediately from those of any canid because they have five toes instead of four. Skunks, which are also mustelids, put their whole hind foot down with each step, but they are digitigrade with their front paws. However, skunks spend the winter asleep in a den, so you won't often find their little footprints in the snow.

Squirrels bound along putting their large five-toed hind feet down flat somewhat ahead of their smaller four-toed front feet. Of course, the fact that the tracks always start and end at the base of a tree is a further clue.

Cottontail rabbits are easy. The footprints of a bounding rabbit are roughly Y-shaped. The small front feet are put down one in front of the other. One is at the bottom of the Y, the other is at the fork. The large rear feet are at the tips of the fork. Twigs eaten by cottontails are nibbled by many tiny bites into a blunt point.

Raccoons leave prints that look almost like the palm print of a very small person, with five long toes extending out of a flat foot. Opossums have five toes too, but on their hind feet three of the toes point forward, the baby toe points outward, and a large thumblike big toe points inward or even backward. No other local mammal has a foot like that.

Sometimes when the snow is just right, you can follow the tiny tracks of a deer mouse or a vole. These little creatures don't spend any more time than is absolutely necessary out on top of the snow. Once in a great while, if you get really lucky, you can see why. You might find the spot where a mouse's tracks have met the tracks of a weasel or fox. Or you might see the broad disturbance in the snow created by the wings of a great horned owl as it settled over a hapless mouse. Reading signs of what happened before you arrived is like having a nose as good as a dog's.

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