Mud, Glorious Mud!

Unlike many people I know, I’m always sad to see the snow disappear for good. But as soon as I think of what comes next–mud season–I get excited all over again. The transition between the seasons is highlighted in the photo below. A gray fox had stepped in some mud and then left it’s muddy footprints on the snow as it walked from left to right. Each deposit of mud is made by first the front and then the rear feet from the same side, and the zig-zag pattern of the walk shows nicely.

Once the snow is gone, ordinary mud takes its place as a medium for recording tracks. In the next photo an opossum stepped in some mud at the edge of a puddle, leaving a collection of both complete and partially obscured prints oriented toward the left. At the upper left there’s a right front track with a right rear track just behind it. Farther to the right you can see part of another right front track. In the lower right corner there’s a nearly complete left front print and just the suggestion of a left rear behind it. The front prints show the five widely spread toes that are characteristic of the opossum. In the front print at the upper left the segments of the semicircular middle pad are especially clear. The rear track in the upper center shows the strikingly different form of the opossum’s rear foot: a thumb-like inner toe pointing inward and four additional toes close together and pointing outward.

One of the nice things about mud is that it can record the presence of animals that we don’t encounter during the cold season. A spotted salamander (or maybe two of them) walked through the mud in the next photo. These amphibians hibernate in winter and come out in early spring, so mud season is a good time to look for their tacks. There are two trips: one going from the left side toward the upper right and the other proceeding from left to right along the lower part of the frame. Each trail consists of a central drag mark made by the tail and a sequence of front and rear prints on each side. The patterns of the prints tell us that the animal(s) were moving at an understep walk, with each rear foot touching down just behind the front foot from the same side. In the lower trail you can see the difference between the smaller, four-toed front prints and the larger, five-toed hind ones.

The tracks in the preceding photos are pretty obvious, but it’s not always easy to spot tracks in mud. In the photo below there’s a patch of shiny mud in the center of the shot, and on the right side of that patch there are some tire tread marks. If you look on the left side of the same shiny mud toward the top you’ll see a red fox track. The animal was moving from top to bottom, and because there weren’t many muddy spots the print in the photo was the only one I could find.

The close-up below shows the same track, but in this view it’s oriented in the opposite direction, toward the top. The central mound typical of canine tracks can be seen, and the marks made by the hair on the underside of the foot show clearly. There’s even a partial impression of the bar in the middle pad.

Woodchucks, like salamanders, spend the winter below ground and often emerge just as mud season is beginning. The next photo shows the left rear track of a woodchuck at the upper left and a left front track at the lower right. The five clawed toes of the rear print show clearly–the middle three toes set close together and the inner and outer toes angled toward the sides. Behind the toes you can see the four segments that make up the middle pad. In the front track the four toes with their substantial claws can be seen. The subdivided middle pad of the front foot lies behind the toes, and the heel pads show as two depressions behind the middle pad. The front print has a curvature toward the inside, a trait typical of the woodchuck.

It takes a medium with a fine texture to show details of the tracks of very small animals, and what better medium than mud? In the photo below you see the tracks of a white-footed mouse bounding from lower left to upper right. The tracks are arranged in the typical rodent bounding pattern–two rear prints (in the upper right quadrant) that are widely set and almost even with each other. Behind the rear tracks, the front prints are set more narrowly and, in this case, slightly staggered rather than even with each other. Track details show beautifully, especially in the left rear (the topmost track) and the left front (farthest to the left). If we compare these tracks with the woodchuck tracks above we see the rodent family resemblance, especially in the rear prints. The symmetrical mouse front tracks are more typical of other small rodents than the curved front prints of the woodchuck.

You can’t ask for a better rendition of detail than the porcupine tracks in the next photo. Porcupines have unique foot anatomy: their tough, undivided soles have a pebble-like texture that gives the animals good grip when climbing. The photo shows a left front print and, just behind it and overlapping slightly, a left rear print. The tracks are heading toward the left, and the texture of the soles shows beautifully. Because the leading edge of the rear foot touches the trailing edge of the front track, the two tracks seem to be joined together. You may be able to pick out the claw marks of the hind print along the leading edge of the sole of the front print. The four claws of the front foot made indentations at the very left, and if you look closely there are marks made by the three outer phalanges of the front foot behind the claw marks.

Once the snow melts and the weather warms, mud may not last long. Puddles may dry up and wet areas may fill in with plant growth. But mud can also appear in new places, and abundant rainfall can bring on new mud seasons long after the early one is over. As a matter of fact, I found the porcupine tracks in the photo above in the month of July. So keep an eye on the conditions of the puddles in your neighborhood, and don’t be surprised if you come across some beautiful mud when you least expect it.

Canine Romance

It may seem like the wild creatures are all hunkered down, just doing their best to stay alive and wait out the cold season. But for wild canines there’s more going on than simple survival. This is mating season for foxes and coyotes, and they’re engaging in behaviors that will eventually lead to reproduction. For human trackers the first clue to their new fixation is the increasing frequency of scent marking. In the photo below you see a splash of urine on the snow to the right of the corn stalk, left as a message to others of its kind by a gray fox.

Urine contains complicated combinations of chemicals that, to a discerning canid, reveal the identity and health status of the animal that produced it. As mating season progresses, changes in the chemical signature also indicate the animal’s readiness for mating and reproduction. Most of these messages are too subtle to be detected by people, but fox urine is an exception. The urine of both red and gray foxes takes on an increasingly musky, skunk-like odor as hormonal changes progress, and in late winter this odor is strong enough for a person to detect it a good distance away from the deposit.

The fox whose scent mark is seen in the image above was walking from the upper left to the lower right. We know that the it was a male because of the placement of the urine off to the side of the animal’s trail. The direction of travel is revealed by the appearance of the snow around the edges of the tracks. When a foot goes down into snow it pushes any movable material down into the hole. When the foot comes up and out again it often brings a little snow up with it, and this snow is dropped around the leading edge of the track as the foot moves forward above the surface. This means that the snow around the entry end of a track is relatively undisturbed while the surface at the exit end is decorated with sprays or scatterings of snow. In the photo of the gray fox trail there are four deep tracks, each one the landing place of a front and a rear from the same side, plus a light track near the third deep track. Starting at the upper left (and considering just the deep tracks), the sequence is left front + rear, right front + rear, left front + rear, right front + rear. The animal was standing on its right hind foot when it lifted its left hind leg to squirt urine at the corn stalk. The shallow print was probably made as the fox placed its right front foot lightly on the snow for balance while it was urinating. The corn stalk was a convenient object, but rocks, clumps of weeds, branches, or anything else that protruded above the snow would have done as well.

Among coyotes and foxes, early winter is the time for the establishment or reestablishment of pair bonds. Those that spent time apart after they raised a litter in the previous season usually rejoin, and unattached animals roam widely in search of potential mates. Bonded pairs establish their territory by scent marking around the edges, especially along borders shared with others of their species. Unless we are familiar with the area and the animals involved it’s hard to know whether scent marks are advertisements of availability or warnings that the territory is occupied.

During the lead-up to mating, pairs often travel together. The trails in the photo below were made by two red foxes travelling along a forest road. For at least half a mile the two trails wove back and forth, occasionally changing speed and sometimes diverging, but always coming back together. The male, with slightly larger tracks, enters the frame at a gallop, moving from the lower left to the upper right. The female is doing a side trot and her trail comes in at the lower right and leaves at the top of the frame just to the left of the male’s trail.

All of the behaviors I’ve described above help to strengthen the pair bond and propel the hormonal changes that lead up to mating. When the female’s endometrial lining begins to develop, her urine contains blood, and she leaves scent marks like the one in the photo below. She’ll soon go into heat and only then will she be receptive to the male’s advances.

The pair are both involved in the process of den selection and preparation, and pups are born about 50 (foxes) or 60 days (coyotes) after successful coupling. By initiating the early stages in the dead of winter nature insures that the pups are born in the spring when food will become increasingly abundant. Note: It’s important for trackers to avoid disturbing animals during this vulnerable time. We should not approach too closely or otherwise disturb a den site starting with the period of den preparation and continuing until the pups are no longer dependent on the den for safety.

This is, by the way, why coyote-dog hybrids aren’t as numerous as some people believe. Over thousands of years of domestication, dogs have lost the finely tuned sequence of reproductive behaviors that occurs in wild canines. Mating in dogs is no longer synchronized with the seasons, and males don’t assist in the raising of pups. Since these behaviors are genetically controlled, the offspring of matings between dogs and coyotes have disrupted patterns of behavior. The precise timing of reproduction is lost, as well as the strong pair-bonding and the dual effort from both parents (and sometimes female offspring from the previous year). For this reason the offspring of matings involving dog-coyote hybrids are unlikely to survive.

This is a great time of year to let tracking open a window into some of the underlying processes of the natural world. The mating rituals of wild canines have been shaped for success by natural selection, and this is beautifully illustrated in the behaviors we see in the tracks and trails of foxes and coyote.

Checking Out Fox Dens

It’s late summer, and fox pups that started life back in late March or early April as small, helpless balls of fluff have grown into sleek coated adolescents. At about five weeks they emerged from the den, and for the next month or so they spent their time near the burrow, developing their strength and coordination through play and mock fighting. They were guarded by parents or females from the previous year’s litter, and at the first sign of danger they dashed to safety below ground. Later they began to accompany their parents on explorations and hunting forays. But even when the kits were quite mobile, the family may have continued to rely on the den as an emergency refuge. I don’t like to disturb fox families until they no longer need that safe haven, so I always wait until late summer or fall before I investigate a fox den.

Fox dens are found in settings ranging from dense cover to open, exposed areas. The den in the photo above was near a house and driveway, but it was well concealed by shrubby cover and wasn’t obvious until I got up close. In the next photo you see the other extreme–a den dug under an old pallet that was located near a highway intersection and lacked any concealing cover. Both of these are red fox dens.

A closer shot of the den in the photo above shows several entrance holes, a throw mound (at the lower right), and tracks in the loose dirt. These photos were taken during the excavation phase, and by mid-spring the den site–and the antics of the pups–were hidden by a screen of grasses and forbs.

Cemeteries are another popular spot for red fox dens. The one in the photo below was behind a grave stone and shaded by a mulberry tree. The black specks you see scattered on the dirt and grass are mulberries.

The mulberry tree was a handy source of food, and fox scat containing mulberry seeds decorated some of the grave markers.

The next photo shows a gray fox den. There wasn’t any concealing cover around the entrance, but getting to it involved a thirty-minute hike and a climb up a steep slope. Gray fox dens are usually farther from human habitation and harder to get to than red fox dens.

There are other medium-sized mammals that use burrows, and distinguishing among them can be tricky. Tracks or direct observation of the residents are the best clues, but failing that we have to rely on other features. One helpful characteristic is the size of the entrance hole: fox dens normally have openings between 6 and 12 inches across, while coyote dens can be twice that. (And like gray fox dens, coyote burrows are not generally found in places with a lot of human activity.) Woodchuck dens have entry hole sizes on the small end of the fox range and can be difficult to separate from fox dens. The most striking difference between the two is the condition of the soil around the entrance. Woodchucks use dens throughout the growing season, and the throw mound, a spreading apron of fresh dirt like the one in the photo below, shows signs of disturbance as long as the resident is active. But unlike fox dens, woodchuck dens show little disturbance of the surrounding soil. These summer lodgings may be abandoned for burrows in more sheltered areas when it’s time for hibernation, and once that happens the soil near the summer den loses its disturbed look.

Fox dens can also have throw mounds (as in the third photo), but they usually have a more trampled look due to the comings and goings of the parents. Once the kits emerge and begin playing, their antics create an area of flattened soil and plant growth much larger than the original disturbance. Active fox dens may also have scat and the bones of small animals nearby. Occasionally, as in the photo below (also in a cemetery), other kinds of toys show what the pups have been playing with.

By the time fall comes the young foxes no longer need an underground refuge, and the area around the den becomes weathered and undisturbed. Unused dens are difficult to assign to an owner and may, in fact, have different residents in the next birthing season. During the winter foxes begin to investigate den sites, and an alert tracker may notice the telltale tracks of a pair of foxes making frequent trips to certain locations. Once the snow is gone favored sites show signs of activity like those shown in the second and third photos.

Separating Felines and Canines

Cats and dogs–they live among us as companion animals, and their wild relatives are a familiar presence in our landscapes. The two groups differ from most other mammals in having four toes on both front and back feet, and in both groups there’s a smooth pad (the middle pad) behind the toes. So how to tell them apart? One thing we often hear is that canine tracks show claws and feline tracks don’t, but the presence or absence of claws can’t always be relied on. Cats can extend their claws if they need more grip, and the claws of wild canines may not touch the ground because they are naturally trimmed by constant movement. Fortunately there are other features that can help us to distinguish between canines and felines. It’s a simple matter of paying attention to details, and there are plenty of them. So let’s get started.

In the photo below you see the front track of a coyote, direction of travel from bottom to top. The overall shape is elongated, the toes are relatively large compared to the middle pad, and the outer toes are tucked tightly behind the leading toes. The middle pad has a pointed forward edge. Roughly in the center, between the toes and the middle pad, there’s a dome-like area, and an X is formed by the ridges between the middle pad, the outer toes, and the two leading toes taken together. The dome and the X are the negative spaces, areas that are not pressed down by toes or pads, and their arrangement is an unmistakable indicator for members of the dog family. (By the way, note that there are no claw marks.) And another important detail: the track is symmetrical. By symmetrical I mean that the right half is almost identical to the left half.

Here’s a way to grasp the concept of symmetry. In the next illustration I’ve added a vertical line which bisects the track. If you imagine folding the right half over along the line so it lies on top of the left half, the two halves will match almost exactly. The two leading toes are almost even with each other, the inner and outer toes are of similar size and spacing, and the middle pad seems to point straight ahead.

Now let’s compare a feline print. The photo below shows the front track of a bobcat. The overall shape is more rounded, the toes are relatively small compared to the middle pad, and they’re arranged in a wide arc in front of the middle pad. The left-most toe is smaller and farther back than the others. There’s no central dome, and the ridge between the middle pad and the toes is broadly curved or C shaped. Rather than pointing straight ahead, the middle pad is canted to the left. The arrangement of toes and middle pad makes the track very asymmetrical.

To get at the asymmetry here’s the same photo with a vertical line bisecting the track. If you do the mental experiment of folding one side over onto the other as we did with the coyote print, you’ll see that the two halves don’t match. One toe leads all the others, and the smallest one lags behind the other three. The whole print seems to be canted to one side. Because it’s asymmetrical we can tell which front print this is–it’s the left. If we were looking at an isolated coyote track it wouldn’t be possible to know if it was a left or a right.

Here’s the front print of another canine, a red fox. It’s not as elongated as the coyote print, but the overall shape is still more oval than round, and the outer toes are tucked in behind the leading toes. The central dome and canine X are unmistakable, and the track is beautifully symmetrical. In this case claw imprints show as delicate punctures directly ahead of the toes. The mud was just moist enough to show the hair on the underside of the foot and the chevron in the middle pad perfectly.

Perhaps you’re thinking that I oriented the bobcat track incorrectly, and that if it were rotated a little it could be made to look more symmetrical. But the asymmetry is inescapable, no matter how you look at it. In fact, when an animal is moving at a steady gait the correct orientation of each print is dictated by the direction of travel, and the imaginary bisecting line should be parallel to the direction of travel. The next photo shows part of a sequence of tracks made by a house cat moving at an overstep walk, a gait in which the rear print lies ahead of the front print from the same side. The direction of travel is from lower right to upper left.

In the next illustration I’ve added a line which defines the direction of travel to the same photo. (Sorry about the slight wobble, just imagine it’s really straight.) With the line as a reference, you can see that each track is canted to the outside. Also notable in this photo are the shapes of the middle pads: wide and blunt on the forward edges and scalloped on the trailing edges. The C-shaped ridges between the middle pads and the toes are especially striking.

The topic of gaits brings up another criterion sometimes said to distinguish canines from felines–direct register versus indirect register. Walking felines are said to place their feet in direct register, so that the back foot comes down exactly on top of the print of the front foot from the same side. Canines are supposed to prefer the indirect register walk, placing the back foot partly, but not exactly, on top of the front from the same side. But this isn’t a make-or-break test. The next three photos illustrate this point: first you see a bobcat direct register walk, next a bobcat indirect register walk, and finally a red fox direct register walk. The fact is that both felines and canines use both direct and indirect register walks. It’s fair to say that domestic dogs and cats are more likely to walk in indirect register than wild canines, but even among wild species there’s variation, and the difference isn’t very useful for identification purposes. And of course it wouldn’t apply in other kinds of walks, such as the overstep walk in the previous illustration.

Bobcat direct register walk
Bobcat indirect register walk
Red fox direct register walk

Our other fox, the gray fox, makes tracks that are a little more catlike. In the photo below you see a rear print, below, and a front print, above. The overall shapes are round enough to be confusing, the central dome and canine X are a little different from the ones shown for the fox and the coyote, and in the hind track there appears to be a leading toe. Gray foxes have semi-retractable claws which don’t usually show in tracks, so the presence of claw marks suggests that the animal needed more stability in the wet mud.

In spite of the variations the tracks are clearly canine. Compare them to the bobcat tracks in the next photo, this time a left rear below and a right front above.

These two photos bring out some potential pitfalls in the task of differentiating canines from felines. Animal feet aren’t rigid, and toes may spread or tighten depending on the animal’s movement and the nature of the substrate. In the gray fox hind print the two leading toes gripped the soil differently, causing one to appear farther ahead than the other. The normal symmetry of canine tracks can be altered by head turns, changes of direction, or by sloping terrain. Another potential source of uncertainty is the fact the hind feet of felines are often more elongated than the front feet. In the bobcat photo above the rear track has a slightly canine appearance due to the tighter arrangement of toes and the more oblong shape.

And lastly, never underestimate the power of domestic dog tracks to create confusion. The track in the next photo was about the size and overall shape of a bobcat print, lacked claw marks, and mimicked the blunt middle pad and C-shaped ridge of a feline. Red flags were raised by the symmetrical structure and the large toes, but it was really the presence of more tracks which clinched the identity as dog. Domestic canines are incredibly variable–their tracks can be quite round and the tendency of the toes and middle pads to spread can give the negative spaces a feline appearance.

So the task of separating canines and felines is not always easy. Isolated prints are harder than more complete sequences, and weathering and distortions can make things difficult. But the more you study them, the better you’ll be at picking out the crucial features. And if one of these creatures is rare in your area, it’s a joy to find it’s tracks and know you’ve made a solid identification.

When the Snow Gets Deep

One of the challenges in a winter like the one we’ve been having is tracking in deep snow. Our native animals are mostly well equipped to cope with such conditions, but the evidence they leave can be mystifying–animals may change their habits, tracks and trails may look very different, and the details we generally rely on for identification may be absent. But the lives of animals are still written in the snow. To read these stories we just need to acquire some new reference images and expand our tracking skills.

A red fox made the trail shown below. In the deep snow the direct register walk was the most energy efficient gait, each hind foot coming down in the hole made by the front foot on the same side. Compared to walks in easier conditions the fox’s steps were shorter and its trail width was greater. The animal lifted its feet cleanly out of the snow, leaving just a few drag marks.

The direction of travel, from bottom to top, is revealed by the sprays of snow which fell off the feet as they rose out of the holes and moved forward. Whether animals are walking or moving at faster gaits–as long as their movements are regular and smooth–snow falling from their feet usually lands ahead of the tracks. Only during sudden acceleration or changes of direction do we see snow pushed backward or to the side.

A coyote walking from left to right made the trail in the next photo. The snow was less consolidated so there’s a softer appearance to the trail. The details in the track floors are obscured by the snow that fell in as the feet were lifted out, and the animal’s feet skimmed the soft surface leaving drag marks. Looking down into the holes (which is always a good idea in this kind of situation) we can see the shapes of the forward edges of the animal’s feet. The overall shape of a coyote’s foot is oval or egg-shaped, but how should we describe just the front half? The best I could come up with is parabolic or bluntly arched. Whether or not there’s a word for it, this shape is characteristic of coyotes and red foxes, and also some dogs. And there’s another feature that is typically canine: in the very tip of the hole on the right you can see two small dents made by the leading claws–a dead giveaway for a red fox or coyote. Gray foxes usually have more rounded leading edges and less tendency to show claw marks. Being shorter legged than red foxes, gray foxes are more likely to leave drag marks, and dogs are also prone to dragging their feet.

These two trails illustrate the general appearance of canine trails in deep snow. Because walks in deep snow tend to be very close to direct register it may be possible to get rough measurements for track widths, and this, plus stride or step length, can help to separate coyotes from red and gray foxes.

Bobcat trails in deep snow may be quite different from canine trails. In the photo below a bobcat walked from bottom to top, and at each step it spread its feet as they went down into the snow, creating a sequence of interlocking triangles. As usual, snow obscured the details of toes and pads at the bottoms of the holes, but in the lowermost impression you can see that the forward edge of the track is widely crescent-shaped rather than parabolic.

Sometimes animals negotiating deep snow move faster, perhaps out of fear or maybe just playful antics. In the photo below a red fox bounded from upper left to lower right, leaving holes where its body went in up to its shoulders. There may not be much information inside the holes, especially if the snow is loose and movable as it was when the photo was taken, but their width provides a rough measure of the width of the animal’s body. The level of effort required for this kind of movement means that it can’t be sustained for long periods, so following the trail either backwards of forward will probably bring you to a change of gait.

In spite of their long legs, deer are not well suited for moving in deep snow. Their feet are small in proportion to their body weight, so they sink in deeply. Deep drag marks like those in the photo below are typical, and sometimes the tips of the toes can be seen at the bottoms of the holes.

In deep snow deer may limit their movements to trails they’ve already made, such as the one in the next photo, where they can move with less effort. If the difficult conditions persist the animals may limit their movements to very restricted areas which become crisscrossed with trails. These deer yards are usually found under conifers, where the snow isn’t as deep and the evergreen foliage traps heat. When deer yard up the available browse is quickly eaten, so they eat very little, reduce their activity, and wait out the winter.

For short-legged animals like porcupines, skunks, and muskrats the only option in deep snow is to bulldoze their way through. In the photo below a skunk struggled from upper left to lower right, its body plowing through the snow and its feet punching deep holes in the bottom of the groove. The small pits made by the feet, combined with the short strides and wide trail width are good indicators of the animal’s identity.

When temperatures fluctuate or sun melts the surface, snow can develop an icy crust. Sometimes this reduces the problem of movement, allowing lighter animals to move easily over the surface. But if the hardness of the crust varies or the animal is just a little too heavy, we may find scenes like the one in the photo below. A coyote attempting to cross a drift found that it wasn’t always supported by the crust. Where it broke through it left crisp outlines of its lower legs and spread toes.

Like other animals, rabbits and squirrels can plunge deeply into snow, and this can make it hard to identify their tracks. But the difference in the positioning of the front feet usually provides a clue to the animal’s identity. The next photo shows a cavity made by a gray squirrel bounding from lower left to upper right. Inside the hole there are two depressions, each one made by a front foot and a rear foot from the same side. The wide separation of the depressions and the equally wide entry and exit disturbances give the hole a boxy or rectangular shape.

Compare that to the next photo of a rabbit in deep snow, also bounding from lower left to upper right. Because the rabbit brought its front feet down on or close to the center line of the trail, the entry point (at the lower left) is narrow. The rear feet made a wide depression in the deepest part of the hole and left separated drag marks coming out. The result is a triangular cavity with the wide end opening toward the direction of travel.

Maybe the biggest hinderance to learning how animals move in deep snow is just getting out into the stuff. You’ll need snowshoes or skis, or at the very least good gaiters, to get close to the tracks. But if you spend some extra time arranging all your gear you’ll be rewarded with a deep look into the lives of animals in deep snow.

A Gallery of Red Fox Tracks

I’m fascinated by track variation. No two tracks are ever exactly alike, even if they were made by the same animal doing the same gait on the same substrate. Sometimes variations within the prints of one species are so extreme that it’s hard to believe that they were made by the same kind of animal. This applies to all creatures, but I think the red fox is a particularly good illustration.

In the photo below you see a front print made by a red fox traveling from left to right. This is a typical track: oval in shape with finely pointed claw marks, and a curved impression–called a bar or chevron–running vertically through the middle pad. A striated texture in the toes and middle pad shows how the fur which covers the underside of the foot pressed into the mud.

The track pictured above also has some features that are found in all of our wild canines. There’s a dome in the center, and the major ridges meet at the dome to form an X shape. The toes are held tightly together and the claw marks point straight ahead.

Here’s another front print made by a red fox, again traveling from left to right but at greater speed. This time the mud was firmer, so the track is shallower and the marks of the hair are lighter. Instead of lying tightly together, the toes are spread and the claws, especially the inner and outer ones, angle outward. The bar in the middle pad is the deepest part of the track, suggesting that the horny protrusion might have served to increase traction.

A fox moving on even firmer mud and at even greater speed made the next example, again traveling from left to right. We see only the claw marks, the tips of the toes, and the middle pad bar. As in the previous photo the toes are spread and the claws angle outward.

Sometimes the fur on the underside of the foot is the most obvious feature of the track. In the next photo, made in wet mud, the direction of travel is from right to left, and the texture of the hair seems to cover the entire track except for the middle pad bar. But take a close look at the areas toward the tips of the toes, especially the two leading toes. There’s a spot in each toe impression that’s deeper and doesn’t have the striated texture. These marks aren’t just accidental artifacts–they’re real (although seldom seen) features of red fox tracks. Each toe has a small, hairless bump near its tip which can protrude through the hair to leave a mark.

There are other anatomical parts which can show up in tracks. The print in the photo below was made in soft sand by a red fox moving from left to right at high speed. The spread toes and deep toe and middle pad bar impressions should be familiar by now, but just behind and above the middle pad there’s an additional mark. This was made by the dew claw, the reduced fifth toe present on the insides of the front feet of most canines. And to the left of that and straight back from the middle pad there’s a shallow indentation made by the carpal pad, a knobby protrusion found higher up on the back of the front leg. This is another feature found on foxes, coyotes, and domestic dogs.

Dewclaws and carpal pads only show in tracks if the lower leg joint (it’s actually the carpal joint) is well flexed or the foot sinks down into the substrate. The print pictured above had some of both–the foot sank into the sand and the galloping gait caused significant flexion in the carpal joint.

I’ve been focusing on tracks in mud and sand because they show track details so beautifully, but snow can be just as revealing. The red fox that made the prints below was traveling from left to right. There’s a nice bar in the middle pad of the front track (at the lower left), and as we expect in the red fox, the rear track (at the upper right) has a smaller middle pad with no bar. The dome and canine X show clearly in both tracks. Small depressions at the tips of the toes of the rear track show where the hairless protrusions (the same ones seen above in the wet mud) pushed deeper into the snow. In dry, fluffy snow like the substrate in the photo below, the fur on the undersides of the feet doesn’t leave distinct marks. Instead it has the effect of blurring the outlines of the toes.

Track variants can be puzzling, but they can also lead to better understanding of foot anatomy and animal movement. So when you’re perplexed by an unusual print take a breath, focus on something different for a moment, and let the pieces of the puzzle fall into place at their own speed. It will be well worth your time.

The Allure of Scent Marking

Deep in the coldest months of winter, when you’d think every animal is single-mindedly focused on survival, some predators are being distracted by an equally compelling urge–mating. Even as the snow flies, time spent hunting decreases and behaviors connected with reproduction become more predominant. For the tracker one of the best signs of this change is an increase in scent marking. I followed a red fox trail recently, and she was detouring to urinate on raised features like this stump every 500 feet or

so. I say she because the arrangement of tracks and the placement of the urine could only have been done by a female fox. In the photo the small spots in the left half of the stump are urine (you can ignore the dark chunk of bark near the center). The fox came in from the lower left, paused on the upper side of the stump to pee, and proceeded towards the upper right. The more deeply impressed track marked SF was made by the supporting rear foot (the left) while the right rear was raised. During mating season red fox urine has a strong, slightly skunky–but not unpleasant–odor that is obvious even to us smell-challenged humans. So as I followed the trail the air was perfumed with fox musk.

My dog Banjo (dogs are great teachers for wild canine behaviors) demonstrates the technique in the photo below, supporting her weight on her right rear foot plus the two front feet and positioning her left rear leg up and forward. You can actually see the urine squirting downward under her rear end.

Male canines also raise a rear leg when they urinate, but the leg is held out and back, and the urine goes out to the side rather than downward. I don’t currently have a male dog so I can’t show you that, but I’m sure you can imagine the posture. A male coyote, traveling from left to right,

made the scent mark above, supporting its weight on the right rear foot (the track at the lower center) and shooting the urine sideways onto the upper part of the stump. Coyote urine has a mild odor and isn’t nearly as detectable by humans as fox urine is.

Bobcats also feel the mating urge in the winter, and again, those who have house cats, especially males, may have observed the technique. A male bobcat left its signature on the log in the photo below, coming in from the top of the frame, depositing its message, and leaving at the lower left.

It first gave the log a good sniff (revealed by the front print facing the log), then turned so its rear was facing the wood and sprayed urine backwards. Here’s the photo again with the tracks marked.

S denotes where the bobcat placed a front foot as it sniffed the log. RH, LH, RF and LF show the four feet in a squared posture as the cat faced away from the log and urinated backwards. Bobcat urine, like house cat urine, has a strong odor of ammonia, so if you had been there to sniff the side of the log you would have detected the cat-box odor. Female bobcats also scent mark, mostly downward from a squatting position.

Scent marking by wild canids and felids continues through pair formation, den preparation, and birthing. Soon after that hunting begins to regain its importance as the pressure to provide food for the growing young increases. But the timing of reproduction isn’t accidental. The earlier onset of predator reproduction means that their greatest need for food coincides with the greatest abundance of prey animals, which mostly mated in early spring and multiply during spring and summer.

Crossing Paths with the Red Fox

Summer tracking doesn’t often involve those infinitely unfolding trails of winter in which we see extended (to us) segments of the daily lives of animals. Without snow we’re more likely to encounter evidence that reveals the presence of a creature in a particular spot for a mere instant. But I treasure these discoveries just as much, and I find them to be equally valuable as learning opportunities. Imagine you’re out on a pleasant summer hike, and you come to the muddy patch shown in the photo. It’s busy with the tracks of mountain bikes, dogs, and people’s boots, and you’re tempted to simply step around the mess and continue on. But instead you push yourself to look more closely, and you immediately notice a couple of intriguing prints (located just to the right of center in the photo). As you examine them you see that they are the rear (above) and front (below) tracks of a canine, and they surely don’t look like domestic dog. The lower print, shown in the next photo (it’s located down and to the right of center in the first photo), exhibits plenty of revealing detail. The toes are held tightly together, with the outer and inner ones tucked closely behind the two leading toes. There is a nice canine X made by the ridges between the middle pad, the inner and outer toes, and the two leading toes pressed together. The mud is textured by compressed hair, and a chevron-shaped indentation shows in the middle pad. Claw marks are faint except for that of the left leading toe, which is slender and points straight ahead. This is unmistakably the front print of a red fox, and the smaller print ahead and to its left is a rear. Other than those two tracks the fox left little evidence of its passing, but I was delighted to know that it had traveled the same trail I was following.

The hairy feet of the red fox feet set it apart from any of our other wild canines, and the hair sometimes shows beautifully in the fine silt and mud of summer. Here’s a photo from a muddy spot along an ATV trail in which the hair is really obvious. The front track is at the upper right and the rear is at the lower left. (Between them is the track of a raccoon that was turning to the left.) In addition to the hairiness, you can see the difference in size between front and rear tracks as well as the bar in the middle pad of the front print.

These red fox prints turned up along a forest road in a spot that funneled animal movement across a stretch of perfectly moist mud. In the photo you can see a front print in the upper right corner (there’s a maple seed partly covering two toes) and behind that print a rear track, both heading toward the right. In the lower left quadrant are a front and rear that are going in the opposite direction. What I love about these tracks are the peculiar indentations where the surface layer of mud was actually picked up by protruding parts. Take a look at the front track in the upper right corner. The chevron in the middle pad picked up the surface layer of mud and left a slightly curved indentation. The small horny pads that sit at the tips of the toes and protrude from the hair also picked up some mud and left oblong indentations. And the same thing happened in the two leading toes of the rear print (over to the left of the front print) to produce oval indentations. Around some of these holes there are larger shadowy impressions that show where the rest of the toe touched the mud. The hairless protruding parts of red fox feet don’t always show in tracks, and you may wonder, as I have, whether they serve any purpose.

Purely by coincidence we’ve progressed through stages of muddiness from deep and soft through more resistant but still wet to firm with a moist surface layer. So to finish that sequence here’s a print from mud that was almost unyielding and nearly dry. Again it’s a red fox print, but a very different looking one. (The card at the upper left is a one inch square for size reference.) The direction of travel is toward the right, and the deepest marks were made by the claws punching into the mud. The tips of the horny toe pads (the same structures that picked up bits of mud in the previous photo) show behind each claw mark, and in the area of the middle pad we see the chevron. If the fox had been moving slowly we would have strained to detect any evidence of its passing, but this fox was going fast enough for the claws, the small protruding toe pads, and the hairless chevron of the middle pad to push into the hard mud. And here’s a possible answer to our question from the preceding paragraph. These structures must have helped to give the fox traction. Perhaps without them the hairy feet would slip and the fox’s footing would be compromised.