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.

The Precarious Lives of Fawns

Can you see what lies almost hidden in the first photo? At the very center of the frame there’s a bit of bright chestnut color that doesn’t match the faded leaf litter around it. This spot is in a hedgerow that I often pass by when I walk my dog, and that’s what I was doing a few weeks ago when I saw that patch of incongruous brightness. I immediately moved away and headed for home, and my dog never seemed to realize the fawn was there. I returned, sans canine, and carefully approached to take some pictures. The fawn’s spotted coat and bright chestnut color didn’t blend very well with the ground or the green leaves, but its stillness and lack of scent were effective–at least for my dog. When danger is near a fawn’s heart rate and breathing actually slow down, making it even more undetectable.

Very young fawns spend most of their time lying hidden while their mothers forage and rest in separate locations, but this was a surprising place for a doe to leave her fawn. The hedgerow is not far from several village streets and it lies between grass lawns that are mowed regularly. But contrary to what you might think, this closeness to human activity may actually be beneficial. The survival rate for newborn fawns is low–perhaps 50% or less in the first few weeks of life. Any wild hunter that comes close enough to detect a resting fawn will take advantage of the easy meal. For animals like bears, which struggle to find enough nourishing food in early summer, a fawn is a nutritional bonanza. As it lay in the hedgerow, the risk to the fawn from humans and dogs (mostly on leashes) may have been offset by the reluctance of coyotes and other predators to forage in such areas.

Fawns gain strength rapidly, and in a few weeks they begin to move around. The young ones are soon accompanying the does wherever they go, and that’s when we start finding their tracks. Generally the first ones we see are about one inch in length, noticeably smaller than their mothers’ tracks.

But sometimes an even younger fawn leaves visible tracks. In the photo below a housecat print lies on the left, facing to the left, and a fawn track lies on the right, facing right. The cat track was only 1 1/2 inches wide and the fawn print was not quite 3/4 inch long. That’s the smallest fawn print I’ve ever found.

At first does and their fawns move slowly and keep to themselves. As the young ones grow larger they begin to travel more, and family groups may join together in small herds. The photo below shows the tracks of a fawn walking beside its mother.

The hooves of fawns are small copies of the hooves of adult deer, but they don’t show the wear that is characteristic of the hooves of the grownups. In the photo below you see a fawn’s left rear foot. Although this fawn still had a spotted coat, it was old enough that it would have been making limited movements with its mother. But even with its increasing mobility it fell prey to a predator, probably a coyote.

In the next photo you see the tracks of a fawn galloping (or more accurately, bounding) from bottom to top. At first glance the track group may look ordinary, but there’s something unusual about it. The sequence of prints, starting at the bottom, is right front, left rear, left front, right rear. Normally in this kind of movement we would expect the two hind prints to fall outside of the two front prints, but instead the left hind track is just inside that of the left front. It’s as if the left back leg were going to pass to the inside of the left front leg instead of to the outside. You’ve probably seen playing kittens or puppies take on strange positions, and fawns are no different. Their flexible bodies can do things that we don’t often see in adults.

Just as for other animals, play serves a serious function, preparing the fawns for a future that brings all sorts of challenges and dangers. Along with bouts of play, fawns are busy imitating their mothers and absorbing other knowledge: good areas to forage and bed down, escape routes, communication with other deer, and a multitude of other skills that they’ll need as adults. The first three months are the most precarious period of their lives, and once they’ve survived that long, juvenile deer have a much better chance of survival.

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.

What’s Underfoot Makes All the Difference

I’ve been finding lots of coyote tracks lately, and as I go back over my photos I’m amazed at how different they can look from one another. It’s not that the substrates are radically different–just sand, silt, or mud. And to make my point I’ve narrowed down the gaits to just walks and trots. But still, no two tracks are alike. How can what seem like small differences in conditions give tracks such strikingly different appearances?

Moist, dense sand captured the tracks of a trotting coyote shown below, a front at the lower left and a rear at the upper right. The animal’s feet sank in just enough to show lots of details: the difference in size between the front and rear prints, the compact positioning of the toes, the greater depth toward the tips, and the alignment of the claws straight ahead. Both middle pads show only lightly, and the smaller pad of the rear print can barely be seen. In the front track there are small clumps of sand in the two leading toe impressions that were tossed there by the claws when the foot was lifted.

But all sand is not the same. In the photo below of a front print (for the sake of comparison I’ll stick with front prints for the remainder of this article), partial drying resulted in dark toe and middle pad impressions surrounded by lighter dry sand. I suspect that the sand was uniformly wet when the track was made. If the sand around the perimeter of the track had been dry when the coyote’s foot impacted, it would have lost its coherence and crumbled or flowed outwards. Instead pressure from the toes formed plates and fissures (known to trackers as pressure releases). Since nothing disturbed the track before I found it later that morning, these formations dried without disintegrating (although part of the ridge between the two leading toes did fall to the side).

In addition to the larger areas of dry sand there are tiny, light colored squiggles in the floors of the toe and middle pad impressions. These also indicate that the sand was wetter when the track was made; small bits of wet sand adhered to the coyote’s toes and middle pads (dry sand doesn’t do this), and came up as the foot was lifted. Being slightly elevated and also less dense, these particles dried faster than the packed floor of the track. You can see the same thing at an earlier stage of drying in the first image.

This kind of partial drying can often tell us how long ago a track was made. Dew creates wet soil surfaces, so tracks made early in the morning in substrates subjected to dew-fall look uniformly moist immediately after they are made. But on dry summer days the elevated parts begin to lose moisture quickly, and lighter colored halos form around the darker depressed parts of a track. As the substrate continues to dry the entire surface becomes lighter in color and the structure in the cracks and plates disintegrates, resulting in a track with softer edges and uniformly lighter color. Another round of dew-fall and daytime drying may reproduce the halo effect, but the softer edges usually give away the greater age.

The track shown below was made in dry sand, and any structure that existed within the sand disappeared with the impact of the coyote’s foot. Instead of forming plates and cracks in response to the pressure of the foot, the sand moved more like a liquid, producing soft outlines and rounded pressure releases. Although some detail was lost, the compact form of the foot and the triangular shape of the middle pad are still evident. If this track was moistened by dew-fall the night after it was made, it would look wet early the next morning and would develop a lighter colored halo as drying progressed. But the rounded edges would show that it was made at least a day earlier, when the sand was dry.

The photo below shows what fine, moist mud can do to reveal track features. The toes and middle pad are crisply outlined and show very little disturbance, suggesting that it was made at a walk. In front of and behind the middle pad (and a bit at the sides of the toes) there are impressions of the hair which fills the spaces between and around the toes and middle pad–in November, when I found the print, the coat was already thickening ahead of the cold weather to come. We even see the slightly pebbled texture of the skin, especially in the middle pad. This beautifully detailed print illustrates several important diagnostic features of coyote tracks: the trim outline with tightly held, forward pointing toes; the lack of claw imprints telling of shaping through natural abrasion; and the outline of the middle pad with its triangular forward edge and lobed trailing edge.

You may wonder why particles of mud weren’t lifted from the floor of the track the way clumps of sand were in the first two examples. After all, mud is sticky, isn’t it? It certainly is, and the stickiness shows in the narrow ridges pulled in by the toes and the middle pad. This is especially obvious in the lower edge of the left leading toe, the back edge of the right outside toe, and the back edge of the middle pad. But mud is also very fine-grained and has greater internal coherence than sand, so it doesn’t pull apart as easily, especially after it is compressed by the weight of an animal’s foot.

In the next photo the silty mud was not as wet and was much firmer, so the track is shallower and the toes and middle pad look smaller. It’s not that this coyote actually had smaller toes. It’s rather that less of the toe and pad surfaces touched the mud. Think of holding a beach ball and pressing it into soft beach sand to make a large circular impression, then compare that with pressing the ball onto a sidewalk where the contact area is much smaller. The outer toes look especially small, and the lobed trailing part of the middle pad is narrower compared with the same area in the previous photo. Another striking feature is the disturbances in the toe impressions. Cracks and displaced sections in the forward parts of the toes show that the foot pressed backwards against the substrate. These and the tiny punctures made by the leading claws suggest that the animal was moving with more energy (perhaps at an overstep walk or trot) than the coyote that made the track in the previous photo.

Finally, here’s a slightly quirky example of the way tracks can come to have different appearances. I found the print shown below on a truck trail that had been surfaced with pulverized rock quarry tailings. The coyote had walked through a stretch covered with fine white rock dust before it crossed the dried mud in the photo. The dust adhered to its feet and was deposited on the mud to make light tracks on the darker background. As in the previous photo, the toes and middle pad are relatively small and separated by wide negative spaces, but the diagnostic features of a coyote print can still be seen.

There’s so much to learn from tracks: how the track was made, what the conditions were like at the time, how old the track is, and what happened after the animal passed by. We can even get glimpses of some of the challenges in the daily lives of animals. Understanding the subtle (or not so subtle) differences in the appearance of tracks can help us to delve deeper into the myriad messages tracks carry.

Getting to Know Porcupines

I’ve been thinking about porcupines. There are porcupines in central New York where I live, but they’re not common, so in that region (unlike in the Adirondacks) I don’t often encounter their tracks. But this spring we had some late April snowfalls, and on two different occasions I was surprised and excited to find porcupine trails. In the photo below (direction of travel from right to left) you can see the left front and left rear tracks. The hind track (on the left) shows the flattened sole area of the foot nicely, with the marks of the claws to its left. The smaller front print lies to the right but isn’t as clear because the thin snow fractured in the sole area and three of the four claw marks were covered by the hind print.

Those meager April snowfalls weren’t ideal for recording clear tracks, so I’m including a more revealing photo of porcupine tracks that I took a few years ago in the Adirondacks. There was a light skiff of snow on a dark, icy base, and the soles and claws can be seen clearly. Again, the tracks are left front and hind, and the direction of travel is toward the upper left. In the rear print (on the right) the sole is larger but the claws are shorter than in the front print (on the left). If you look carefully at the front track you can see the faint imprints of the front toes (which usually don’t show up at all) just behind the dark holes made by the claws. And those streaks that run toward the upper left from the front claw impressions are drag marks made by the claws as they came forward when the foot was lifted.

So what if there’s no snow? Following trails may not be an option, but porcupines leave plenty of other evidence of their presence. Their winter diet includes the inner bark of trees, both conifers and hardwoods, and the buds and leaves of conifers. Scenes like the one pictured below (on yellow birch) show how efficient a porcupine can be at removing the cambium tissues of living trees. And this kind of evidence lasts long after the actual feeding was done. Small debarked patches high in hardwoods (but not conifers) could also be due to squirrels, which may turn to bark feeding when other food is scarce. However, the amount of exposed wood in the photo below is more than a squirrel would be able to achieve.

To get at tree buds or leaves a porcupine climbs high into a tree (where the most vigorous branches are), bites off twigs, eats the buds or leaves, and then drops the twigs. The photo below shows a scattering of nip twigs which accumulated on the ground as a porky fed in the hemlock tree above. When porcupines feed on the swelling buds of sugar maples in early spring, or on acorns in late summer, they harvest and discard the twigs in a similar manner.

But twigs and branches can fall with no help from porcupines, so how do we know whether a porky was the culprit? The first clue is the relatively even sizes of nip twigs (mostly 1 1/2 to 2 1/2 feet), compared with the wide range of sizes when wind or ice damage is the cause. Another clue is the appearance of the separation site. Randomly broken branches and twigs have ragged, irregular ends. The photo below shows the clean, angled cut found on a red oak twig that was nipped by a porcupine.

To get to feeding spots high in the canopy a porcupine must climb trees, and on trees with light bark, like the aspen in the photo below, climbing marks are very visible. Aspens are sought out by porcupines in spring when the leaves are young and easily digested, and preferred trees are often visited several years in succession. Bears also climb trees to feast on young leaves, nuts, and fruits, but the spacing between porcupine claw marks, between 1/4 and 3/4 of an inch, is much closer than the spacing in climbing marks left by bears.

Porcupine dens are another unmistakable sign. Unlike many other animals, porcupines defecate in their sleeping areas, and when scat piles up they simply plow through it or push it out of the way. The trunk of the sugar maple in the photo below had a hollow space which served as a porcupine den, and the waterfall of scat which fell down from it is evidence of an extended period of occupancy. Porcupine scats are cylindrical to kidney-shaped, and they can also be found among the nip twigs dropped from favored feeding trees.

In spite of their prickly defense, porcupines are preyed upon by most medium-sized carnivores. I found the coyote scat in the next photo last winter, earlier but in the same general area where I found the nip twigs and the tracks in the April snow. The coyote could have been responsible for the porky’s death, but it’s also possible that the initial killer was a fisher, and that the coyote scavenged the carcass later. The quantity of quill fragments is surprising and makes me wonder whether any quills entered the coyote’s body.

By now porcupines have left the mature forests and moved to more mixed habitats where they can find the growing herbaceous shoots and leaves, cattails and other wetland plants, roots, tubers, and fruits that make up their spring and summer diet. There are lots of other animals which consume the same plants, so unless you actually see a porcupine having a meal it’s hard to recognize the signs of summer feeding. But if you’re alert you may find long-lasting evidence of their cold weather activities.

Logs

Living creatures see the world in terms of significant objects. We humans are no exception–for us significant features would be such things as chairs, doorways, computers, streets, buildings, picnic tables, traffic lights….you get the idea. For wild animals rocks, thickets, streams, cliffs, and trees come to mind. And then there are logs–items that we usually ignore unless we’re looking for a place to sit. Downed logs are important to many animals in many different ways, and the evidence is often plain to see.

A chipmunk sat on the log in the photo above to eat a red oak acorn. In order to get at the edible meat, the animal tore narrow strips and small chunks from the outer covering. Logs serve as feeding platforms for many small rodents, including red and gray squirrels, and the leftovers often reveal who the diner was. When squirrels feed on red oak acorns, the shell fragments left behind tend to be larger than those discarded by chipmunks.

The log above was used by a red squirrel feeding on red pine cones. As the squirrel fed it dropped the cone scales and cores on the ground in front of the log to create a large midden. Red pines are self-pruning trees and don’t offer many branch perches, so although red squirrels prefer the safety of branch perches, they sometimes need to use more earth-bound objects. Logs, stumps, and rocks can offer a good view of the surroundings and allow the animal to detect danger.

And how do we know it was a red squirrel? Although gray squirrels do sometimes eat conifer seeds, they don’t store them the way red squirrels do, and they never feed on enough conifer cones to create middens the size of the one in the photo.

Tracks on logs tell us that they can also serve as travel routes. Of course we need snow to see this kind of evidence–the light snowfalls of early winter and early spring often show the prints of animals that walked on logs. The coyote that made the tracks in the photo above found the log to be a convenient route through an area obstructed by branches and undergrowth. Walking on logs may also be quieter since leaves and debris can be noisy, even under a layer of snow. Another advantage of walking on logs is a better view. The greater elevation helps prey animals to detect danger, and predators to detect prey. I’ve found many different tracks on logs–the list includes squirrels, white-footed mice, chipmunks, raccoons, bobcats, bears, red and gray foxes, coyotes, fishers, minks, and weasels.

Logs offer these same advantages when there’s no snow, so we can be sure that animals also walk on logs in warmer weather. Without snow their tracks are difficult to detect, but we may still find evidence of their passing. A long-tailed weasel left the scat shown in the photo above on a mossy log. The scat was not quite 1/4 inch in diameter and contained hairs from a small mammal.

The logs in the photo at the head of this article are ones I visit regularly, and they often accumulate the scat of several different kinds of animals. This suggests that they have some special importance, but I’m not sure exactly why. The log in the foreground bridges a low, rocky gully, but the more distant one lies on more level ground. Both logs are large, but there are other logs nearby that are as big or bigger and don’t accumulate scat. Whatever the reason, we can be sure that each species that travels those logs takes note of the messages left by other creatures.

In addition to serving as perches, travel routes, and bulletin boards, logs may be a source of food. This log was torn open by a black bear in search of the grubs that were living and feeding in the rotting wood. Bears are not the only creatures that find food in logs–skunks, raccoons, and woodpeckers also open logs in search of edible morsels. But the size of the fragments and the distance to which they were thrown could only have be the work of an animal as powerful as a bear.

Have you heard a grouse drumming this spring? At this time of year ruffed grouse are looking for mates. The males seek out large logs, and once they find a log that offers a stable and well elevated surface they send out a kind of drumming sound with their wings. The low sound travels long distances, and the elevation of the log gives it even more range. Females are drawn to the sound, and if they’re impressed they will mate with the male. In the photo above I’m perched on a grouse drumming log, taking a photo with my old SLR camera. In front of me on the log you can see several grouse scats.

Whether they’re dinner tables, highways, message boards, pantries, stages, or even just obstacles, logs are significant objects for inhabitants of the natural environment. The evidence they present can reveal unseen dramas in the lives of animals. So before you sit on that log, take a look at it. You might be rewarded with a message that opens a window into the life of a wild creature.

A Red Wolf Tracking Adventure

A few weeks ago I spent some time at the Alligator River National Wildlife Refuge (ARNWR) on the coast of North Carolina. The refuge covers 238 square miles and includes upland forests, swamp forests, marshes, ponds, creeks, brackish waterways, shrubland, and current and former cropland. The diverse habitats are home to an amazing array of mammals, birds, reptiles and amphibians. I had my first wildlife encounter in a port-a john before I even set foot on a trail. A green tree frog jumped out of the toilet paper dispenser, ricocheted off my arm, and leaped onto the wall. It posed while I got a photo and then scooted straight up the vertical surface.

Green tree frog, ARNWR

With that welcome I knew I was in the right place. But I was really there because of one specific animal–the red wolf. Alligator River is home to the only wild population of red wolves in the world. Historically the range of the red wolf stretched from Texas to the Atlantic seaboard, and from the Gulf Coast to the Ohio River valley. But persecution and habitat loss decimated populations throughout the range, and by the mid-1960s just a few small remnants remained in the coastal prairies and marshes of western Louisiana and eastern Texas. Red wolves were on the verge of extinction, and the U. S. Fish and Wildlife Service determined that the best strategy was to capture the last wild wolves and move them to captive breeding facilities. The red wolf pictured below was photographed at a facility in Texas. After several decades of captive breeding, 4 male-female pairs were released at ARNWR. The animals have thrived there, and the red wolf recovery program is seen as a model for reintroductions of other species. You can learn more about the program here.

Photo by the U. S. Fish and Wildlife Service

The more I thought about this amazing story, the more I wanted to go there and see red wolf tracks. So about a month ago I set off for North Carolina. I had high hopes, but I didn’t know how hard it would be to find the wolves or what kind of tracking conditions I would encounter.

I learned more about the current status of red wolves and strategies for their future when I visited the Red Wolf Education and Health Care Facility in Columbia, NC. There’s lots of information on Center’s website, which you can find here. If you ever visit ARNWR you should definitely stop at the Red Wolf Education Center.

Red wolf front track, ARNWR

One helpful bit of information was that the red wolves spend most of their time in the northern parts of the refuge around the agricultural areas. And once I did some exploration and located the sandy roads and trails, I found wolf tracks aplenty. Red wolf tracks are similar to other wild canines–they have the typical central dome and canine X, and the claws usually show as small indentations ahead of the toes. The species most likely to be confused with the red wolf is the coyote, but there are several features that set the two animals apart. Compared to coyote tracks, red wolf tracks are wider in proportion to their length, and have larger middle pads.

Coyote front track, Lewis County, NY

There’s also a distinct difference in size. Red wolf front tracks range from 2 1/8 to 3 inches wide and 3 to 4 1/4 inches long. Even our northeastern coyotes–larger than western coyotes–fall in the lower end of this range. The coyotes at ARNWR are more like western coyotes in size, so their track dimensions don’t overlap those of red wolves. I didn’t find any coyote prints in the areas where the wolf tracks were–apparently the wolves don’t tolerate the presence of coyotes. The coyote front print below, which I found in the southern part of ARNWR, measured 2 5/8 inches in length and 1 3/4 inches in width.

Coyote front track, ARNWR

Here’s another photo of red wolf tracks, and these are also distinctly different from coyote tracks. The overall shapes of both the front track (upper left) and the hind track (lower right) are more rounded, and the middle pads are larger and more triangular. As in other wild canines, the front tracks of red wolves are larger than the rear tracks, and the claws don’t always show on all the toes.

Red wolf front and rear tracks, ARNWR

ARNWR is a haven for all sorts of wildlife, and one group that was clearly thriving was snakes. Several times I saw snakes basking on roads, and every time the snake was very reactive to my presence, either fleeing or adopting a defensive posture. On my way out one afternoon I came upon this very large–at least four feet long–rattlesnake. (I wasn’t as close as it looks–I used the telephoto setting to get this photo). But there was something wrong with this snake. It wasn’t moving away or coiling up, and it seemed unable to raise its head or straighten out its neck. There was no obvious wound, but it must have been hit by something.

Rattlesnake, ARNWR

The next morning I drove in on the same road, and where I had seen the snake the day before I saw this:

Remains of rattlesnake eaten by red wolf, ARNWR

Along the sandy edge of the road I found wolf tracks leading up to the snake carcass and then continuing in the same direction away from it. To make a meal of the disabled snake, the wolf must have known not only that the snake was vulnerable, but also how to go at it without getting bitten. For me this was an incredible look at a slice of the life of a red wolf, and at the way the animals make use of every opportunity. Their intelligence and adaptability has served them well for thousands of years. If we just give them a chance they can thrive for thousands of years into the future.

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.