snow tracking – Linda J. Spielman

When Animals Break the Rules

Bobcats walk in direct register. Deer walk in indirect register. Red foxes have a bar in the middle pad of the front foot but not in the rear foot. Fishers move at a lope or bound. Cats have four toes. These and other statements are the received wisdom of the tracking literature. But are they always true? As we’ll see in the following paragraphs, there are exceptions to even these seeming inviolable maxims.

Let’s start with walking deer. They do indeed place their feet in indirect register most of the time. The photo below shows tracks made by a deer walking in indirect register toward the upper right. At the lower left you see a left rear print partly superimposed on the left front print. Roughly in the center of the photo there’s a right front track with a right rear track partly on top but a little behind. At the upper right the left rear track sits a little behind and slightly to the inside of the left front track. The zig-zag pattern is the signature of the walk, and each set of impressions is made up of the front and rear prints from the same side. It’s the partial superimposition of the two prints that makes it an indirect register walk.

Direct registration occurs when the rear print is perfectly superimposed on the front print. As the next photo (the trail of a white-tail deer walking from right to left) shows, this does occur, especially in younger deer.

As this close-up (from a different trail from the one shown above) shows, direct registration makes it hard to tell if the track was made by two feet or just one. Among all the deer trails you see, there are bound to be a few that show direct registration.

Bobcats are said to walk in direct register, but again this is not an absolute. The bobcat trail in the photo below (direction of travel from left to right) is in very obvious indirect register. The zig-zag pattern indicates the walk (and as a side note, you can see how much narrower it is than the zig-zag of the walking deer). In each set of two prints the hind print falls partially but not perfectly on the front print.

In case you have some doubts, a close-up from a different part of the same trail will convince you that this is indeed a bobcat trail.

Was the bobcat distracted? Or tired? We’ll never know. Later in the same trail the animal switched to an overstep walk, a gait that’s often seen in bobcats, so its overall behavior didn’t throw up any red flags.

The next photo shows a direct register trail made by a bobcat walking toward the upper left. In each impression you see what appears to be a single track, but is actually two tracks, the rear print superimposed on the front print. And here’s another interesting aside: The concave hollows around the tracks are not connected to registration, but were instead made by the thick fur covering and surrounding the bobcat’s feet. They’re known as hair halos.

Staying with felines for the moment let’s look at toes, which are supposed to be four in number (counting those which normally touch down) in both wild felines and domestic cats. In the next photo you see some tracks which are clearly feline, but don’t fit the four-toed paradigm. My friend Ben Altman has two house cats, both of which have feet with more than the standard four toes. This is called polydactyly and it’s caused by genetic mutations. It’s not uncommon in domestic cats but is rare in wild felines.

We’re told that fishers prefer to move at a lope or a bound but this, too, is not always the case. In the next photo you see a fisher trail going from lower left to upper right and a red fox trail moving from bottom to top. The fox is travelling at a lope, a gait similar to the habitual gait of a fisher. But what’s the fisher doing? Definitely not the typical lope or bound. Because the front tracks of the fisher are larger than the hind tracks we can work out what the gait is. At the very lower left in the fisher trail there’s a right rear print, and the sequence of the next eight tracks (up until the pattern changes at the upper right), is: right front, left front, right rear, left rear, right front, left front, right rear, left rear. This extended pattern shows that the fisher was speeding along at a flat-out gallop. Fishers don’t often do this, but they obviously can. Something alarming must have pushed the animal into unusual speed.

One of the absolute statements we often hear has to do with red fox tracks. The going wisdom is that there’s a bar or crescent shaped depression in the middle pad of the front track, but not in the rear track. A ridge of horny skin that protrudes through the hairy covering of the pad is the source of the bar, and it’s supposed to be absent from the middle pad of the hind foot. Here’s what we’re accustomed to observing–notice the bar in the front middle pad (on the left) and the absence of the bar in the rear middle pad (on the right).

But on rare occasions we see red fox tracks with a bar in the middle pad of both the front and rear prints. Here’s one example. The front track is at the lower right and the rear track is at the upper left.

Just so you don’t think this is a one-off, here’s another example. The front print is in the upper right and the rear print, with a reduced but visible bar, is at the lower left. (The carboard square in the upper left is one inch on a side.)

Raccoon trails are a common find, and the next photo shows the way a raccoon pace-walking trail is supposed to look. What we expect to see is sets of two prints, each set a front from one side and a rear from the other side. In the photo the direction of travel is from lower left to upper right, and the hind prints are larger than the front prints. Starting at the lower left, the first set is left front with right rear, the second is right front with left rear, the third is left front with right rear, and the last is right front with left rear.

The raccoon which made the trail in the next photo (direction of travel lower left to upper right) appears to be in serious violation of the rules of tracking. Instead of alternating front and rear tracks there are two sets with left rear and right front, then two sets with left front and right rear, and again two sets with left rear and right front. Can a raccoon even do that?

The answer is, no, a raccoon can’t do that. But two raccoons, one following close behind the other, can do that. It you focus on every other set of two you’ll see a normal raccoon pace-walk trail. So what appeared to be an impossible situation turns out to be a perfectly normal, albeit unusual, event.

We need to learn what’s most common in animal tracks and trails, but we also need to think out of the box when faced with uncommon track and trail patterns. Whether it’s two animals conspiring to create a confusing trail, or one animal with an unusual track or behavior, nature can always throw up something we’ve never seen before. It may take days, weeks, or even months to understand what we saw, but that’s part of the excitement of tracking. It’s why we keep coming back for more.

Bringing Home Dinner

When we come upon a site where a predator killed a prey animal, we’re able to see in detail the interaction between hunter and hunted. But finding such a site is a rare. It’s more common to find the trail of a successful hunter carrying its prey, and this also makes for fascinating study. To understand such a trail we must pick out the crucial evidence from the other disturbances that occur in animal trails. Let’s start with a fairly straightforward example.

In the photo below you see a trail made by a fisher loping from left to right. There are three typical fisher track groups, each group a place where the fisher landed and then took off. Above each track group you can see a curving gouge in the snow made by something the fisher was carrying. But what exactly was being carried? Could it have been a stick? Not likely, based on the length of the trail involved (it went on for quite a distance) and the consistency of the patterns. There’s also the fact that the marks are curved, suggesting that the item being carried was swinging slightly. (If you visit a place where dogs have been playing with sticks you’ll see how different it looks when a stick is being carried.) The predator would have been gripping the body of its prize, and something that extended to the side would have touched the snow at each landing. The curving marks are actually made up of two parallel lines, and these lines seem too widely separated to be claw marks from a dangling foot. Their size and positioning do seem about right for the tips of wing feathers, suggesting it was a bird. If it was a bird it couldn’t have been large, since it only touched the snow at the low points in the fisher’s bounding gait. A turkey would be much too big, and even a grouse would probably have left more traces in the snow. Perhaps it was something the size of a blue jay or a junco.

A short-tailed weasel bounding from upper left to lower right made the trail in the next photo. The trail consists of paired track impressions, a common pattern for small mustelids. To the left of each set of weasel prints there’s a thin, slightly curved line in the snow. There’s also a shorter and wider mark just ahead of the weasel tracks. The thin lines are the right size for a tail, and the wider depressions could have been a foot. Given the small size of a short-tailed weasel, it’s likely that the predator was carrying something equally small. A white-footed mouse seems unlikely, because its long tail would have made a longer stroke in the snow. My guess is either a meadow vole or a woodland vole.

The next photo shows the tracks of a fisher loping from right to left, and just below the tracks you see a wide groove. Below that groove you can see several lighter lines. These finer marks aren’t completely parallel with the deeper groove, so the deep groove and the fine lines must have come from separate body parts. The wider groove seems too deep and even to be something as light as a feather–was it a tail or perhaps a thickly furred foot? The finer lines could be the marks of dragging claws. This example is less clear than the two preceding ones, but I’m inclined to think the prey item was a mammal, perhaps a rabbit.

Now to some examples of marks that we often find in animal trails that don’t indicate dragging parts of a prey animal. In the next photo you see the trail of a long-tailed weasel bounding from bottom to top. There are grooves behind each landing spot, but they weren’t made by something being carried; the marks were made by the animal’s tail. Each time the weasel took off for the next bound its body sank into the snow, and the tail left a tapered groove. Tail marks are always connected to body impressions rather than being off to the side of the tracks as they are in the three preceding photos.

Here’s another example of potentially confusing disturbances that are not indicative of something being carried. The next photo shows the trail of a fisher walking from the lower right to the upper left. The fisher dragged the tips of its feet through the snow with each step. Notice that the drag marks are within the trail rather than to the side, and each drag mark extends completely or partially between two tracks.

Drag marks aren’t always as obvious as the ones shown above. In the next photo you see the trail of a coyote walking from top to bottom. In the lowest part of the photo there’s a thin line that was made by a single claw. There are wider gouges above that made by the rounded tips of the feet. But again the grooves lie within the trail width and always connect to tracks.

In the next photo we see what at first glance looks like the trail of some kind of otherworldly creature. It’s actually several coyote trails moving from left to right on a frozen waterway. To sort this out we need to focus in on the trail of each individual animal. The central part of the sequence draws our eye first: There’s an wavy drag mark that seems connected with the series of tracks in the center. If we look at just those tracks we see that they were made by a walking coyote. The drag mark seems to touch the prints, but toward the right it swings to the side and misses the tracks. This tells us that it’s not a foot drag but something that’s being carried. Above the central area there’s a similar string of tracks, and if we concentrate on those we see that they were made by another walking coyote. A third track sequence which lies below was made by yet another walking coyote. The outer trails are close to, but not on top of, the central trail, so there must have been two animals following close behind the one with the food item.

This scenario is supported by the next photo, which was taken in a place where the coyotes slowed down to go through a culvert. The tracks are closer together and the drag mark is more irregular. The drag mark touches one coyote print but misses the others, so it wasn’t made by the coyote’s feet. It’s definitely evidence of something being carried.

As to what was being carried, we can say it was a medium-sized object with a blunt projecting part and enough weight to make a deep groove in the snow. Claws would be thinner, an animal’s nose would be wider, an ear would be softer, and a tail would be fluffier and lighter. That would seem to eliminate all the medium-sized, winter-active animals in our region. But there’s another possibility: the detached body part of a deer with a protruding bone. The area where I found these tracks is a popular spot for hunters, and in mid-December, when I took the photos, coyotes would still have been scavenging on deer carcasses.

I’ll never know for sure, but a deer part is a reasonable conjecture, and conjecture is often what we’re left with when we attempt to understand the trail of a predators carrying dinner. Even without definite conclusions, the process of sorting out the details can be satisfying in itself.

A Family Resemblance

Rodents are the most common mammals on earth, in both number of individuals and number of species. They are also the most diverse, with lifestyles that range from semiaquatic through fossorial (adapted for digging and living mostly underground), terrestrial, arboreal, and even semi-aerial (gliding flight). But don’t let that mind-boggling profusion intimidate you. In our region many of the most common rodents are members of the squirrel family, a group that is remarkably uniform in physical features. Fortunately for the tracker this uniformity extends to track details and track patterns, and familiarity with the key features will aid in the recognition of any member of the group.

In the photo below you see tracks made by a gray squirrel bounding toward the top of the photo. The five-toed rear tracks lie in the upper part of the image, and the four-toed front tracks can be seen in the lower part. Claw marks show as tiny pricks ahead of the toes of both front and rear tracks. Notice that the toe pads of the three middle toes of each hind print are lined up close together, while the inner and outer toes lie farther back and angle to the sides. Behind the toes you can see a C-shaped grouping of middle pads. The front tracks have only four toes, but again the central two point more forward while the outer and inner ones point to the sides. C-shaped arrays of middle pads sit behind the toes of the front prints, and heel pads (there are two on each foot, but it’s hard to tell in this image) are situated behind the middle pads.

Bounding is the most common gait for most members of the squirrel family, and the resulting pattern is another recognizable trait of the group. In the photo above the two rear prints are almost even with each other and are set wider and well ahead of the front ones, which are also nearly even with each other. This positioning may seem odd, but there’s a logical explanation. At each bound the animal lands on its front feet and draws its rear feet forward so they pass outside of its front legs. As the front feet lift off the rear feet touch down–ahead of the spots the front feet just left–and propel the next leap.

The next photo shows a bounding pattern made by a red squirrel, again travelling from bottom to top. There’s a striking similarity to the first image of the gray squirrel tracks, in both overall arrangement and track details. Because the substrate was softer the rear feet of the red squirrel (in the upper part of the frame) sank in deeper–notice that the whole length of each of the three middle toes registered as a narrow groove. Nevertheless the three toes are closer together and oriented more forward than the outer toes, just as they were in the gray squirrel tracks. In the front tracks of the red squirrel (in the lower part of the photo below) the claws show as grooves rather than pricks, but the overall structure is similar to the front tracks in the preceding shot. If you look at the red squirrel’s right front print (at the lower right in the photo below) you can see clear impressions of the two heel pads.

The chipmunk tracks in the next photo (again bounding toward the top) are consistent with the features we saw in the red and gray squirrel prints. In the right rear print (in the upper right quadrant) you can see that the middle toes are closely grouped and the inner and outer toes are angled to the sides. The left front track (in the lower section a little below and to the left of the right front track) shows the four clawed toes, the C-shaped grouping of middle pads, and the two heel pads.

Mud is great, but winter is also fine for seeing squirrel family connections. In the photo below of red squirrel tracks in snow (bounding toward the top, of course) you see the same characteristic features you saw in the mud tracks. As sometimes happens, the heel area of the right rear foot (at the upper right of the photo) registered as a flattened area behind the middle pads. (If you look back at the first photo of the gray squirrel prints you’ll notice that the heel area of the left rear foot also made a slight impression.) There’s a variation in the arrangement of the front tracks, with the right front well behind but the left front farther forward. This kind of foot placement is often seen in squirrels, but is less common than the more four-square pattern.

Flying squirrels possess gliding membranes (the patagium) which extend between the front and rear legs, and because of this the rear feet can’t pass as far ahead of the front feet as they do in red or gray squirrels. In the next photo you see a bounding pattern made by a southern flying squirrel (oriented toward the top) in which the front prints are situated between rather than behind the rear prints. In northern flying squirrel trails the front prints often lie ahead of the rear ones. Another special flying squirrel trait is the thick covering of fur on the undersides of the feet. Because of this flying squirrel prints rarely show the crisp detail found in the tracks of other members of the squirrel family. But even with these differences, flying squirrel tracks will remind you of the tracks of other squirrels.

In the next image you see a bounding pattern made by a woodchuck. If you didn’t realize that woodchucks belong to the squirrel family, the familiar features of their tracks should make that clear. Woodchucks are more likely to walk than bound, and when a woodchuck does bound it usually places its front feet in a staggered pattern rather than even with each other, as in the photo. Nevertheless, the overall arrangement and the track details are consistent with those of its relatives.

To complete the picture for small rodents in the Northeast we need to add a few creatures that don’t strictly belong in the squirrel family but leave distinctly squirrel-like prints. These include white-footed mice, meadow voles, and their allies. I include mouse and vole allies because each one represents a group of closely related species which are difficult to distinguish from tracks alone.

First, let’s look at tracks of the white-footed mouse, shown below in a bounding pattern heading toward the upper right. In spite of its smaller size, the animal made tracks that are uncannily similar to the tracks in the first three photos. If I didn’t tell you that an individual rear print is just half an inch across you’d be hard pressed to tell these tracks from squirrel tracks.

Vole tracks also show striking similarities to the tracks we’ve already discussed–but with a few important differences. In the next photo you see tracks made by a meadow vole bounding from bottom to top. The track sequence, starting at the bottom, is: right rear, right front, left rear, left front. This staggered arrangement is common in vole trails and differs from the more consistent four-square bounding patterns usually seen in white-footed mice and tree squirrels. Voles can leave more regular bounding patterns, but they often move at something between a bound and a lope and their track patterns tend to be more variable. The toe impressions in vole tracks also tend to be more finger-like than the toes of mice. In spite of these differences the tracks of voles will remind you of mouse and squirrel tracks.

This is all well and good, you may say, but if these creatures are so similar to each other, how can I tell them apart? I’ve mentioned a few variations that can be helpful, but often the most useful trait is size. There’s a neat size progression, and although there’s some overlap between adjacent species it’s usually possible to make an identification with a few measurements combined with other clues. There are two dimensions to consider: track width (more reliable than track length) and bounding trail width (measured perpendicular to the direction of travel across the widest part of a bounding pattern). I’ll focus on the big picture rather than giving an exhaustive account of the numbers–detailed measurements can be found in any good tracking guide. White-footed mice and the smaller voles (woodland voles, for example) are the tiniest of the lot, and meadow voles are slightly larger. Chipmunks come next, and southern flying squirrels are slightly larger than chipmunks. Northern flying squirrels outweigh their southern kin, and red squirrels are larger yet. Gray squirrels beat out red squirrels, and woodchucks complete the series. These differences in body size are reflected in differences in track and trail dimensions, so a few measurements are usually sufficient to clinch an ID. Even when the tracks you’re dealing with are in the overlap zone there are usually other clues that can point toward an identification. And when all else fails, it’s okay to say you just can’t be certain. If you treat each situation as a learning experience, you’ll find yourself stumped less and less often.

Gray Fox Affairs

It’s been a strange winter. In my neck of the woods we had some significant snow early in the season, but no big storms since then. Temperatures have been up and down (more up than down), and with all the melting, the snow we do have has consolidated into a dense, icy layer. Much of the time the conditions have been terrible for tracking, but every once in a while something wonderful has happened: warmth and liquid precipitation have been followed by dropping temperatures and a change from rain to snow. When this happens, snow that falls while the air is still relatively warm becomes bonded to the crust. As the temperature drops and additional snow falls, it forms a soft layer on top. The result is a non-slip and easily navigable surface that is a perfect medium for recording tracks.

A few days ago I encountered just such conditions: an icy base covered by a thin layer of soft snow. I was in an extensive natural area, and both the forest road I was following and the surrounding landscape offered beautiful tracking conditions. Animals of all sorts had been moving easily over the snow, and there were tracks everywhere. I found myself following the trail of a gray fox. The animal went for quite a distance at an easy trot, but then it did something that was quite puzzling.

The photo below shows the fox trail as it goes from upper left to lower right. (You can also see a coyote trail to the right of the fox trail, and a mountain bike trail to the right of that.) As it entered the frame the fox was walking (the first three tracks at the upper left). In the next section (between the last walking step and the edge of the tree shadow) the pattern was very different, and following that the trail looks unlike either of the previous sections. I wanted to know what was going on and why the middle section looked so different.

In a situation like this the first thing to do is identify each track. The zig-zag of the walking section helps us to tell right and left, and the fact that the front foot is larger than the hind foot distinguishes front from rear. The next photo shows a gray fox front print on the left and a gray fox rear print on the right. You can see the difference in overall size and also the difference in the sizes of the middle pads.

The photo below shows just the puzzling middle section, and if you compare photos you’ll see that the front and rear in the photo above are actually the first two tracks in the middle section. It’s pretty clear that the first four prints in the photo below are left front, left rear, right front, right rear. After that it gets harder. The track just above the right rear is smaller than the one to its right, so those two prints must be left hind, left front. Three tracks from the right side come next, and it looks to me like the sequence is right rear, right front, right rear. The final two before the tree shadow are the left front and the left rear, and at the edge of the tree shadow there’s a right front with a right rear partially superimposed on it.

In the next photo I’ve added labels showing my take on right/left and front/rear. If we start at the beginning of the whole sequence, the animal was trotting (those tracks aren’t seen in the photos) and then slowed down to a walk (the first three tracks in the distance shot). The next section shows that the fox slowed even more to an overstep walk (the first four prints in the photo below), then slowed even more to an understep walk. There’s an extra right hind that’s puzzling, but I’m guessing the fox just repositioned its right hind foot. Then the overstep walk reappears after which the fox picked up the trot (the two impressions at the lower right in the first photo). Notice that the step lengths in the overstep part are shorter than the regular walk steps that preceeded them, and the step lengths in the understep part are shorter yet.

That analysis was rather involved, but it leads to a picture of what the fox actually did. As it trotted along something it detected made it slow down, first to a walk and then almost but not quite to a standstill. It was probably sniffing and listening intently as it moved very slowly. Once the animal concluded that it was okay to move on, it resumed its journey at a trot. It’s impossible, without more evidence, to know what caused the fox to react the way it did. It may have been a threat, but it could also have been something that interested it for a different reason. It is, after all, mating season for wild canines.

And the fox I was following was definitely tuned in to mating season. Farther on I found a spot (shown in the next photo) where the animal had detoured to urinate on a small spruce branch. If you look in the center of the frame you’ll see a squiggle of urine that runs horizontally from the upper edge of the spruce branch. Because the urine wasn’t squirted out the side of the tracks we know this was a female. She would have lifter one hind leg forward and supported herself on the other hind leg (plus two front legs) as she urinated. The relative depths of the tracks tell us that the supporting rear foot was the left. Its track is in the prominent double impression above and to the left of the urine.

I’ll never know what made the gray fox slow down and leave the pattern discussed in the beginning of this article. It could have been a threat–there was certainly a coyote in the neighborhood, or it could have been the mountain biker. A fisher (whose tracks I also found on that day) would have made the gray fox nervous. And there were red fox trails as well. But the trail shown in the photos above doesn’t suggest alarm so much as cautious interest. The fox didn’t change direction but just continued on. Was it another gray fox, one she was familiar with, or one she had mated with in a previous year? We have a small part of the whole story, and we can only speculate about the rest, but it’s fascinating just as it is.

Mouse Maneuvers

The mouse–not most people’s favorite creature, to put it mildly. Certainly the house mouse can be a serious pest, but wild mice are different creatures altogether. To start with, they are more attractive than the drab house mouse, as you can see from the portrait of a white-footed mouse which heads this post. The white-footed mouse is one of two species which inhabit the northeast, the other being the deer mouse. They are closely related (both belong in the genus Peromyscus) and are so similar they can’t be distinguished from tracks or sign. Habitat may indicate which one we’re dealing with, but from the tracker’s perspective it’s not really important, since they have similar characteristics and behaviors. White-footed mice prefer deciduous and mixed forests at low and moderate elevations. The trails shown below were most likely made by deer mice, which are more common in boreal and high elevation forests.

Both deer and white-footed mice are hunted by just about every predator in our region, so they stay hidden whenever they can. In warm months they find safety within woody debris, shrubs, blowdowns, rocks, log piles, and sometimes human structures. In winter, snow usually provides ample cover. Mice are able to tunnel through snow if it’s not too dense, and deep snow actually contributes to their survival. Within a deep snowpack the temperature is highest at ground level and decreases toward the surface. The temperature gradient causes ice crystals in the lower levels to sublimate and recrystallize at higher levels, leaving spaces where small animals can find safety and warmth. Hollows at tree bases, among rock outcrops, and under downed logs and branches allow mice to move between the surface and the lower regions (the subnivean zone). That’s why the trails in the photo above radiate from the base of the tree at the upper edge of the photo.

The next photo shows a steep, snow-covered embankment at the edge of a groomed snowmobile trail. A mouse (it could have been either a white-footed or a deer mouse) bounded from the lower left across the packed snowmobile trail toward the slope. The mouse turned to the right and then went under a slight overhang where it found (or dug) a tunnel leading to safety in the deeper snow bordering the snowmobile trail.

Look under the log in the next photo and you’ll see mouse trails. Notice how the mouse trails run into (or out of–or both) the cavity at the upper left, a mouse-sized hole at the lower right, and unseen openings under the lower part of the log. As long as these openings are maintained, mice can move easily between the snow surface and the subnivean realm. The log also provides protection from aerial predators.

In soft snow mouse trails on the surface often lead to holes that connect to tunnels deeper in the snow.

Both deer and white-footed mice store nuts and seeds in cavities in logs, standing trees, and rock piles. Once winter comes any space protected by deep snow makes a good feeding area. The midden of black cherry seeds in the next photo shows where a mouse fed beneath the snowpack at the base of a tree. The neat round holes are reliable indicators of mouse feeding.

Mice use logs as travel routes, but we only see evidence of this when a light covering of snow coats the log surfaces. In the photo below you see a jumble of mouse tracks, a few of which show toes clearly enough to reveal the direction of travel. There’s a rear print at the lower left that points toward the left, and you can see a few front tracks near the upper edge of the snow with toes pointing toward the right.

There are other small mammals, voles and shrews in particular, whose trails can be confusingly similar to those of deer and white-footed mice, especially when they are bounding. But the bounds of voles and shrews are less regular and have more variable foot placement than the bounds of mice. Voles and shrews also use a greater variety of gaits than mice, including walks, trots, bounds, and lopes. Voles especially are likely to make frequent gait transitions, and often use a perplexing gait sometimes described as a shuffle. Mice can walk but it’s rare, and I’ve never seen evidence of a mouse trotting, shuffling, or loping.

Deer and white-footed mice are relatively long-legged and athletic, and they sometimes make long leaps. Voles and shrews, with their chunkier bodies and shorter legs, can’t jump nearly as far. So if you find a trail with leaps like those in the photo below, you can confidently assign it to a mouse rather than a vole or shrew. The tail marks are another clue. Mice have tails as long or longer than their body length. Both the short-tailed shrew and the woodland vole, the two species most likely to be confused with deer and white-footed mice, have very short tails and wouldn’t leave long tail marks like the ones in the photo.

The white-footed mouse trails in the next photo show the typical consistency of pattern and leap length, but the one on the left demands a second look. It begins at the bottom, a little to the right of center, goes upward for a few leaps, and then takes a hard turn to the left. After a few more leaps the trail circles back to the right and proceeds toward the top of the photo where there’s a fallen branch sticking out of the snow (just outside the frame). Each time it turned the bounding mouse flung its tail to the outside for balance, leaving conspicuous tail marks. There’s a pile of snow that was kicked toward the rear where the mouse turned left, and where the trail curves back toward the right the landing/takeoff depressions are deeper. These observations suggest extreme bursts of energy.

We’ll never know for sure, but the most likely explanation is that a threat spooked the mouse. There’s no sign of an actual attack, so the mouse evidently survived, but it must have been alarmed by something. Deer and white-footed mice, along with other small rodents, are in constant danger of predation, and we sometimes find evidence of a successful hunt (see my post for March 1, 2022). But most of the time mouse trails tell us they survived to live another day.

Possum Puzzles

The opossum is a humble animal, slow moving, shy, and generally of a placid disposition. But opossums can present surprising challenges to the tracker, not the least of which is getting a handle on the tracks themselves. To understand opossum tracks it may be helpful to see the animal’s actual feet, so let’s take a look. The photo below shows the underside of the left rear foot of an opossum–it resembles a human hand with a large, widely angled thumb and four additional, finger-like toes. If you hold up your left hand with the palm facing you, you’ll see the resemblance. Try to imagine your hands as the rear feet of the animal.

In the next photo you see the opossum’s left front foot–very different from the rear. The five toes of the front foot are somewhat finger-like and similar to each other in shape, and the middle pads are quite bulbous. Both front and rear feet are adapted for climbing but are less ideal–especially the rear feet–for moving on the ground. This, combined with the animal’s heavy body and relatively short legs, means opossums are not very agile.

Now let’s look at opossum tracks. In the photo below the right front track lies on the left and the right rear track lies behind it on the right, both tracks oriented toward the left. The spreading toe indentations of the front track radiate from a compact grouping of middle pad impressions. In the rear track the thumb points to the side (downward in the photo), and the other four toes are closer together and angled to the opposite side (upward in the photo).

Because the opossum rarely moves faster than a walk (or sometimes a trot), front and rear prints are often partly superimposed, and that’s another source of confusion. (The animal whose tracks are pictured above was drinking at a puddle, so it left some nicely separated prints.) In the photo below you see a left rear and a left front track, oriented toward the right. The two tracks are so close together it’s hard to tell where one ends and the other begins. If you look at the right side of the frame you’ll see five similar toe marks radiating outward from four closely set middle pad impressions. That’s the left front track. The hollow made by the thumb of the left rear track sits just behind the front middle pads, and above it you can see the middle pad and toe indentations of the left rear track.

The indirect register walk is the opossum’s preferred gait, so we often see sequences of front and hind prints like the ones shown above. In the photo below an opossum walked from the lower left to the upper right, leaving the zig-zag pattern typical of the walk. Each angle of the zig-zag is composed of front and rear prints from one side, and in each of these couplets the hind print lies just behind the front print. The sequence of tracks is right rear, right front, left rear, left front, right rear, right front, left rear, left front.

When tracks are less distinct, possum trails can be downright perplexing. The next photo shows another walking opossum trail, again proceeding from lower left to upper right. The rear feet fell farther behind the front feet at each step, but the zig-zag pattern can still be seen. A few of the prints are recognizable as possum tracks, and the rest are just weird looking.

If an opossum needs to move a little faster it shifts into a trot, leaving a trail like the one shown in the next photo (oriented from lower left to upper right). It’s harder to sort out front and rear tracks in this trail because the snow was dry and the faster gait created more disturbance. But if you look closely you’ll see that the rear tracks are consistently just behind the front tracks. The sequence of prints is right rear, right front, left rear, left front, right rear, right front, left rear, left front.

We know it’s a trot because the trail is straighter than the walking trails shown in the previous photos, and the distances between the sets of tracks are slightly greater. There must have been a slight hitch in the gait of the animal that made this trail, because the claws of one of the right feet (it’s hard to tell whether it was the front or the hind) seemed to brush the snow each time it moved forward to the next landing spot.

You may have noticed that none of the possum trails I’ve shown so far have tail drag marks. Opossums don’t drag their tails as often as people may think, but it does sometimes occur. Here’s a photo of a possum trail (oriented from upper left to lower right) with a nice tail drag mark. Don’t worry if the direction of travel isn’t obvious–it’s hard to tell from the photo because of the angle. A fox left a galloping trail on the left side of the frame, moving from bottom to top.

Much of the opossum’s winter diet comes from scavenging on carcasses, and the animals don’t generally move very far away while a food source lasts. So if you come across a possum trail it’s worth following–you may find a feeding site, or even a den like the one shown in the next photo. I had to climb through and around lots of tangles and thickets, but I eventually found the den the opossum was using while it fed on a deer carcass not far away.

Opossum tracks and signs give us a window into the lives of the animals. But I’m fond of them for an additional reason: the tracks are just so quirky. In fact, the consistent peculiarity of possum tracks is one of the clues to their identity. So be alert for weirdness, and when you find it, consider the opossum.

Seeing the Forest And the Trees: Lessons from Raccoons

Details versus the big picture–in tracking we need both, but sometimes one can get in the way of the other. We can focus too closely on the small details and miss the overall view, or we can see a larger pattern but miss the crucial fine points. The tracks of the raccoon present challenges on both levels, so they can be helpful for balancing both perspectives.

In the photo below you see two raccoon tracks, a left rear (on the left) and a right front (on the right), oriented toward the top of the frame. Both tracks have the five finger-like toes characteristic of the raccoon. Indentations made by the claws can be seen ahead of each toe, and the undivided middle pads show behind the claws. There are also heel impressions in both front and hind tracks. They’re not as deep as the impressions of the toes and middle pads, but they show up because their texture matches the texture of the other parts of the tracks.

Compare the left rear track shown above to the left rear print in the next photo. In the image below the toes are also finger-like, and they’re held even more tightly together, but the middle pad looks different–it’s shaped like a trapezoid rather than a C. There’s also no heel impression.

The next photo shows a right front print. It’s toes are similar to the toes of the right front in the first photo, but they spread less. And the middle pad is not quite the same; instead of being symmetrical it extends farther back on the outside of the foot. Another difference is the lack of a heel impression.

In general front tracks are smaller than rear tracks and have more spread in the toes. The middle pads of front and rear prints also differ: those of the rear tracks are generally broader with more gently curved front edges than those of the front tracks. Because of these differences it’s usually possible to tell front from rear prints in the raccoon.

It gets trickier when the tracks are incomplete. In the photo below of a right front raccoon track (oriented toward the left) only four toes show, and they’re not very finger-like. The middle pad impression is faint, and you need to look closely to see the curved leading edge. This kind of track could easily be mistaken for that of a different animal.

But we don’t want to miss the forest for the trees. The arrangement of a series of tracks is as important as the details in the individual tracks. The image below shows the typical pattern of a raccoon moving at a pace-walk from right to left: tracks in sets of two, each pair composed of a front from one side roughly next to a rear from the opposite side. This is different from the regular walk commonly seen in deer, house cats, dogs, and wild canines, in which the superimposed front and rear tracks from the same side form a zig-zag pattern. In the raccoon trail shown below the details of track structure that were covered in the preceding paragraphs allow us to distinguish front from rear prints. For instance, in the pair of tracks at the upper right the rear print (larger with a broader middle pad) is above and a little ahead of the front print (smaller with a narrower middle pad). The sequence of tracks, starting from the right, is left front, right rear, right front, left rear, left front, right rear. In each pair the rear print is a little ahead of the front. This position isn’t a constant–the relative placement of the two tracks in a pair can vary, but is usually maintained unless the speed or attitude of the animal changes.

With that pattern established, let’s look at an interesting variation. The photo below shows a similar pace-walk pattern, again proceeding from right to left. Although the track details aren’t as clear the relative sizes suggest that the sequence, starting from the right, is right front, left rear, left front, right rear, right front, left rear, left front, right rear. But what are those extra marks? In each of the left rear prints ( the ones in the first and third pair) there’s a deep gouge behind and some light claw drag marks ahead of the actual track. And the right rear tracks (the ones in the second and fourth pair) seem to be connected by continuous drag marks. Grooves and drag marks like these are not usually seen in raccoon trails and indicate that the animal was injured.

This close-up shows the details better.

By the way, you may have noticed a few gouges in the snow in the first pace-walk photo. These aren’t foot drag marks because they don’t connect with the tracks. The best explanation is that the raccoon was carrying something, probably a prey animal, that hung down and touched the snow at every other couplet of tracks. We see this kind of evidence more often in canines and felines, but raccoons will take small mammals if the opportunity presents itself .

Now that we’ve explored raccoon tracks at both detailed and big-picture levels, here’s a final example. When thaws or seasonal changes create seeps in the winter snowpack, raccoons are quick to explore them for edible items. In the photo below a raccoon made two trips between seeps, leaving muddy drips and beautiful mud tracks on top of the crusted snow. The upper trail goes from left to right and the lower one from right to left. In each trail the pace-walk pattern is clear, with the larger rear prints falling slightly behind the smaller front prints. The track details show nicely: the finger-like toes, the narrower middle pads of the front tracks, and the tighter arrangement of the rear toes.

The forest and the trees–both the big picture and the fine details are necessary in tracking. And it’s even more complicated, because there are more than two levels. There are details within details, and larger views beyond large views. The ability to move among many levels is not only essential for effective tracking. It adds depth and excitement to any tracking experience.

Knowing Coyote Tracks

Coyotes are one of our more common predators, but when we find a possible coyote track it can be difficult to identify it with certainty. Could it be a fox? Or maybe a bobcat? And there’s also the possibility of domestic dog. Dog tracks show up almost everywhere and are often mistaken for coyote. In this post I’ll share some thoughts on how to separate coyote prints from some confusing look-alike tracks.

First let’s deal with felines. The bobcat track below is a right front print, oriented toward the top of the frame. Like coyotes, bobcats have four toes and an undivided middle pad, but unlike coyotes (and other canines) bobcat tracks are asymmetrical. They have a leading toe (the second from the left in the photo) and a trailing toe (the right-most one), and the middle pad is canted to the outside. Try this simple test for symmetry: Imagine a vertical line which passes through the center of the track, and then imagine folding the right half of the track over onto the left half. You’ll see that they don’t match up. Now do the same thing with the track in the next photo, a coyote front print, again oriented toward the top of the photo. You’ll see that the right half matches almost perfectly when folded onto the left half.

Both the bobcat and the coyote prints pictured are clear and complete, but because of varying conditions some bobcat tracks–especially rear prints–appear more symmetrical, and canine tracks sometimes have an asymmetrical look. Fortunately, there are other features that can help to distinguish the two. An important feature is the shape of the ridges between the toes and the middle pad. In the coyote track the large ridges between the toes and the middle pad form an X, and at the central point of the X there’s a dome. The major ridges in the bobcat track don’t form an X–they could be described as a squashed H or a partly rotated C-shape with some kinks. Another characteristic to look at is the relative sizes of toes and pads. In bobcat tracks the toes are small in relation to the overall track size, and the middle pad is large. In coyote tracks it’s the reverse: the toes are larger and the middle pad is smaller in relation to the overall track size. In the coyote track there are some delicate claw marks, two close together ahead of the leading toes and a lighter one on the left outer toe. Claw marks are absent in the bobcat photo. If more grip is needed a cat may extend its claws, but claw impressions are much less common in bobcat tracks than they are in coyote (or other canine) tracks. Bobcat prints also tend to be rounder, and coyote prints are more oval or egg-shaped.

Then there’s red fox, whose tracks overlap with coyote tracks at the lower end of the coyote size range. The next photo shows a red fox front print, oriented toward the right side. It’s similar to the coyote track in being symmetrical, and in having the canine X and dome, but there are some features that separate it from coyote. The hair that covers the underside of the fox’s foot shows as striations in the toes and middle pad. This hair gets worn down as the season progresses so it may be less conspicuous in late summer and fall, but in early winter a new growth of thick hair develops. Red fox tracks in snow often have a blurry appearance because of the dense hair. The undersides of coyote toes and middle pads are bare of hair in all seasons, so the toe and pad impressions have smooth surfaces and crisp outlines.

In the middle pad of the red fox print there’s a curved indentation (vertically oriented in the photo) made by a ridge of tough skin that protrudes through the hair. This bar or chevron (present in the front foot and very rarely in the rear foot) is unique to the red fox and, when visible, separates it conclusively from the coyote. In the preceding photo of the coyote track you can see that the bar is absent.

Distinguishing coyotes from domestic dogs can be the toughest challenge. Dogs are so variable that there aren’t any absolute criteria, and many dog tracks are similar to coyote tracks in size. The photo below shows the rear (on the left) and front (on the right) prints of a coyote, oriented toward the right. As in most canines the rear track is smaller than the front. Note the absence of claw marks except for the delicate, closely set pricks ahead of the leading toes of the front foot. Both front and hind tracks are oval in overall outline, and their middle pads are small in relation to the overall track size.

Coyote rear (left) and front (right) tracks

Comparing those tracks with the dog tracks in the next photo, we see some clear differences. The front track of the dog (above) is more rounded and has a larger middle pad. The claw marks in the front print are more robust and are present ahead of all four toes. The rear print of the dog (below) is slimmer than the front but has a conspicuous middle pad, and there are claw marks ahead of all four toes.

Domestic dog front (above) and rear (below) tracks

Dog tracks like the front print below (oriented toward the top) are even easier to identify. The large middle pad and the thick claw marks are strong indicators, but the most striking feature is the spreading of the inner and outer toes. Many dogs have “floppy” feet. Because they are not as active their feet lack the muscle tone of wild canines, and their toes spread more. The inner and outer toes and claws may point to the sides rather than straight ahead. Dogs that get plenty of exercise, like the one that made the tracks in the preceding photo, may not show this spreading.

Varying conditions can affect the appearance of coyote tracks, and this is where things can get confusing. The coyote front track (facing to the right) in the next photo doesn’t look as neat and tight as the coyote tracks shown in previous photos. There are claw marks ahead of all four toes, the inner and outer toes aren’t as tightly tucked in behind the leading toes, and the claw marks are more divergent. This animal was trotting on soft, moist sand, so it allowed its toes to spread slightly for support. But the track still shows the small middle pad and the delicate claw marks that point toward coyote rather than dog.

Faster movement can have an even greater effect on tracks. The print shown below (a front, pointing toward the right) was made by a galloping coyote. The toes are spread, the claw marks are deep, and the middle pad looks asymmetrical. But even this track shows coyote rather than dog features. The claws are sharply pointed and the middle pad is small compared to the overall track size.

There will always be times when making a firm identification is difficult. The tracks may be distorted or degraded, or there may only be partial tracks. But even if we can only come to a tentative conclusion, we can still observe and learn as much as possible. And the more we struggle with challenging situations, the better we will be at knowing coyote tracks when we see them.

Cottontail Rabbits

Familiar animals can be just as interesting as less common ones, and the cottontail rabbit ranks as one of our most familiar–and interesting–creatures. In the photo below (direction of travel from right to left) we see it’s characteristic Y-shaped bounding pattern: two rear tracks even with each other and widely spaced, and two front tracks behind the rear ones, more narrowly spaced with one leading the other. The right front print (the first foot to come down) lies at the right side of the photo and the left front print (the second foot to come down) lies to its left. Farther to the left you see the rear prints which form the diverging branches of the Y. I found these tracks on a highly developed barrier island on the New Jersey coast, probably not a place you would expect to find cottontails. But these animals manage to survive and flourish not just in rural and undeveloped areas but also in city parks, suburban communities, and busy commercial zones.

Although the pattern shown above is very common, it’s not the only four-print arrangement you’ll see. Sometimes a rabbit’s front feet come down together, and when this happens the prints are even with each other and pressed tightly together. Bounding squirrels make groups similar to those of rabbits, but the spacing of the front tracks is different. Whether the front prints are even with each other (the most common arrangement) or whether one leads the other, there is almost always a gap between the two prints. In the photo below the rabbit tracks are in the lower left and the squirrel tracks are at the upper right.

The tracks in the photo below were made by a cottontail bounding in deep snow (direction of travel from bottom to top), and the toes are splayed out in both front and rear tracks. Tracks like these are sometimes mistaken for snowshoe hare tracks because of their larger size.

The feet of both cottontails and snowshoe hares can spread when increased support is needed, but there’s a drastic difference between the two animals. The maximum width of a cottontail’s hind print is about 2 1/2 inches, while a snowshoe hare’s rear track can reach a width of more than 5 inches. The photo below shows a rabbit’s rear foot (seen from the bottom) in a splayed position. Note that the rear foot has only four toes.

In the photo above you can see the thick fur which covers the bottom of the rear foot of the cottontail, and the front foot is just as furry. This is why the outlines of the toes in rabbit tracks are blurry, especially in snow. The next photo shows the right front print of a cottontail (facing to the right) in mud that had dried to a perfect consistency for recording fine details. The toes are visible but not sharply defined, and the texture of the fur can be seen in and around the toe impressions. This photo also shows all five toes clearly–yes, there are five toes on the front foot of the rabbit. But counting toes can be difficult because there are also some pads which look like toes.

To help sort this out I’ve marked the toes and two of the pads in the next photo. The innermost toe is marked Toe 1, following the convention of numbering from the inside of the foot. It’s smaller than the others and often fails to register in tracks. The other four toes are larger and tipped with substantial claws, and the toe arrangement as a whole is asymmetrical.

If you’ve ever had a run-in with a rabbit’s foot you know that, in spite of the furry covering, the sharp claws can dig in quite effectively. Sometimes the claws are the only parts of the foot that make impressions, as in this photo of the right and left rear tracks of a rabbit in a hurry (direction of travel toward the upper right).

In addition to tracks, rabbits leave many other signs of their presence. You may find stems bitten off at an angle like the multiflora rose in the photo below. These angled cuts are characteristic of rabbit browsing and they arise from the anatomy of the rabbit’s jaws.

In the next photo you see the lower jaw of a cottontail with an added line representing a stem or twig. As it takes the stem between its upper and lower incisors, the rabbit positions the stem so that one end passes through the gap between its incisors and its molars. This biting technique results in an angled cut. Deer don’t have upper incisors so instead of making a clean bite, a deer grasps the stem between its lower incisors and its horny upper palate and pulls or jerks to make a rough break.

Cottontails also feed on the bark of young trees and shrubs. Their chews have a rough appearance, with bites penetrating to varying depths, as in the staghorn sumac stem shown below. Chews made by other bark feeders (beavers, porcupines, voles, and occasionally squirrels) are much neater and more consistent in depth of penetration.

Whether it’s bark, twigs, or buds, a rabbit has to ingest a lot of fiber to get at the nutritious living cells in the cambium or in the tiny leaf initials inside buds. The animals boost the nutrition they get from their food by processing it twice. After passing through most of the digestive system, waste is diverted to the caecum where it is fermented to produce additional nutrients. This material is eliminated, usually at night, as clusters of soft globs called caecotropes. We seldom see this kind of fecal matter because the rabbit eats it immediately. After passing through the digestive system again, the waste is eliminated as pellets like the ones in the next photo.

These pellets are dry and fibrous, and are normally scattered irregularly where rabbits feed and move about. Unlike the rounded cylindrical pellets of deer, rabbit pellets are shaped like slightly flattened spheres. Cottontails are now shifting to their summer diet of grasses, forbs, and flowers, but the final result will be pellets similar to those produced from woody food.

The cottontail rabbit is a thoroughly interesting creature with some impressive tools for survival. By observing its tracks and trails as well as chews, scat, and other sign, we can appreciate a creature that is beautifully adapted to its environment.

Raptors on the Hunt

Many birds of prey (especially buteos and larger owls) depend on small mammals for much of their diet, and snow can record dramatic encounters between predator and prey. We see such a story in the image above: the trail of a white-footed mouse ends abruptly where it was snatched by a raptor. The mouse was bounding from the left, and the bird hit it a little to the right of center, leaving a deep depression. Some light striations around the disturbance show where the bird’s wings stroked the snow. It’s hard to say with certainty whether the lucky hunter was a hawk or an owl, but there are a few observations that point to hawk. First, hawks hunt by sight, usually locating their prey on the surface, and that’s what happened in the clash shown in the photo. Owls usually detect prey by sound and often attack prey under the snow surface. Second, hawks tend to carry prey with their talons while owls take the victim in their beaks (although both deliver the killing wound with their claws). The disturbance where the mouse met its end doesn’t show signs of repositioning from talons to beak. A less reliable feature is the sharpness of the wing marks. Owl wing feathers have soft edges designed to reduce the sound of the wings, while hawk flight feathers have sharp, well defined edges. Under ideal conditions owl feather marks are more diffuse than those of hawks, but this feature varies depending on the texture of the snow. The wing marks in the photo are relatively crisp, so at the very least they don’t rule out hawk as the hunter.

In the next photo you see another attack on a mouse. This time the mouse trail enters from the right. The bird also came in from the right, and the deep disturbance where it hit the mouse tells of the violence of the impact. One talon made a gouge in the snow going down into the depression from the right, and both wings made marks on the left side of the photo as the bird lifted off.

A closer look reveals a spot of blood in the depression, visible in the center of the photo. It also looks like there was some repositioning, either in the talons or from talons to beak. The surface attack suggests hawk, but the repositioning tends more toward owl, and the feather marks could have been made by the softer feathers of an owl.

In both of the encounters I just described the hunter succeeded in capturing the prey, but in the photo below you see a different situation. The snow was deep and had an icy crust covered by about an inch of new snow. Sounds of an animal (most likely a white-footed mouse or a meadow vole) under the snow had drawn an avian predator, and the bird had hit the surface hard with its talons. The crust hadn’t yielded, and the only signs of the attack were the impressions of the talons and a few feather marks in the snow. This was definitely an owl since a hawk would not have detected prey hidden under the snow. And this time there’s additional evidence in the form of tracks. The K-shaped talon prints in the lower part of the photo indicate owl–probably a great-horned owl based on the field-and-hedgerow habitat. The feather marks in the upper right part of the photo give some insight into the variation associated with this kind of evidence. The left-most stroke is sharply defined but the ones to its right are less crisp.

In the next photo you see another attempt by an owl, this time in soft snow. Sounds of a small animal under the surface had drawn the attack, and the quarry had been able to evade the owl’s talons at least for a time. I wasn’t able to get close enough to look more closely, so I don’t know who came out on top of that struggle.

Many potential victims are never attacked (consider how often we find the undisturbed trails of mice and voles in the snow), and many that are attacked manage to escape. Estimates of hunting success vary widely, but the highest I’ve found is about 50% from a study of red-tailed hawks in Missouri. Other estimates go as low as 15%. And remember, this is the percentage of actual attacks that result in prey capture. Before an attempt is even made, a bird of prey must spend time hovering, soaring, or perching, in an effort to detect a potential prey animal. There’s a finely tuned balance between predators and their prey. Raptors display impressive hunting skills, and the small animals they prey on have effective ways of evading capture and high rates of reproduction. When we come across signs of a raptor attack we experience a vivid illustration of the complex interplay between predator and prey.