animal tracking – Page 7 – Linda J. Spielman

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.

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.

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.

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.

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.

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.

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.

A Gallery of Red Fox Tracks

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

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

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

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

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

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

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

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

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

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

A Perfect Storm of Jumping Mice

I guess I was just in the right place at the right time. I was in a part of the western Adirondacks where the soils are sandy–they’re called glacial outwash soils, and they’re a gift from our glacial past. After a day with several heavy downpours the weather cleared, and the next morning I went out to look for tracks. I headed to one of my favorite spots, a sandy truck trail that meanders through a mosaic of wet meadows, marshes, and shrubby uplands. The low spots in the road had filled with water during the rain, but the sandy soil had allowed the pooled water to drain away, leaving perfect tracking mud.

And there were tracks aplenty, mostly small rodents. But not just the usual small rodents–many tracks had the distinctive features of a very special animal. In the photo below (direction of travel toward the top) the five-toed hind tracks are in the upper section, nearly even with each other and set widely apart. Below them are the four-toed front tracks, one leading the other and set more narrowly.

These are the tracks of a small rodent called the meadow jumping mouse. (It’s cousin, the woodland jumping mouse, is restricted to boreal forests and would not have been found where I was tracking that day.) The meadow jumping mouse is pictured in the photo below by Martha Beck (from her blog, Martha’s Blog). This beautiful little creature has a very long tail, large ears and eyes, long back legs, and really interesting rear feet.

Here’s another example of the tracks I found that day. The direction of travel is toward the right, and the front prints (on the left side) are distorted by the impact of landing from a long jump. Nevertheless you can see that the rear tracks (on the right side) are much larger than the front,

especially in this example in which the entire lengths of the rear heels touched down. These long heels are unique to the jumping mouse, as are the long, slender toes. The three central toes are often slightly curved, and they spread more than the corresponding toes of most other small rodents. Another special feature lies in the elongated middle pad area of the rear prints. The inner and outer toes attach considerably behind the area where the three central toes come together.

In the photo below, another one from that amazing day, the elongated middle pad area shows nicely in the left rear print (farthest to the left). The right rear track is on the extreme right, the two front tracks lie between the two hind tracks, and the direction of travel is toward the top. Some interesting details of the front prints can be seen in the right front print (the lowest of the group): it’s canted toward the outside, with the innermost toe pointing up and a little to the left, the toe next to it pointing almost directly upward, the third toe pointing toward the right, and the outermost toe pointing downward. The middle pad area of this track is in the center, and the paired heel pads show at the lower left edge of the print.

Once you’re aware of the critical details, jumping mouse tracks look very different from the tracks of other small rodents. The meadow vole tracks in the photo below, also from that wonderful day on the sand road, are in the same relative positions as the jumping mouse tracks in the previous photo. But the front and rear prints of the meadow vole are similar in size and there is no elongation of toes, heel, or middle pad. The inner and outer toes of the hind tracks show as small ovals on either side of the middle pad area, and the front tracks are only slightly angled.

Although their feet are larger, jumping mice are actually much smaller than meadow voles, but they’re similar in size to another common small rodent, the white-footed mouse. But white-footed mouse tracks are also very different from jumping mouse tracks. The white-footed mouse tracks in the photo below (direction of travel toward the top with hind tracks above and front tracks below) are tiny compared to jumping mouse tracks, and the toes in both front and rear prints are small ovals with no connections to the middle pad. The three central toes of the rear print are close together and parallel with each other, and the middle pads are a distinct series of bumps.

My walk along the sand road that day was a real revelation. Although the drying mud puddles may have been more attractive to jumping mice than to other small rodents, I still have to believe that the abundance of jumping mouse tracks indicated high population numbers. Those scattered, moist habitats were just the kinds of places favored by meadow jumping mice, and the muddy low spots were perfectly situated to capture the animals’ movements. Since jumping mice spend the winter in extended hibernation we don’t have the luxury of seeing their tracks in snow. But a perfect storm of favorable influences created conditions rivaling the best snow tracking, revealing jumping mouse tracks like I’ve never seen them before.

9/26 – I just got a comment from Janet Pesaturo about the range of woodland jumping mice, which is broader than I realized. They’re found in mixed softwood/hardwood forests in temperate zones as well as in boreal forests. Thanks, Janet.

A Closer Look at Deer Tracks

A deer track–so familiar that we may pass it by without paying much attention. But a closer look at a deer track can reveal some unexpected insights. In the photo above the two main toes (called clouts or claws) show as paired depressions separated by a ridge. In each clout the broader rear edges are rounded and the narrower forward ends are bluntly pointed, so the direction of travel is to the right. When the toes are placed close together the way they are in this photo, the overall shape is vaguely heart-shaped.

Here’s another shot of deer tracks, in this case a left front (at the lower left) and a left hind (at the upper right). Front prints tend to be slightly wider and more rounded than rear prints, but the differences between front and rear are not nearly as pronounced as they are in most other mammals.

Now look at the first photo again: it’s actually a rear print superimposed almost exactly on top of a front (which trackers call a direct register). The clue to the double impact lies in the right toe impression: along the leading part of the outer margin there’s a slight crack and a sloping edge. The outer edge of the left clout is more like a vertical cliff. The left outer edge of the rear foot came down even with the left edge of the front, but the right outer edge landed a little inside.

It helps to have a track pattern when wrestling with such matters. The deer in the photo below was doing an ordinary walk (also called the diagonal walk, for reasons connected with the footfall sequence), and it left the zig-zag track pattern typical of the gait. Each “print” is actually made by two feet, first the front and then the rear on the same side.

The next photo shows the double impact more clearly. In each impression you can see part of a front track with a rear on top and slightly behind (know in tracking circles as an indirect register). I call this the ordinary walk because it’s one of the most common gaits of both wild and domestic animals (and because the term is less abstruse than ‘diagonal walk’), but it’s only one of many variations on the walk. The patterns associated with the various kinds of walks vary, but if you can recognize the zig-zag arrangement of the ordinary walk you’re well on your way to understanding these and other gaits.

But how does that pattern come about? Gaits can be hard to understand, especially if you haven’t spent much time watching animals move. Fortunately there are lots of helpful videos available to make up for this lack. Here’s one that shows the ordinary walk really well: https://www.bing.com/videos/search?q=animal+tracking+gaits&view=detail&mid=11CC299AF70EC963C01211CC299AF70EC963C012&FORM=VIRE.

You should go past the galloping dog and the trotting horse and focus on the third sequence, a horse walking in slow motion. You’ll see each hind foot landing in the place just vacated by the front foot on the same side. If you’re curious about the variations I mentioned there are a few later in the video. For example the first cat sequence is an overstep walk, in which the hind foot passes the front foot track and lands just ahead of it.

When a deer is moving faster or more erratically its tracks can look very different. In the next photo of a left rear print, the ridge separating the clouts widens out toward the front. Note also that the two toe impressions don’t look the same: the left one is relatively level but in the right one the tip area and right edge are deeper. This suggests an energetic turn to the right, and this deer was, in fact, making a playful jump to the right.

The deer tracks in the photo below are even less like our idealized image of deer tracks. This animal was galloping from left to right in soft, moist sand, and its feet sank in so much that both the main toes and the dewclaws made deep impressions. These are both left feet, the front on the left and the rear on the right and the differences in the front and rear dewclaws show nicely. In the front track the dewclaws are closer to the main toes and are angled sideways, while the hind dewclaws are slightly farther behind and point more forward. The energetic movement caused the tips of the toes to sink more deeply than the back parts of the clouts. When the feet came up out of the sand the toe tips dragged and parts of the track walls were broken and scattered, adding to the atypical appearance of the tracks.

If we recognize the kinds of differences I’ve illustrated we can go far beyond basic track identification. Track variations can tell us about the movement and energy of the animal, what it was paying attention to, and maybe even why it was moving the way it was.

Black Bear Days

Black bears habitually cover great distances in search of food, moving from one source of edible treasure to another throughout summer and fall. The animals often find our trails and primitive roads to be convenient travel routes, and the muddy spots that develop in rainy weather are an ideal medium for capturing their tracks. I recently found these tracks on a forest trail used by snowmobiles and ATVs. The direction of travel is to the left; the left rear print is at the lower left and the left front is at the upper right. Bear tracks, especially those of the hind feet, may remind you of barefoot human tracks, but beware–the largest toe lies on the outside of a bear’s foot rather than on the inside.

But even when there’s no mud, you can learn a lot about the daily lives of bears by observing the sign they leave. Bears love fruits of all kinds. The bear that climbed the shadbush trees pictured below probably knew they wouldn’t support its weight. But no matter, it was easier to eat the berries while standing on the ground anyway.

When apples start to ripen, bears climb the trees to get to the sweet fruits in the highest branches. The gouges in the photo below show how the bear’s claws slipped downward before they caught firmly enough for the animal to move farther upward. When feeding on apples or other fruit, bears sometimes break branches and leave them hanging in the tree or on the ground below. Smaller animals like raccoons and gray foxes also climb trees in search of fruit, but their claw marks are narrower and do not show the separation distances of one inch or more that are typical of adult bears.

Insects are a much sought-after source of protein, and bears dig up nests and tear open logs and stumps to get at grubs and larvae. Even whole tree trunks are not too much for a bear’s power. The snag in the photo below was dismembered by a bear. No other animal would have been able to break out the large sections of wood and scatter the fragments in several directions.

It’s not always possible to determine exactly what a bear was after, but in the case of the tree above the evidence–the remains of carpenter ant galleries shown in the photo below–was still present in the large wood sections. Carpenter ants don’t actually eat wood. Instead they use trees as nest sites, and the tunnels and galleries they create in dead wood serve to house their eggs and larvae. Once an ant nest is exposed by a marauding bear the adult ants flee, but the eggs and larvae, and probably a fair amount of wood, are scooped up and consumed en masse.

Bears are also concerned with the movements of other bears, and they keep tabs on each other through various kinds of messages. The bites which decorate the balsam fir shown below were made by a bear standing on its hind legs. To leave such marks a bear sets an upper canine tooth in the bark and draws the lower canine in. This leaves dot-dash patterns like those to the left of the debarked area. The debarked area itself resulted from repeated biting, and the weathered appearance of the exposed wood tells us that the marking had been going on for a number of years when the photo was taken. Such marks may be visible to bears at close range, but more importantly, they hold the scent of the animal which made them, and bears are famous for their keen sense of smell.

This was a large tree, and it must have been a magnet for every passing bear. It stood about twenty feet off of a seldom-used hiking trail, and between the trail and the fir tree there was a narrow passage with distinct step spots. These step spots were created when approaching bears walked toward the tree with an exaggerated swagger, planting each foot deliberately as if they wanted to leave as much evidence of their visit as possible. In the photo below the step spots show as brown areas of bared soil.

Bear sign, and sometimes tracks, can be very abundant, but unless there’s an artificial attractant (such as garbage or handouts) they’re seldom seen. But fortunately for us their strength and resourcefulness can be observed in their tracks and sign. We can even read, albeit on an elementary level, their messages to each other.

Turtles on the Move

One spring a few years ago, as I wandered along the banks of my local stream, I came upon a wood turtle engaged in digging a hole in a gravel bar. She was preparing to lay eggs, and she seemed to be laboring mightily. The spot was very rocky and she wasn’t making much progress.

Finding a turtle in the process of egg laying isn’t that common, and wood turtles themselves are scarce, so this was a very exciting find. But not wanting to create any more difficulty for her, I took a few photos and left. I don’t know whether she succeeded or whether she gave up and looked for an easier location.

Turtles usually find places that are more favorable for digging, like the sandy spot in the photo below. But the eggs in that nest didn’t mature. When young turtles hatch successfully they break out of their shells underground and make their way to the surface without creating much disturbance. The presence of signs of digging and shell fragments on the surface means that the nest was raided and the eggs were eaten, perhaps by a raccoon or a fox.

Although late spring and early summer are the peak times for reproduction, turtles may continue to mate through the summer and even into the fall. Pairing up and egg laying generally involve a lot of travelling, and these wide-bodied and low slung animals leave distinctive trails. The trail below was made by a diamond-back terrapin moving from bottom to top. Each line of impressions was made by the front and hind feet on one side, and the small front tracks alternate with the larger rear tracks. Between the two strings of prints you can see disturbances made by the dragging plastron, and at the very bottom of the frame there’s a small tail mark.

This turtle was walking, but the pattern looks very different from the patterns we see in walking mammals. That’s because the terrapin’s wide body and short legs prevent it from walking the way most mammals do. The turtle was doing an understep walk, the rear foot consistently coming down behind the spot where the front that moved forward just ahead of it was placed. The rear feet touched down about midway between the last front track and the one before that, so the spacing between prints is roughly even.

Here’s another turtle trail, this one made by a painted turtle moving from top to bottom on hard sand. The tracks consist mainly of claw marks, and they lie in sets of two, each set made up of a front followed by a rear. Both front and rear feet have five claws, but the front prints turn inward while rear prints point straight ahead. The gait in this photo is also an understep walk, but the hind tracks are closer to the front tracks than in the preceding example. Although the relative positions of front and rear prints can vary, turtle trails are always variations on the understep walk.

The trail in the photo below was made in dry sand, and the dragging plastron made a wide, smooth mark between the two track lines. Clear prints are not present, and it’s not obvious which way the turtle was going. Two kinds of evidence suggest that the direction of travel was right to left. First, the plastron drags seem to have smooth slopes on their right sides and steep edges on their left sides. And second, the deep holes made by the feet have drag marks pointing to the left.

Turtles are on the move, and their journeys can take them through a variety of habitats. Any area of sand, silt, or mud might show their unique parallel strings of prints and, sometimes, whimsical designs. So when you get a chance, take a detour and check out that patch of sand or muddy shoreline.

Avian Woodworkers

Woodpeckers, like other birds, are raising families at this time of year, and they’re consumed by the need to provide food for their young. Because they find much of their food in the bark and wood of living and dead trees, their feeding sites are usually easy to find. The first clue is often a pile of wood chips scattered around a tree base, like the accumulation at the base of the beech tree shown below.

This tree was alive but just barely–the cankers on the trunk tell us it was infected with beech bark disease. The two excavations visible in the photo, plus many more higher on the trunk, were the sources of the widely scattered debris below.

If your timing is good you may find woodpecker scat among the chips. Here’s a close up–this scat was about 1/4 inch in diameter, contained insect exoskeletons, and had some white uric acid on the mostly black surface. Woodpecker scats are delicate and disintegrate when they’re rained on, so you’re only likely to find them in fresh debris piles.

The cavities below were made in a Norway spruce that was very much alive. New holes are often circular, but as they’re enlarged they become elongated and sometimes connect to form long troughs.

So what exactly are woodpeckers that attack trees eating? Contrary to what you might think, they aren’t eating wood! The photo below shows a close-up view of an excavation. Deep in the recesses of the hole the wood is partially decayed, and you can see that it’s honeycombed with tunnels and chambers. These are the galleries of carpenter ants. They’re actually nests rather than feeding sites–carpenter ants range widely on plant surfaces and on the ground, eating other insects as well as sap and nectar. Both living and dead trees may house carpenter ant colonies, and there could be thousands of ants in one tree, so for a woodpecker it’s well worth the work of excavating holes to get at them.

The photo above also shows cuts and grooves made by the bird’s beak as it chiseled the wood away. These beak gouges are large, up to one half inch wide. The pileated woodpecker, the largest and most powerful of our woodpeckers, was responsible for all of the examples shown above. Only a bird this size could make such large holes, not to mention create such wide beak gouges and leave such large scat.

Although smaller woodpeckers can’t produce the same kinds of massive excavations, they still manage to find plenty of food in the bark and outer wood of trees. Hairy or downy woodpeckers searching for wood-boring grubs removed patches of bark from this hemlock tree.

And the dead maple shown below was also mined for wood inhabiting insects. It’s covered with pockmarks made by smaller beaks, as well as some larger gouges, so it was probably a multi-species feeding site.

Wood, whether living or dead, may host many different types and sizes of insects, including the wood-boring larvae of beetles and moths, insects that nest in wood, predatory arthropods that feed on other wood-inhabiting insects, and creatures that simply find shelter in cracks and crevices. Thanks to this diversity, wood is a rich source of food for many different birds.

Red Squirrel Housekeeping

The snow is gone and leaves have not yet filled in the forest canopy, so it’s a great time to look at red squirrel middens. Conifer seeds make up a large percentage of the red squirrel diet, and the animals spend lots of time eating or collecting conifer cones. To get at the seeds a squirrel holds a cone in both front feet and, starting at the bottom, chews off each scale and eats the exposed seeds, spinning the cone as it works its way toward the tip. This is done with typical red squirrel energy, and the scales seem to fly out at blistering speed. The scales and cone cores accumulate around or below the feeding station, and the resulting piles of debris, called middens, can be quite sizable. The mounds in the photo contain mostly the cores and scales of Norway spruce cones. Middens this large must have accumulated over a number of years, probably during the residence of several different animals.

The hole just below the trunk of the closer tree is an entrance to an underground space where cones were stored. These food caches are often located in the spaces around the roots under the middens, but may also be in rock cavities, log piles, or even human structures. They are generally underground where the high humidity prevents the cones from opening.

Red squirrels depend on stored conifer cones for survival over the winter. In late summer and early fall conifer stands resound with the sound of objects hitting the ground as the animals nip the cones in the tree tops. Once a good supply has fallen, the squirrels descend and carry the cones to their underground storage spaces. It’s this habit of creating concentrated supplies in a limited number of locations, called larder hoarding, that allows the animals to inhabit boreal forests with long, snowy winters. Imagine the effort that would be involved if, like gray squirrels, red squirrels had to dig down through a deep snowpack to retrieve each individual food item. With its food stored in larders a red squirrel merely needs to maintain tunnels leading from the surface to the ground-level entrances.

Middens are usually located at the bases of the trees which provided the cones, indicating that the squirrels bring cones up from storage to perches higher in the tree to feed. In the photo above you can see a Norway spruce with several branches (dead but still strong enough to support a squirrel) which could have served as feeding perches. These branches, or ones nearby, are often marked by the squirrels. One such branch is shown in the photo below. The shot was taken from directly above the branch. You can see some partly eaten spruce cones on the ground below in the upper part of the photo, and the dark tree trunk in the lower right-hand area. The branch itself is liberally marked with the fresh gouges of red squirrel incisors, and there are a few older gouges from previous years. The scent compounds left in the wood would establish the resident squirrel’s ownership of that particular real estate.

Middens tell us how much red squirrels depend on conifers for their winter food supply–and it’s not just Norway spruce. Where pines, hemlocks, firs or other spruce species are more common their cones provide the bulk of the winter diet, and similar middens can be found.

In the mixed forests of central New York, middens tell us about the non-coniferous foods that red squirrels also make use of. In the photo above butternut shells with typical red squirrel entry holes are mixed with the spruce scales and cores. I’ve also found the opened shells of walnuts, acorns, and hickory nuts in red squirrel middens. And occasionally a bone fragment, with telltale incisor gouges, sits atop a midden. Red squirrels, like other small mammals, need to boost their calcium intake by chewing on bones, and a familiar feeding perch makes a fine location for a dose of minerals.

Spring Fever among Woodchucks

If you think you have it bad, just consider the woodchuck. The males emerged from hibernation weeks ago only to find the ground covered with snow. There wasn’t much to eat, and the weather wasn’t very spring-like. But no matter–they were more interested in procreation than food or comfort, and they spent their time searching out burrows occupied by females. Upon finding a receptive female the male entered the den and copulated with her, then moved on in search of another one. With nothing much to eat the roaming males, which may have dropped up to 1/3 of their body weight during hibernation, lost even more body mass. Meanwhile, the female woodchucks remained underground and got a few more weeks of sleep.

This delayed emergence is important because, like the males, female woodchucks have already lost weight during hibernation and losing even more would impair their ability to give birth to healthy young. Their appearance above ground coincides with the onset of new spring growth and their condition improves rapidly.

I found the den pictured below in early March. A few inches of new snow covered about a foot of denser old snow, which made for nice tracking. There weren’t any tracks beyond those shown in the photo, so it looked like the animal came out, took a look around, and then went back into the burrow. The mud-on-snow tracks are remarkably clear–check out the right front print just to the right of center.

Finding such unmarred tracks around burrows becomes less likely as the season advances and the animals make more forays to and from their winter refuges. The photo below, also from early March but taken a few years ago, shows the muddy and partially melted evidence of several trips. In both of these cases the weather was still pretty cold and there was a substantial snowpack, so these were most likely males in the throes of spring (or rather mating) fever.

As winter loosens its grip woodchuck tracks start becoming more widespread in fields and forest edges. In the photo below the direction of travel is from the lower left of the frame to the upper right, and the impressions form a zig-zag pattern. Each angle of the zig-zag is composed of two

tracks, the rear positioned roughly on top of or close to the front track from the same side. These are the characteristics of the indirect register walk, the woodchuck’s most common gait. Starting from the lower left, the sequence in the photo above is right hind on right front, left hind on left front, right front with right hind just ahead, left hind on left front. To the right of the first set of left front and hind there are some gray squirrel tracks heading in the opposite direction.

By the way, woodchucks are also known as groundhogs, but I prefer the name woodchuck, because the word derives from one of its Native American names. Woodchucks weren’t as common in pre-colonial times as they are now, but their populations would have been concentrated around cultivated fields so they would have been familiar to Native Americans. They still thrive in agricultural landscapes, and are sometimes seen as pests. From an ecological point of view they are actually beneficial. Woodchuck excavations help to turn over and aerate soils, and their burrows provide homes for many other animals.

The photo above shows a burrow I found after a very cold night. Rabbit tracks led both in and out, but this hole wasn’t dug by a rabbit. Unlike European rabbits, which construct extensive tunnel systems called warrens, our cottontails don’t dig burrows. They get along just fine without underground housing, unless it’s very cold. When that happens they find shelter, and that shelter is often a woodchuck burrow.

An Encounter with a Fisher

Sightings of wild mammals are generally rare, and when they do occur it’s usually just a quick glimpse of the tail end of the animal as it flees at top speed. So my recent encounter with a fisher was doubly unusual. I was walking downhill on a sloping section of forest road (Hammond Hill Road in Hammond Hill State Forest for those who know the area). That part of the road is straight so I could see pretty far down the hill, and I suddenly realized there was a dark animal moving around on the road far below. I froze, not sure at first what kind of animal it was and hoping it wouldn’t realize I was there. It didn’t–in fact it actually began coming up the hill toward me. As I got a better view of its elongated body, short legs, and long fluffy tail I realized it was a fisher. I watched as it moved in a completely relaxed manner–apparently unaware of my presence–and marveled at its beauty. I was afraid if I made a move to get out my camera the fisher would take off, so I didn’t dare try for a photo. But here’s a good photograph of a fisher obtained from the Vermont Center for Ecostudies (https://vtecostudies.org/blog/walk-with-the-fisher-on-outdoor-radio/).

Photo courtesy of the Vermont Center forEcostudies

The fisher continued to move uphill in my direction at a steady bounding gait, with an occasional pause to look around. When less than 50 feet separated us, it suddenly realized I was there. It stood up on its hind legs, stared at me for a few seconds, and then bounded off into the trees.

Of course I immediately went to look at the tracks. Because the snow was dry and fluffy most of the prints weren’t clearly defined, and the cloudy conditions made things even harder to see–and nearly impossible to photograph. But there was a spot farther down the hill where the snow was firmer and the track details showed up better. A set of four prints from that part of the trail is shown in the photo below (direction of travel from right to left). The pattern

Track sequence, starting from the right: right front, left front, right rear, left rear.

resembles the bound of a cottontail rabbit: the two front tracks are narrowly set behind the rear tracks, and one (the left front) leads the other. The rear tracks are more widely separated and almost even with each other. Typical mustelid structure shows in the prints: the five toes are arranged in a lopsided crescent and the middle pads form a smaller crescent behind the toes.

That was only one of several different gait patterns I saw as I backtracked along the fisher’s trail. In true mustelid fashion the animal had been very flexible in the way it placed its feet. Rather than showing the rather poor photos from that day I’ll illustrate two of the variations I saw with shots that I took on other days (the direction of travel again is from right to left). As in the opening shot the four tracks in the photo below are well separated, but the rear prints are staggered rather than even with each other, and one is positioned slightly behind the leading front print.

Track sequence, starting from the right: right front, right rear, left front, left rear.

In the next shot the left rear foot came down on top of the left front, leaving a pattern that looks at first like there are only three tracks. But in the heel area of the middle impression there’s an inner ridge and a wider area of disturbance to its left, showing that two feet did actually land there.

Track sequence, starting from the right: right front, left rear on top of left front, right rear.

In addition to those two there were other variations–changes in the leading front or rear foot and slightly different placements of the second and third feet to hit the ground–but to my eyes the fisher’s bounding movement appeared to be uniform and unvarying. Except for momentary pauses it moved steadily uphill with the gently arching leaps that are so typically mustelid. One difference did stand out, and that was a variation in the leap lengths: the four-print patterns that matched the one shown in the first photo were separated by slightly longer distances than the patterns shown in the second and third photos. The fisher apparently wanted to move faster, and I suspect that the more even placement of the rear feet in the first photo delivered more power and enabled longer leaps. But there were many variations in the patterns that didn’t involve any changes in leap length, so there must be other factors that cause a fisher to vary the way it places its feet. I can only imagine the subtle interactions that go on between the animal and its surroundings. I hope that with further study of fisher trails, and maybe even some additional encounters with fishers, I’ll be able to understand more of the puzzle.