Tag: fox

Leafy Disturbances

Leaves: at this time of year the woody plants are bare of leaves, and last summer’s weather-beaten foliage covers the forest floor in all directions. Is there anything we can learn about the lives of animals from this seemingly mute carpet? The answer is a resounding yes! In the photo below we see a well-used deer trail. The dry, undisturbed leaves on either side contrast with the darker, disturbed texture in the trail. Even when it’s compressed, deciduous leaf litter is harder to walk on than pre-existing trails, so deer often create runs between bedding and feeding areas.

It’s not as easy to detect deer tracks if they’re not on well used trails. The next photo shows an individual deer track, orientated toward the right. The hoof pressed down into the leaf litter and the outer rims left curved depressions on the top layer of leaves. But if you just were hiking along, would this print attract your attention? Probably not. To find individual deer prints it helps to study areas where the animals have spread out from obvious trails into feeding or bedding areas.

Fall is mating season for whitetail deer, and back then the males were spending most of their time trying to attract females. Bucks made scrapes on the ground and left their scent at the site by depositing urine in the scrape. They also left their olfactory signature by rubbing their foreheads and faces on overhanging branches. The signs of these mating rituals often last into spring. In the photo below (taken a few weeks ago) you can see a scrape just below an overhanging branch still bearing a few leaves.

A close-up of the scrape has a weathered look but still shows signs of deliberate disturbance.

Deer aren’t the only animals that clear leaves. Turkeys sweep leaves aside as they search for insects and other edible tidbits beneath the leaf litter. In the photo below debris lies on top of the leaves at the bottom and lower right, showing that the turkey stood facing the upper left as it tossed the leaves backward. By using both of its feet the bird created a roughly triangular cleared patch.

But turkey feeding scrapes aren’t always triangular. In the next photo you see one that’s more irregularly shaped. There can be a lot of variation in the shape of the cleared area and the amount of displaced debris.

Buck scrapes and turkey scrapes can be quite similar, but there are ways to tell them apart. First, deer mate exclusively in the fall, so buck scrapes discovered in the spring will show signs of several months of weathering. Turkeys make feeding scrapes in all seasons, so at this time of year they range from fresh to weathered in appearance. Both of the turkey scrapes shown above are relatively recent, while the buck scrape in the preceding photos had been created about five months earlier.

Another difference between deer and turkey scrapes is their distribution. An individual buck usually makes a limited number of scrapes, almost always associated with overhanging branches, in an area he is patrolling. Turkeys usually feed in groups, and they go wherever the eating is good, so turkey scrapes are likely to be more numerous and scattered more irregularly.

Squirrels also disturb leaves. The next image shows a cleared area at the base of a tree. When I found this I wondered if it was the result of frequent use as a take-off spot by squirrels.

To check, I looked at the bark above the cleared spot (shown in the next photo) and saw that the moss and outer bark had indeed been abraded. I’m attributing this to squirrels, the most common tree climbers, but I can’t entirely eliminate the possibility that it was a raccoon. Other climbing animals are unlikely because they are less likely to climb one tree repeatedly.

Like turkeys, squirrels search for buried nuts and insects, especially in the spring when stored food supplies may have run out. Both red and gray squirrels obtain these items by digging small holes. In the next photo you see a dig made by a squirrel. Debris from the hole can be seen below and to the right, so the squirrel must have been facing the upper left as it dug.

Here’s another image of a squirrel dig, this time in a layer of pine needles. If the buried object was a nut or acorn the hole usually retains a firm impression of the object. In the digs shown in both photos the bottoms of the holes were loose and irregularly shaped, so the food items were probably insects.

Deer also dig at leaf litter in search of nuts and acorns. White oak acorns are consumed by many animals and birds, so they disappear soon after they drop. The higher levels of tannins in red oak acorns make them less palatable, so they mostly lie uneaten on the ground until soaking rains leach the tannins out. But once they’re more digestible red oak acorns are sought out by many animals, including deer. Where red oaks are the predominant oak species, areas of churned up leaves like those in the next photo (taken last December) can be found in late fall and winter. You can see fragments of acorn shells and meats the deer dropped as they chewed.

If there’s a heavy, wet snowpack in late winter that compresses the leaves, deer feeding areas may be hard to recognize by the time spring arrives. But after winters with little snow like the one we just had, the signs are evident. A few weeks ago I went back to the area where the photo above was taken to see what it looked like. In the photograph below you can see that the leaves still lie loosely in piles and windrows. There aren’t any acorn fragments to be seen–if the deer weren’t interested enough to gather them up they would have been eaten by other animals like squirrels, mice, raccoons, crows, foxes, or even fishers. You’re not likely to find fresh evidence of deer foraging for acorns because the fall crop has been mostly consumed.

Areas where the leaves were not churned up by deer (or turkeys) look very different. Fall rains and the little snow we did have were enough to flatten autumn’s leaf fall into a smooth-looking mat like the one pictured below.

Some places cleared of leaves are more mysterious . Is this the work of a deer? Or a turkey? Actually, neither.

When you see the same spot in the more distant shot shown below, you’ll see what moved the leaves: water. The close-up above comes from the area in the lower left quadrant of the distance shot below. During a heavy rain, water flowed down the trail on the right and spilled over the edge into the leaves. As the water rushed downhill it made channels in the leaves and moved them into heaps along the edges.

Leaves have stories to tell, and to understand them we need to get familiar with undisturbed leaf litter. Once we begin to pay attention to leaves, and to places that depart from the unaltered baseline, we’ll have a whole new window into the lives of animals.

Dog Tracks: Common But Not Always Commonplace

Our familiar companion animals leave their tracks everywhere, and we see them so often we may find ourselves giving them only superficial attention. But if we look more carefully we may be surprised at how much they have to teach us. Dog tracks can show us the traits that are shared among dogs and their wild relatives, and they can also reveal the remarkable range of variation that could only belong to a long-domesticated animal.

The photo below (direction of travel toward the top) illustrates a number of core features that are shared by dogs, foxes, coyotes and wolves. The front track (lower left) is larger than the rear track (upper right). Both front and rear tracks have four toe impressions, and a single smooth middle pad. The tracks are symmetrical, meaning that if an individual track were divided down the middle and the right half were folded over onto the left half the two halves would superimpose almost perfectly.

There are a few additional traits in these prints that are shared among some–but not all–dogs and their wild relatives: The overall outlines of both front and rear prints are oval, the toes are held tightly together, and the claw marks point straight ahead. The larger ridges between the toes and the middle pad form the celebrated canine X, and the center of each track is occupied by a rounded dome or plateau. But although the tracks are roughly coyote sized, we see several additional traits that indicate dog rather than coyote. The claw marks are wide and deep, the middle pad of the front print is large compared to overall size of the track, and its trailing edge is rounded.

A comparison between the dog tracks above and the coyote tracks in the next photo will highlight the differences. (The coyote front print is below and a little ahead of the rear, and the direction of travel is to the right.) Like the dog tracks, the coyote prints are compact, with oval or egg-shaped outlines and tightly held toes. But some of the claw marks are missing, and those that are visible are delicate rather than robust. The middle pad of the front track is relatively small, and its trailing edge is concave.

The dog front track shown in the next photo is even more of a departure from the two preceding illustrations. Instead of being oval the print is round in outline, and the toes, especially the inner and outer ones, are widely spread and angled to the sides. The upper arms of the canine X seem to have been pressed apart, and there’s a curved ridge instead of a dome at the center of the track. Like the previous dog tracks, the print in the photo below has wide claw marks and a large middle pad. A track like this is easily recognizable as dog.

The photo below shows another dog track variant. The overall outline is rounded–in fact the print is a little wider than it is long. In contrast to the triangular middle pads of the previous dog tracks, this print has a trapezoidal middle pad with a broad leading edge. Instead of an X the internal ridges form a distorted H shape, and there’s a horizontal ridge rather than a dome in the center of the track. The absence of claw marks is unusual for a dog print. This is the kind of track that might be mistaken for a feline–a house cat, bobcat, or even a cougar depending on the size of the print. But there are clues that indicate dog, and they become obvious if we look at a true feline print.

The photo below shows the right front track of a bobcat. If we test for symmetry using the folding test described in the second paragraph, we can see that the dog track above is symmetrical and the bobcat track below is asymmetrical. There’s a leading toe (second from left) and a trailing toe (rightmost) in the bobcat print, and the middle pad is canted to the right. Instead of the canine X we see an angular C-shaped ridge that is also canted to the right. Another important feline trait is the contrast in size between the large middle pad and the small toes.

Wild canines have a way of placing their feet quietly, without tension or unnecessary movement. Dogs, on the other had, often express slight jiggles or shifts in the movements of their legs, and the difference can sometimes be seen in their tracks. In the photo below you see two dog tracks (in the upper left, the front a little below and behind the rear) and two coyote tracks (the front in the upper right corner and the rear just below the two dog tracks). Displaced bits of snow lie inside and around the edges of the dog tracks, while the coyote tracks have mostly smooth floors and margins. The best way to see the action that produces this kind of difference is to watch a dog walking or trotting directly away from you. You may see subtle shifts in the body or slight wobbles as the legs contact the ground.

Dogs lead easy lives compared to wild animals, and this often shows in the trails they make. The tracks of three creatures can be seen in the photo below. A dog meandered from top left to bottom right, leaving two partly superimposed tracks in the upper left corner, two tracks close together midway down the left side, and two more widely separated tracks at the lower right. A coyote trotted from top to bottom leaving smaller direct register prints, one between the dog tracks in the upper left and another at the lower left. And my boot tracks can be seen to the right of the dog tracks.

Wild creatures cannot afford to waste energy. There are exceptions: young animals play, and during mating season mature animals can make some wacky moves. But the business of survival demands efficiency of movement. Dogs, on the other hand, can expend energy without the pressure of finding their next meal. The coyote in the photo above had a destination in mind and moved with purpose. The dog was well fed and carefree, and counted on finding food and shelter when it got home. And I was focused on the story those tracks told about the lives of dogs and and their wild relatives.