LITMIR.BIZ

      In deep snow, when track details are obscured, the shape of the front wall created by the foot as it enters the snow is especially useful in species identification. Compare the shapes of the walls for the species presented here.

      TRACK WALLS. The walls of tracks created as a foot enters and exits snow are filled with clues for species identification. The back wall found behind the track may hold a metacarpal pad or dew claws on a higher plane than the track. The shape of the front wall is especially important for interpretation. Is the track pointed or rounded? Refer to the illustrations for examples.

      DRAG MARKS. The drag marks found between the tracks are also useful. One method in which gray squirrel and cottontail trails can be differentiated is by studying the drag marks made between sets of four tracks; squirrels tend to drag on the outside edges of the track pattern, while cottontails tend to drag along the median line.

      The shapes of the drag marks and the entrance/exit holes along the surface of the snow are also worthy of study. As an example, consider the shapes left by Bobcats and Domestic Cats when walking in snow. They move in such a way as to create perfect triangles. Or look for the paired lines created by dragging hooves in deer trails.

      Recognizing Track Patterns for Interpretation

      There are also specific track patterns with which you will want to become familiar, so that you can quickly interpret them in the field. With practice you will be quickly able to surmise what an animal was doing from a peculiar series of tracks—sniffing something, pausing, urinating, feeding, etc. Deer “point” to food with a single hoof, many mammals “T-up” when they pause (see later), and Bobcats kick out a hind leg when passing an object they intend to spray with urine. Study the accompanying illustrations to help get you started.

      A feral hog demonstrates pointing; look for the track angling off to the left, and just beyond, the mark of the animal's snout where it rooted and devoured some vegetation in passing.

      Pointing

      Follow a deer trail in good substrate for a short distance, and you will probably find a spot where a front track registers off to the side, an anomaly in an otherwise redundant zigzagging pattern of tracks. This is a front track that was positioned to hold the weight of the head as it reached out and browsed passing vegetation. The leading edge of deer tracks is pointed, and the “arrow” created by this track often points directly to the vegetation browsed by the deer. Pointing can be found on all the ungulate trails, as well as where carnivores step out to investigate a passing scent.

      Sit Downs

      Learn the shape of patterns created by sitting mammals. “Sit downs” are a feature of hunting Bobcat and Cougar trails, which often pause where views of prey are good or in prey-abundant areas. If they wait for a longer period, they are more likely to lie sphinxlike rather than on their sides, as when resting. Canids sometimes sit in areas with wonderful views or when soliciting a reaction from a conspecific. Sitting in both felids and canids is also a sign of curiosity and investigation, because they often sit to watch something with which they are unfamiliar. Sitting is also common at den and rendezvous sites, and near kill sites of larger prey.

      The sit of a Cougar kitten demonstrates the complete hind feet, including the heels, so rarely seen in many moving digitigrade mammals.

      A Bobcat in Santa Barbara County illustrates the “T stop,” as it pauses on a hunting round. The “T” was created when the Bobcat broke its walking pattern and placed its left front foot on the ground adjacent to its right front.

      “T-Trails” and “Box Stops”

      When walking and trotting animals pause momentarily or stop for longer periods, there is often a “T” in the trail. The vertical line of the “T” shape is the typical trail pattern, and the horizontal slash (the “cross” on the T) is created by two front tracks sitting next to each other that break the typical rhythm of footfalls. T-trails are common where animals have heard something in the distance, are pausing to investigate a road before crossing, and have paused at trail junctions. On rare occasions the horizontal slash in the T can be made by two hind feet instead of two front feet; in these cases the animal holds a front foot up and stabilizes itself with the remaining three legs.

      A variation of the T-trail is the box stop, where an animal stops and places all four feet on the ground at the same time. Typically the two corners of the “box” that are part of the normal trail pattern are deeper and easier to see; the two additional “corners” are the extra front and hind tracks that fall outside the normal rhythm of footfalls, and these tracks are often lighter and harder to see.

      A Ringtail in the Sacramento Valley demonstrates the “box stop.” Look carefully to see the lighter prints of the left front and right hind feet.

      The double fronts of a Snowshoe Hare where it paused—one set behind the larger hind tracks, and the second set in front of them.

      Double Fronts

      A pause or stop in a bounding animal such as a cottontail or squirrel is obvious in a trail section where one pair of rear tracks is accompanied by two sets of front tracks. When the animal is bounding normally the front tracks touch down and are followed by the rear tracks beyond them. When it is time to stop, the rear tracks stay put, but the front feet, which have just picked up to allow the rear feet to register beyond them, touch down a second time in front of the rear feet to stop forward momentum. When it is time to move on, the front feet are lifted up and the rear feet push off.

      Determining the Position of the Head

      The position of an animal's head can often be determined by looking for the deepest part of an individual front track; however, large head movements are often more easily determined by studying the overall track pattern. What we describe here is a method to determine the position of the head, and potentially where it was looking or smelling, that works for the slower gaits of walking and trotting. When walking, an animal that shifts to look over its right shoulder will typically influence three pairs of tracks and cause an understep on the side of the body to which it turned. In contrast, when an animal is trotting, the same maneuver often causes a slight overstep, because the momentum of the hind feet continues even though the front foot lands short on account of the shift in the weight of the head. Simple role playing in sand or other suitable substrate will prove out these concepts.

      In both trails the animal is looking to the right. In trail A the animal is walking and turns more to the right, and the turn occurs over a longer duration of time. In trail B the animal is trotting; the look to the right is much shorter and the head is not turned as far.

      As a footnote, there has been discussion in the field about the usefulness of interpreting where a canid is looking by which side of the animal is kicked out during a side trot. However, canids can look wherever they want, regardless of which side the rear end is angled.

       Measuring Mammal Tracks and Trails

      A ruler is a wonderful tool to help you build confidence in your perceptive and intuitive skills. Track and trail measurements aid in identification and are critical for scientific documentation of species in your area; when you are documenting a rare or potentially controversial species, always take

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