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GETTING STARTED

Why Tracks and Scats?

Mark Elbroch

We were faced with a decision at the start of this project. Given the size parameters of this field guide series, we could either present a detailed look at animals' tracks and scats, or use a more superficial approach to a broader diversity of signs—that is, evidence of feeding, beds, and the like. In the end we decided on the former—an in-depth presentation of just several topics. This book is a visual presentation of the tracks, scats, and scent-marking behaviors of California's wildlife.

Interpreting wildlife tracks and signs is challenging detective work; it is an engaging exercise in clear thinking and deductive reasoning. The most reliable tools we have at our disposal to solve the natural mysteries we encounter in the field are animal tracks and scats. Tracks and scats are the foundation blocks in interpreting all indirect evidence of wildlife, and a detailed knowledge of tracks and scats will aid you in interpreting nearly every natural mystery you encounter.

The presentation of this book also includes numerous citations of work completed by others. They may at first seem obstacles to easy reading, but they serve two powerful purposes: First, they are evidence that tracking has forever been integral to wildlife research and monitoring, and second, they are additional resources for you, the readers, to follow up and seek out should a specific topic grab your interest.

There are without doubt numerous methods to speed you along in your study of wildlife tracking. One of us, Michael Kresky, provides a lively description of one method—track journaling—and through this method he has become an expert interpreter of wildlife tracks and signs. Here he shares tips on this process.

Look closely for the California Red-backed Vole remains and the two uric streaks, which are the best evidence that the killer was an American Kestrel.

Honing Your Tracking Skills through Track Journaling

Michael Kresky

Tracking Journal

Track journaling builds your knowledge of tracks and sign by making you observe tracks in close detail; your journal also becomes data, meaning scientific records, of what you discover. The physical act of drawing tracks and taking notes on your surroundings sharpens your ability to see clearly and with greater discernment. While you hover over a set of prints, patterns and shapes begin to emerge. We realize that journaling can be intimidating at first, but keep in mind that each journal is highly personal and evolves over time. Nature Drawing—A Tool for Learning, by Clare Walker Leslie (1995), can guide you in this process.

Author Mike Kresky journals a set of raccoon tracks under a bridge in Santa Barbara, California.

Tracker Louis Liebenberg taking measurements to create an accurate, life-sized rendition of wolf tracks in central Idaho.

When drawing tracks, do not be daunted by the unknown. Often scrutinizing prints and investigating details with poignant questions will lead to tracks revealing themselves. Even when they do not, it is still valuable to draw the track and revisit your journal at later times.

In the field you need a sketchbook or clipboard, pencils or markers, and a measuring device (ruler or calipers). Begin by finding four to six clear prints that you believe belong to the same animal, and choose a single track to draw. Make sure that the track is between you and the light source. Treat the track and the area around the tracks with deference. This preserves the features of the track as well as the story around the tracks.

An effective track journal includes the date, time, weather, habitat, substrate, and wildlife and human activity in the surrounding area. Draw the track, showing the features of the toes and heel pad or claw marks. With a measuring device, note the track's length and width. The most important thing to remember is to be consistent in your practice. For example, when measuring a track, always include the claws in your measurements. In addition, record whether the track is from a front or hind foot, which side of body, and the direction in which the animal was traveling.

Many folks new to sketching in general are unsure how to use shading to convey light or depth. The choice is ultimately up to you. First, try using shading to relay light—how the sun is falling over and/or across the footprint. Second, use shading to relay depth, meaning that you would shade the deepest parts of the footprint the darkest and the shallowest portions the lightest. We would, however, recommend the second method, because shadows created by light sources can distort one's perception of tracks, as we discuss under notes on photography.

An excerpt from Mike Kresky's journals.

Once you have finished drawing the track, step away from it. This gives you a broader perspective, allowing you to see the line of tracks and perhaps discern the gait the animal was using. This perspective offers more information about the interpretation of this animal's behavior. You may notice that the animal was walking, dust bathing, or foraging. After you have drawn an individual track, draw the line of tracks. Measure the distance between the footfalls, again making sure that you are consistent. Although track journaling is a highly focused activity, remind yourself to pay attention to bird song and other animal behaviors. You may be surprised to find that you are near to the animal you are journaling.

Here Mike Kresky has drawn an area map to accompany his journals of individual tracks and trails.

Maps in Your Track Journaling

It is essential to be familiar with the topography where you track. Topographical maps teach us the salient features of the landscape. Specific maps, such as geological, hydrological, or vegetative, provide different perspectives on the natural history of an area. An awareness of topographical information and patterns in your immediate landscape is invaluable for locating ecotones, corridors, and the animals themselves.

In addition to referencing published maps, create your own maps to hone your tracking skills. Start with a map with a one- or two-mile diameter. Then create a map that covers only several hundred feet. Center this map around your set of tracks. Once the tracks have been drawn, fill in the rest of the map with pertinent features such as vegetation, open space, cover, and topography. Then include bird activity, animal trails and sign, and food sources. This practice reveals consistent trends and patterns on the landscape.

Drawing an animal's feet is also incredibly educational. Here Mike has meticulously drawn the feet of a horned lizard.

Field Guides and Nature Documentaries

A collection of field guides is an indispensible tool for finding the answers to many questions that arise from tracking. A diverse library gives you access to information not readily available in the field and builds your ecological understanding. When available, use numerous resources to identify and research a track, feather, or chewed acorn. Cross-referencing builds a more dynamic picture of the specimen you are studying, lending a more objective view. Sources beyond field guides can add valuable information to a reference library. Scientific journals, natural history magazines, news articles, local papers, and the Internet can all broaden your knowledge of tracking and ecology.

While field guides aid in identification of specific species, they also help to develop search imagery for species you have yet to encounter in the field. By casually flipping through the pages of field guides you develop a familiarity with species yet to be encountered.

Nature documentaries expose you to animal movements and behaviors. To assist in your concentration on animal movement, mute the sound track and if available, use slow motion. These movies allow you to watch animals move over a long period of time, thus enabling you to better interpret track scenarios.

In addition, watching animals in videos will help you see how track patterns are made. Watch how an animal's feet fall as it walks, trots, or gallops. Pay attention to the transitions between gaits. You also learn to interpret sitting, foraging, and other behavioral patterns.

Tracking Exercises

Below are a variety of tracking exercises that will help push your tracking skills beyond what can be learned through books and journals.

Mike Kresky's journals are filled with varied and wonderful discoveries, and it is his insatiable curiosity that has made him an excellent tracker.

MAKING SPECIES LISTS A species list compiles all the animals that occur in a given area. For example, if you wonder what mammal tracks you may encounter near Baker, California, obtain a field guide that covers this region, such as Mammals of California by Jameson and Peeters (2004). Flip through every page, and determine via the range map if that species lives in or near Baker. If so, write that species on your species list. Now, when you find a track in Baker, you can be relatively certain the animal is on your list. Organize the list by keeping the animals in their taxonomic families. Other useful species lists to make are trees, birds, plants, amphibians, and reptiles. This exercise prepares you for what you may encounter in the field.

THE SEVEN PERSPECTIVES OF A TRACK This exercise is based on seven separate drawings of a single track and sharpens your observation skills by teaching you to see from different perspectives. Find a clear print: (1) Draw only the outline of the track. (2) Draw the geometric shapes—such as triangles or rectangles—that compose the overall track. (3) Sketch the variation in texture within the track. (4) Next, study the different colors in the track. Even if you do not have colored pens or pencils in the field, take the time to notice the colors in and around the track and note them as best you can. (5) Draw all the edges of the track. Edges include all the areas in and around the track where soft or hard transitions exist. (6) Draw the variation in value within the track, which is the difference in lightness and darkness of the track. (7) Combine all the previous drawings into one.

DRAWING A SCENARIO Find a patch of ground where there are tracks of multiple species. Sketch all the tracks, and notice how they intermingle and overlap. Begin to ask yourself which tracks are older than others. By sequencing the events you begin to see the story unfold. Keep in mind how weather, sunlight, and shade affect tracks. Seton (1958) provides excellent examples of drawing track scenarios.

STAKING OUT A TRACK LINE Begin by finding a series of 20 or more tracks made by the same individual. Then, using wooden skewers or any consistent flagging device you have brought into the field, place one skewer per track. Once stakes have been placed, step back from the trail and observe the revealed pattern. In staking out a track line, you suddenly begin to see how the animal moved across a landscape. You see the gait and how the landscape affected the animal's movement. This exercise is excellent for visualizing how animals move.

Who came first, the Brown Pelican or the human? Journal by Mike Kresky.

LEARNING TO MOVE LIKE AN ANIMAL The more time you spend interpreting the tracks of animals, the more you will recognize the importance of gaits. The following activity is done in conjunction with a field guide or nature documentary that shows the gaits of different animals. Begin by choosing one animal to mimic. Study how that animal walks and where each of its feet land in that gait. Practice walking like that animal so that your own hands and feet fall in the same positions of the animal in the field guide. From there you can work on other gaits of that animal. When you are comfortable with one species, move on to others.

The tank tread made by a traveling Desert Tortoise in the dunes of the Mojave National Preserve in southern California.

BUILD A TRACKING BOX A tracking box can be any size, from a small transportable shoebox to an area large enough for a human to run through. Once the box is ready, fill it with “good” substrate. The easiest medium is play sand purchased at a local hardware store, but you can experiment with local soils as well. Once you have chosen your substrate, tamp or trowel the surface until it is smooth and firm.

Tracking boxes afford many activities for the beginner as well as the more seasoned observer. For instance, place your tracking box near bird feeders or where you know animals frequent. By providing a controlled substrate you can track in any season regardless of circumstances, even if you live in a place where seasonal weather or field conditions make tracking difficult. Once an animal has walked through your box, analyze the tracks as you would in the field. Photography, journaling, and track casts can all be used in conjunction with a tracking box.

The tracking box is also an excellent tool for recording the tracks of specific species. For example, capturing small mammals or live insects and running them across the substrate allows for focused analysis of elusive tracks. To further hone your skills, step beyond the sandbox and into the wild. Smooth out substrates along your daily routes, and monitor the movements of animals in your area.

A composite journal page created by Mike Kresky. Track journals are both educational and beautiful.

Tracke r's Tools: Noninvasive Monitoring

Jonah Evans, Mark Elbroch, Michael Kresky

One of the most attractive aspects of wildlife tracking is that it is noninvasive and provides a rich, detailed record of wildlife presence, habits, and behaviors without the necessity of seeing or handling them. Wildlife tracking provides us cost-effective research methods, and indirect signs allow both hunters and biologists to invest their time in the appropriate place at the appropriate time if they want to catch their quarry.

Below is a brief introduction to several complementary research methods that you might be interested in experimenting with. We highly recommend that you also read Noninvasive Survey Methods for Carnivores by Long et al. (2008), which provides both a more detailed description of all of the following methods and an introduction to the science behind their use in wildlife research and monitoring.

Track Casting

Making a cast is one of the time-honored ways of creating a permanent record of an animal track. Because of the ephemeral nature of tracks in the field, a track cast invites you to revisit tracks over and over again. The three-dimensional aspect of the cast allows for more in-depth analysis of foot morphology. Creating a track cast collection is a tangible way to increase your exposure to animal tracks when not in the field. Track casts are also great for teaching tracking in a classroom or workshop setting.

The simplest and most cost-effective medium to use is plaster of Paris. It pours easily and dries quickly in most weather conditions. Latex, dental mold, or paraffin are used less often but are also effective. The following tips are for making casts with plaster.?

The trail and burrowing mound made by a mole crab. Their trails are common at low tide in the intertidal zone.

MIXTURE In a suitable container (either a plastic cup or Ziploc bag), mix a ratio of about two parts plaster to one part water in a quantity to fill and cover your track. The consistency of the mixture is of greater importance than the exact ratio and should be thick like a milkshake. Thinner, more watery mixtures pick up better detail, but they are more fragile and may have a chalky consistency when dried. We would also recommend that you add the water slowly. You can always add more, but if you add too much, you must hope you have additional plaster in your pack to thicken your solution sufficiently to use.

POURING THE PLASTER Many tracks are delicate, and pouring plaster directly onto the track can damage them. It is a good idea to hold your mixing implement about an inch above the track to break the fall of the plaster, which will then gently fill the track. Once the plaster has been poured, it is a good idea to tap or shake the surface with your mixing implement to encourage any air bubbles to surface and break. This also helps move the plaster into the deepest cavities of the footprint, like the fine marks made by claws.

DRYING Well-mixed plaster on a hot day in the sun and on dry substrate can be dry enough for transport in less than 20 minutes. In cold, wet conditions it may take a few hours. The cast should be fully cured in 24 to 48 hours.

OTHER TIPS A barrier of some kind placed around the track to hold in the plaster can improve the appearance and thickness (strength) of the cast. You can easily make such barriers by cutting out strips from plastic containers of various sizes.

As soon as water is added to plaster, a chemical reaction occurs that releases a small amount of heat. This is problematic for snow conditions, because the plaster melts the snow and misshapes the cast. The solution is a product called SnowPrint Wax, which is a wax that can be sprayed into the track before pouring the plaster. This product prevents the snow from melting.

You may also come across a track preserved in silt mud or clay. You can carefully cut and lift out such a track and preserve it in a dry area. Unlike casting, this preservation technique provides a more pristine first generation of the track; even better, it is not subject to the variables of casting.

Whether you are casting or cutting a track out of substrate, be aware of your impact on the land. Also realize that casting is potentially messy and may involve toxic materials. Clear and concise procedures regarding setup and cleanup of casting are imperative.

Photography

Photographs are a quick way to record tracks and are an excellent tool for learning. Inexpensive digital point-and-shoot cameras are capable of taking decent-quality track photographs and can be carried in a shirt pocket. The drawback of a compact camera is the small sensor, which often equates to high noise levels in low-light situations (common when photographing tracks). High-quality digital single-lens reflex cameras can produce professional-quality images but are bulkier, more expensive, and require more experience and skill to use correctly. Regardless of which camera you choose to carry on your tracking expeditions, your photographs will become a powerful tool for learning and documenting your observations.

Cameras are also excellent tools for recording rare animals. Mark Elbroch snapped this photo with a cheap flip phone to record the tracks of a rare Wolverine atop Castle Peak in the northern Sierras.

Photographs allow you to analyze details that you may have overlooked in the field. By keeping your photos organized and labeled, you can compile a library of different species that you can revisit and compare with each other. You can also enlarge your photos and look for details you may have missed in the field.

Tips for the Field

FILL THE FRAME When taking an image of a single track, position the camera directly above the print and fill as much of the frame as possible. This may require being on your knees and elbows, but photos taken from a standing position rarely have enough detail.

STEADY THE CAMERA Supporting the camera on a tripod is the best method of track and sign photography, because a tripod allows you to use the necessary large F-stops to capture an entire image in focus even in shaded area or low-light conditions. It is possible to take good-quality images by hand when there is adequate light. If you are hand-holding a camera, it may help to stabilize your elbows against the ground or some other object. A general rule of thumb is to use the smallest aperture possible that allows you to use a shutter speed fast enough to avoid blur. Traditionally the slowest hand-holdable shutter speed is the numerical equivalent of the focal length of the lens. Thus, if you are using a 100-mm lens, never use a shutter speed slower than 1/100th of a second.

SHADE THE TRACK Unless the sun is at a very low angle (sunrise or sunset), it is preferable to shade the track. Direct, overhead sunlight removes contrast and may create shadows that distort the shape of the footprint.

Common Poorwill tracks in shade. The penny is ¾ in. (1.9 cm) in diameter and is a useful scale you might have in your pocket.

The deeper, darker impressions in the snow are the trail of a hunting Ermine tracking down a deer mouse that left the smaller, lighter tracks grouped in fours. Photo by Jonah Evans

USE A SCALE Try to place a ruler or other object of known size in the image. In some situations, the absence of a scale can make it much more difficult to identify the track. This is especially important when recording data and documenting the presence of a rare or controversial species.

TAKE SEVERAL IMAGES The great thing about digital cameras is that taking photos is free. Take several photos of each track and vary the shutter speed, aperture, zoom, and other camera settings. When you get home you can select the best image and delete the rest. Taking a few extra photos is well worth the effort when compared to the disappointment of finding that the one photo of a track you took is blurry.

Carnivore Scent Stations

Carnivore scent stations are a fancy name for a human-made track trap. Scent stations were developed by researchers to attempt to maintain a probability of detecting an animal across locations, time, or both. One of the challenges of using tracks in research is that substrates vary, and it is easier to find tracks in some areas than in others. Thus, if few tracks are recorded in an area, this might mean that few animals inhabit the area, or it might be a result of poor tracking conditions.

Scent stations include a scent lure and either an artificial tracking surface such as sand or gypsum, or an enhanced surface obtained by raking an area or sifting local soils. Researchers place scent stations across a landscape and use visitation rates of different species to estimate a variety of parameters including relative and actual abundances. See Long et al. (2008) for a detailed presentation of methods and scientific designs using both scent stations and prepared tracking substrates without baits.

Sooted Track Plates

Sooted track plates are another method developed by researchers to equalize the probability of detecting an animal's tracks. While more difficult to set up than scent stations, they have the advantage of providing a record of the track that can be carried out of the field for further inspection. Track plates come in a variety of forms to suit different species, but the basic principle is the same: an animal is lured across a board or “plate” covered with soot, chalk, or some other powdery substance, and then a sticky paper (contact paper) catches the soot from the bottom of the foot. The resulting two-dimensional tracks can be incredibly detailed or a blur of black dust; they are also very different from the three-dimensional tracks we see in earth and snow. For that reason, we have provided here a brief guide to common tracks you might catch when you do this in California, which begins after page 30. This resource was compiled from three resources: (1) tracks caught as part of a southern Sierra Nevada carnivore monitoring program managed by Rick Truex, wildlife biologist for Sequoia National Forest, (2) the collection of William J. Zielinski and Ric Schlexer at the Redwood Sciences Laboratory of the U.S. Forest Service Pacific Southwest Research Station, and (3) several private libraries, primarily Mark Elbroch's, but with generous contributions by Preston Taylor, Casey McFarland, and Neal Wight.

Track plate methodology has been particularly refined for marten and Fisher detection. Herzog et al. (2009) developed a technique to identify individual Fishers from footprints on track plates and thereby found a noninvasive means of gathering capture-recapture data for quantifying population estimates. Slauson, Truex, and Zielinski (2008) determined that total track length (as defined in the accompanying visual) was an effective method to determine the sex of marten tracks collected on track plates in California. In the Sierra Nevada, the cutoff point is 30.75 mm—larger measurements are males, smaller are females. In the northern Humboldt region, martens are smaller, and the cutoff between the genders was 29.70 mm. Slauson and colleagues (2008) also presented a more complex equation to determine the sex of Fishers from their tracks in California: (1.046 × 13 height) + (1.011 × total length) + (0.361 × 13–14 width). Refer to the illustration to see how to measure these variables. The cutoff point for this equation is 62.17; larger numbers are males, and smaller are females.

Measurements used in determining gender of marten, and one of the measurements needed to determine gender of Fisher tracks as described by Slauson et al. (2008). Note track is not to scale.

Additional measurements useful in determining gender in Fisher tracks on soot plates. For this animal, we calculated 60.93, or female. As described in Slauson et al. (2008). Track is to scale.

For additional information on track plates, see Long et al., Noninvasive Survey Methods for Carnivores (2008), Zielinski and Kucera, American Marten, Fisher, Lynx and Wolverine: Survey Methods for their Detection (1996), and Halfpenny et al., Track Plates for Mammals—A How-To Manual and Aid to Footprint Identification (2010).

Camera Traps

There has been an abundance of relatively cheap remote cameras flooding the commercial market in recent years. Hunters often use them to monitor trails, so that they know exactly when and where large bucks prowl. Researchers use them to document the presence of numerous species, especially rare and elusive ones.

Camera traps are a wonderful complement to traditional tracking skills. They provide a visual confirmation to our interpretations, and provide a way to learn more about tracking. If there is a mystery path created by some animal in your backyard, perhaps a well-placed camera trap can teach you what species created it.

DIGITAL VERSUS FILM The primary disadvantages of digital remote cameras remain shorter battery life and shutter delay, but these are being resolved with each new generation of cameras. The benefits of not needing to pay for film developing, as well as the ability to instantly see photos (and make adjustments as needed), make digital cameras a better choice for most situations.