Tracking Mammals

Mammals are among the most exciting types of wildlife to see, but also some of the most difficult.  Far less numerous than birds and often exhibiting secretive or nocturnal habits, many groups of mammals are rarely encountered in the wild.  Observant naturalists are far more likely to encounter signs of a mammal's presence than the mammal itself, the most obvious of which are tracks, scat and fur.  But more subtle clues may be discovered as well, such as dens, nests, burrows or bedding areas, as well as evidence of feeding, like chewed bark, twigs or pinecones.  All of these are forms of mammal "sign" and are good indicators that the mammal which left the sign is or has recently been present in the area.  

I like to think of mammal signs as similar to bird songs and calls: proof of a species' presence in the area, and valuable for research purposes, even when I'm unable to get a look at the animal itself!

Sure, seeing the animals is always more exciting, but studying mammal tracks can be a fun way to discover species of mammals in the area that may otherwise go undetected.     

Common Raccoon

The small, human hand-shaped tracks of the Common Raccoon, pictured above, are one of the easiest (and most abundant) mammal tracks to find in North America.  Raccoons inhabit a wide variety of habitats, included urban and suburban areas, so their tracks may be found just about anywhere.  They also spend a lot of their time along bodies of water, where soft mud is likely to leave clear tracks.  Notice that on the tracks of raccoon, the whole digit leaves an imprint, rather than just individual toe pads.

Striped Skunk, front foot, San Joaquin River NWR

Striped Skunk tracks, pictured above and below, are similar to those of the raccoon, but with well-defined long claw marks on the front feet that tend to angle slightly inward.

Of course, another excellent though invisible sign of the presence of skunks is their distinctive and pungent odor!

When photographing tracks, including an object for scale is essential.  In a pinch, a pencil or pocketknife will do the trick, or even your own hand or foot.  Ideally, the object would be a small ruler, but I rarely remember to carry one of these with me in the field!

Striped Skunk, back foot (partial), San Joaquin River NWR


Soft mud is one of the best places to look for tracks, so keeping an eye on the ground along bodies of water or after rain can be productive.  Mammals are often drawn to water, so be sure to spend time scanning the edges of streams, ponds and even puddles.  

The Bobcat tracks pictured below were found after rain, in the soft gravelly clay between the tire tracks on a little-used dirt road.  During the dry months, this ground will be rock-hard, and passing mammals won't leave any discernable tracks at all.

The two best ways to distinguish between feline and canine tracks are the overall shape of the track and the presence or absence of toenail marks.  Feline tracks (housecat, bobcat, lynx, mountain lion) are round in their overall shape and lack toenail marks, while canine tracks (domestic dog, fox, coyote, wolf) are oval in their overall shape and will show defined toenail marks.  

Bobcat, Grasslands of Eastern Stanislaus County


The River Otter tracks below weren't the only signs of otter presence in the area: mud "slides" leading down the adjacent bank into the creek showed plainly where otters had been repeatedly entering and exiting the water.  

North American River Otter, San Joaquin River NWR


Freshly fallen snow is another great substrate on which to look for tracks.  When attempting to identify mammal tracks, be sure to take a look at multiple sets of tracks, if you can, and note the animal's gate.  The pattern and placement of front and hind feet can tell a lot about a species identity.  

For example, the tracks of walking foxes, coyotes and wolves usually "register," or show the track of the hindfoot directly on top of the forefoot; this is not the case in domestic dogs, where tracks of hindfeet and forefeet can be seen one just slightly in front of the other.

The bounding gate of tree squirrels, shown below, leaves a distinct impression in which the hindfeet register in front of the forefeet.  

Tree Squirrel (likely Western Gray Squirrel) bounding, Twain Harte, CA


American Black Bear tracks are unmistakable, and here the forefeet and hindfeet can be clearly distinguished.  Notice the bear's ambling gate where the animal shuffled across an inch of fresh snow.

Also notice my size 9.5 boot at the bottom left of the photo for a size comparison!

American Black Bear, Twain Harte, CA


Identifying mammal tracks takes a great deal of study and practice - and I have much to learn!  But once you start noticing tracks, you'll probably find more than you might expect!  Keeping my eyes open for mammals tracks and other signs always adds a great deal to any nature walk.  From bear fur to otter scat to a squirrel skull, you never know what you might discover in nature!

To learn more about identifying mammals tracks and other signs, I recommend the book Mammal Tracks and Sign: A Guide to North American Species, by Mark Elbroch.  
I also have an old battered copy of Field Guide to Tracks of North American Wildlife, by Myron and Charles Chase that I really love and have used quite a lot!

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About Me

Named after the Sierra Nevada Mountains, I am a naturalist and avid birder based in Central California. Above all, I am a follower of Jesus Christ, our amazingly good Creator God whose magnificent creation is an unending source of awe and inspiration for me. I hope to inspire others to appreciate, respect and protect this beautiful earth we share, and invite you to come along with me as I explore the nature of California and beyond!
- Siera Nystrom -



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