Young black bear inspects my camera trap
Black bears (Ursus americanus) are a widespread species across North America, their range often overlapping with that of grizzly bears (Ursus arctos) in certain regions. While observing these magnificent creatures in their natural habitat is a privilege, especially in national parks where they are accustomed to human presence, encounters outside these protected areas are less frequent. In the wilder landscapes, you’re far more likely to come across the telltale signs of their passage: their tracks. However, distinguishing between grizzly and Black Bear Paw Prints can be challenging, a puzzle that even seasoned trackers sometimes find perplexing. The key to accurate identification lies in a comprehensive approach, examining multiple features across several tracks, rather than relying on a single characteristic.
Grizzly vs Black Bear Tracks: Beyond a Single Glance
My experience in the field has taught me a valuable lesson: resist the temptation to jump to conclusions based on a single track feature. Factors such as the type of ground surface (substrate), the age of the tracks, and even individual variations in a bear’s foot anatomy can significantly alter the appearance of a paw print. What might seem like a definitive characteristic in one track could be misleading in another. Even within the same trail, subtle shifts in the substrate can lead to inconsistencies in the tracks left by the same animal. Therefore, a methodical and multi-faceted approach is crucial when attempting to differentiate between grizzly and black bear paw prints.
Mystery Bear Tracks: A Case Study in Montana
Recently, while exploring the Montana wilderness, I stumbled upon a fascinating trail of bear tracks imprinted in the wet snow. These “mystery bear tracks,” as I began to call them, exhibited an “overstep walk” pattern. This pattern, where the hind foot lands ahead of the front foot track, is ideal for track analysis because it prevents the hind and front tracks from overlapping and obscuring each other. This clear separation provides an excellent opportunity to meticulously examine both front and hind paw prints.
grizzly vs black bear tracks, these are grizzly
I selected three sets of exceptionally clear front and hind tracks from this trail and proceeded to take precise measurements. Based on a careful analysis of several features, I initially leaned towards identifying them as grizzly bear tracks with a reasonable degree of confidence. However, an online discussion about these tracks brought forth differing opinions, prompting me to re-examine them with even greater scrutiny, much like the curious young bear inspecting the camera trap in the opening image. While I still believe grizzly is the more probable identification, I remain open to alternative interpretations and encourage readers to share their insights.
Known Black Bear Tracks: A Comparative Example
To provide a clear point of comparison, I am including photographs of known black bear tracks. These tracks were captured by wildlife photographer Randy Robbins (explore his stunning work at Randy Robbins Photography). Crucially, Randy witnessed the black bear making these tracks, eliminating any ambiguity about their origin. These black bear paw prints, also imprinted in wet snow and exhibiting a dark appearance, serve as an excellent visual benchmark against the mystery tracks I discovered.
black bear tracks
Key Features for Distinguishing Bear Paw Prints
In my analysis of the mystery bear tracks, I focused on four primary distinguishing features: claw length, the 5th toe / interdigital pad rule, the amount of negative space within the track, and overall track size. I then compared these features to those observed in Randy Robbins’ known black bear tracks. For a visual guide, refer to the labeled graphics added to the photos at the end of this article, which highlight these specific features. Let’s delve into each of these characteristics in detail.
1. Claw Length: Examining the Front Paw Claws
Grizzly bears typically possess longer and straighter claws on their front paws compared to black bears. This difference is directly related to their foraging habits, as grizzly bears utilize their long claws for digging and excavating roots (as discussed in Grizzly Bear Root Grubbing). Some trackers consider claw length to be a primary indicator, employing rules of thumb to aid in identification. For instance, tracker Paul Rezendes suggests comparing the claw length of the middle toe on the front track to the toe’s length itself. If the claw mark is longer than the toe length, it’s more likely a grizzly bear paw print. Conversely, if the claw mark is shorter, it’s more likely a black bear paw print.
However, it’s crucial to acknowledge the limitations of relying solely on claw length. Rezendes himself cautions that in approximately 18% of Alaskan brown bear tracks he examined, the claws were surprisingly shorter than the toe length. Similarly, bear tracking experts Mark Elbroch and Casey McFarland emphasize that claw length alone is not a foolproof distinguishing characteristic. Once again, the consensus underscores the importance of considering multiple features for accurate bear paw print identification.
In my mystery bear tracks, the claw marks of the middle toe on all three front tracks are clearly visible and noticeably longer than the corresponding toes. (Refer to the photos with graphics for visual confirmation). This observation aligns with the characteristic claw length typically associated with grizzly bear paw prints. I was unable to definitively discern claw marks in Randy’s black bear tracks, so they are not labeled in the accompanying images.
2. The 5th Toe / Interdigital Pad Rule: Analyzing Toe Arc on Front Paw Prints
This technique focuses on evaluating the arc formed by the toes on the front paw print. It’s specifically applicable to front tracks and less reliable when analyzing tracks in direct register patterns where the hind foot obscures the front track.
Grizzly bear front toes tend to be arranged in a shallower arc, sometimes approaching a nearly straight line. In contrast, black bear front toes exhibit a more pronounced, curved arc. To assess this arc, visualize or draw a line extending from the proximal edge of the outermost toe (toe #5) to the distal edge of the fused interdigital pad (the large pad analogous to the palm of a human hand). This line is depicted in green in the track photos accompanying this article.
When analyzing tracks in soft substrates, carefully determine the true edges of the outermost toe and interdigital pads. Refer to the “minimum outline” concept, which defines the outline at the base of the track, as explained in detail here.
Interpret the results as follows:
- If more than half of the innermost toe (toe #1) extends beyond the line, the track is likely from a grizzly bear.
- If the line bisects the toe, the result is inconclusive, requiring examination of other features.
- If more than half of the innermost toe falls behind the line, the track is likely from a black bear.
For optimal accuracy, apply this rule to multiple front tracks from the same animal, particularly if the innermost toe doesn’t clearly fall definitively beyond or behind the line. In all three front mystery bear tracks, more than half of the innermost toe falls beyond the green line. However, because none of the toes are entirely beyond the line, it’s reasonable to consider the evidence as leaning slightly towards grizzly, but not unequivocally conclusive, leaving room for interpretation.
black bear track at left, grizzly track on the right
3. Negative Space: Examining Fur and Pad Impressions
Grizzly bears tend to have less fur on the soles of their feet compared to black bears. This difference in fur density impacts the “negative space” observed within their paw prints. Grizzly bear tracks often exhibit less negative space, with toes appearing closer together and minimal negative space between the interdigital pad and the heel pad. However, a crease between these two pads may or may not be visible in the track.
Black bears, with their denser fur between the toes and a distinctive wedge of fur in the “arch” between the interdigital and heel pads, typically leave tracks with more negative space. In ideal substrates, this fur wedge is likely to appear as a distinct negative space within the track. However, in certain substrates, this wedge may not be clearly discernible. While two of the hind tracks in my mystery track example show no clear evidence of this wedge, one track presents an ambiguous impression. There appears to be a wedge-like feature, but it’s uncertain whether it’s genuine negative space or an artifact of substrate irregularity (refer to the photos and descriptions at the end of this article for closer examination).
Elbroch and McFarland consider negative space to be a reliable distinguishing characteristic. However, given the influence of substrate on the visibility of negative space, it’s prudent to avoid relying solely on this feature for bear paw print identification.
4. Track Size: Considering Hind Paw Print Length
While there’s considerable overlap in the track sizes of grizzly and black bears, track size becomes a valuable indicator when a track falls outside the typical size range for one species. In the case of my mystery tracks, the length of the hind paw prints exceeds the reported range for black bear hind tracks in two highly regarded tracking guides.
Elbroch and McFarland report a maximum black bear hind track length of 8 and 7/8 inches, including claw marks. Rezendes cites a slightly smaller maximum of 7 and 3/4 inches for the same measurement, also including claws. The hind track lengths in my mystery photos, measuring 9 and 1/4 and 9 and 1/2 inches, exclude the claws. Therefore, these measurements significantly surpass the reported maximum size for black bear tracks, making them more consistent with the larger size range typically associated with grizzly bear paw prints.
5. Bonus Feature – Track Depth: Observing Front vs. Hind Track Depth
Here’s an additional feature, highlighted by zoologist Vladimir Dinets on social media, that can provide further insights. Due to their powerful shoulder musculature and characteristic shoulder hump, grizzly bears tend to leave front tracks that register more deeply than their hind tracks. This depth differential is not typically observed in black bears, which lack the prominent shoulder hump. In fact, as black bears accumulate weight during periods of hyperphagia (excessive eating in preparation for winter), their hind tracks may become noticeably deeper due to the added weight of their substantial belly.
Unfortunately, I wasn’t aware of the significance of comparing front and hind track depth when I initially discovered my mystery bear tracks, and my photographs don’t readily reveal any discernible difference in depth. However, I will certainly incorporate this feature into my track analysis in future tracking expeditions.
Bear Paw Prints with Graphics for Visual Aid
Mystery Bear Tracks
(Above) Montana mystery bear tracks analyzed. The combination of long front claws, large hind track length, limited negative space in the hind track “arch,” and the shallow toe arc in the front track leads to a likely identification as grizzly bear tracks.
grizzly vs black bear tracks
(Above) A pair of tracks from the same trail, highlighting a potential wedge of negative space in the hind track. However, the wedge’s extension to the distal edge of the interdigital pad raises questions about whether it’s a genuine negative space or an artifact of substrate variation.
(Above) Another pair of tracks from the same trail. In this front track, nearly half of the innermost toe falls behind the green line, which is considered equivocal. An indentation is visible at the “arch,” but it’s less pronounced than the typical negative space wedge seen in black bear tracks.
Known Black Bear Tracks
black bear tracks
So What’s the Diagnosis? Probabilistic Track Identification
When identifying animal tracks, particularly bear paw prints, it’s essential to think in terms of probability rather than absolute certainty. Can I definitively state with 100% assurance that the mystery tracks are from a grizzly bear and not a black bear? No, absolute certainty in track identification is often unattainable. However, when considering all the analyzed track characteristics collectively, they lean more strongly towards a grizzly bear identification than a black bear.
If my Montana tracks were indeed made by a black bear, it would have to be an exceptionally large individual with unusually long claws, a somewhat shallower toe arc, and perhaps less fur on its feet than is typical for its species. While not entirely impossible, this scenario is statistically less probable than the tracks being left by a normal-sized grizzly bear with characteristic claw length and a slightly more pronounced toe arc.
grizzly mother and cub
Sources
Elbroch, M. and C. McFarland. Mammals Tracks & Sign: A Guide to North American Mammals. 2nd Edition. Guilford, CT: Stackpole Books, 2019.
Rezendes, P. Tracking & the Art of Seeing: How to Read Animal Tracks and Sign. 2nd Edition. New York, NT: HarperCollins Publishers, 1999.
What are your thoughts on the most reliable methods for distinguishing between grizzly and black bear paw prints? Share your comments and questions in the section below.
