Determining Direction of Travel on a Fisher Trail
“Which way them critters goin’?” my friend Dani would call out every time I mentioned I was leaving the house to go tracking, and to this day it can be really tricky, especially in deep snow. For me it takes a good amount of analysis from the moment we encounter a trail, and all throughout as many animals will backtrack, circle round, walk on older trails, walk in another animals trail, or even in their own older trails. There are many points when trailing an animal that the direction of travel can be confused or undetectable entirely. But instead of giving up, we have processes that can help us, especially when they are used in combination over longer stretches of the trail.
For this exploration in determining the direction of travel (DOT), I’ll use a snowed in Fisher (Pekania pennanti) trail we encountered during an Earth Tracks Tracking Apprenticeship outing at Bognor Marsh, near Meaford, Ontario as an example. It was a faint trail, mostly snowed in, but the impressions were visible at the right angles, as long as they hadn’t been blown away in the wind.
Shape and angle of the impression
Rounded solid edge would indicate the direction of travel (DOT).
It is certainly hard to see in the photos, and believe me when I write that it was also hard to see in person. At some spots these tracks were invisible to see entirely, and some you had to look at the trail in just the right angles to see the faint snowed in trail. But we took the time as we wanted to fore track the Fisher, to follow them in the direction they were going in, rather than back track and go in the direction which they had been coming from.
When we first came up to the Fisher trail we quickly examined the faint impressions to look for the shape of the impressions. I wanted to see if there was a broader rounded edge and a narrower tapering edge of each track. The broader, more solid edge of the track would be where the toes are, and this edge tends to be deeper than the heel or back of the track, as I have noticed that most wild animals tend to be a bit more “toe heavy” and their feet sink in at the front a bit more. The heels however do not always register in the track as deeply and tend to taper in appearance and depth. So in the photograph above and the poorly drawn image on the right would both indicate that the Fisher’s DOT is towards the top of the screen.
Look for the toes
Even though we didn’t find any clear tracks on this particular trail, looking for impressions of the toes at the front of the track is very useful technique for discerning the DOT. Deep incisions into deep snow are often angled in such a way that we can’t see the track floor where the actual imprint sits. We can still use this track to determine the DOT by digging away a few layers of snow, or taking off our gloves and using our bare hands to feel the track. By doing this you can sometimes feel the number of toes, or the ridges between the toes like the cleave between toes 3 and 4 of a deer.
Behaviour like turns and stops + Look for the track pattern
As we carried on the Fisher trail we encountered a couple of times where the Fisher slowed down and investigated. We couldn’t tell what the Fisher was concerned with but we could tell that they slowed and turned. One way we could tell this was by looking at the track pattern left in the snow. In the photo above, the Fisher slowed to a walking gait as they made their way up from the bottom right of the image. Then their trail arced back towards the bottom left of the photo before quickly continuing on their trail in a loping gait towards the top of the image, leaving behind quicker 3x4 and 4x4 track patterns.
We can look at the track patterns and consider the movements of the animal by comparing with what we know about Mustelids (the Weasel family to which Fishers belong) and by thinking of ourselves. Weasels and humans tend to slow down when when investigating something. We will walk to look carefully, and only when we are ready to move on will we jump back into high gear and take off again. This change of gait, from a slow exploratory walk to a faster 3x4 loping gait used by Fishers to cover ground, can be seen as an additional tell of the DOT in the trail. So once we see the DOT we can recognize that the track patterns left behind indicate that the animal moving from the bottom of the image, across and arcing to the left, then up the image and out of the frame.
If we were to imagine the Fisher or ourselves coming from the opposite direction, from the top of the image down towards the bottom, we could see that the animal is moving quickly because of the track pattern indicating a faster gait. They then stop suddenly, without an apparent disturbance to the snow, leaving no slide from slipping, no thrown debris from the forward momentum. The trail would then have to be interpreted as the Fisher walking steadily backwards in an arcing trail until out of the frame on the lower right. While I have seen a Mink (Neogale vison) walking backwards to avoid being noticed, this behaviour is pretty rare and unlikely. Instead we have to assume the more likely storyline, while putting the pieces together in a logical way, noting the behaviour of the Fisher. If we do this we can see that their DOT was towards the top of the image.
Pointing with feet
Pointing with feet implies the times when an animal is looking in a specific direction, perhaps to see what is going on, or to listen, or perhaps even to browse on some nearby shrub. The animal will put out a front foot in the direction that they are looking. The track may be very lightly impressed in the snow. The track will appear out of baseline, out of the regular rhythm of the regular track pattern left behind, indicating that something happened here and it is worth checking out. This is also a moment to determine the DOT because the front foot, either left or right, will be facing forwards towards the DOT but perhaps slightly to the side.
I see this a lot with ungulates such as White-tailed Deer (Odocoileus virginanus) and Moose (Alces alces), but have also see this with Lynx (Lynx canadensis) and Coyotes (Canis latrans). I realized I didn’t get any photos of this behaviour, but it could be lumped with the heading above.
Debris
As mentioned above, another good way to determine DOT is to look for debris in the trail, especially snow kicked up at the front of a track. I was discussing this characteristic with a student this Winter who was quick to demonstrate that snow will be pushed out of a track to their rear, pushed behind them as they lift their foot as result of forward propulsion. They then replicated this by sticking their boot into the snow in a mock step and then intentionally dragging snow out behind them. My response was to point something out ahead of them, something too small to see from where they were standing. They had to walk over to the fictional point of interest, now distracted from the point they were trying to make. When they have walked over to take a look, distracted from the point they had just made, I got them to stop, turn around and look at their trail. Most of the snow had piled at the front of their tracks where they lifted their boots out of the snow. This was pretty convincing.
Now, snow or other substrates can be thrown back behind a track when an animal, including humans, are moving at a faster pace, pushing off of the ground with a forceful step, but I only remember seeing this when someone is starting to move in a run. When I think of it now, it makes me want to go out and try some experiments with a tracking class and see what we can figure out. Will more snow be thrown backwards as more force is being used to propel a body forward?
“When in doubt, track it out”
Once, we were on a Red Fox (Vulpes vulpes) trail for four hours before seeing a sign of the DOT. The snow was too deep to see toes in the tracks, and when we reached in, we still couldn’t make it out. We followed the trail for the morning and then stopped for lunch. It was only after lunch that we encountered a stretch of the trail where the fox had jumped over a log, knocking over some snow which had piled up on the log, that we were able to tell which way the fox was going. We looked to the snow to tell which way it had been knocked over to determine the DOT.
I share this story because sometimes it’s truly difficult to figure out the direction of travel. I have been challenged over and over, humbled so many times by different animals moving through varied substrates at multiple angles of slope. It really comes down to taking our time to sort it out with each new trail we encounter. We can use the tools described above, and likely many more I don’t know about yet, but this takes time in the field and patience with the trail.
“When in doubt, track it out.” Persist in the journey. Focus on the baseline and any changes in the track patterns which may indicate behaviours, and then feel out those behaviours to see if it feels like it would fit the mechanics of the animals body. Look for the deepest part of the track and for debris kicked up at the front of the track. And if you still can’t sort it out, keep going.
To learn more :
Mammal Tracks and Sign by Mark Elbroch and Casey McFarland. Stackpole Books, 2019.
When the Snow Gets Deep - blog post by Linda J. Spielman