Porcupine

Saturday night while heading to our camping spot at Frenchmen's Coulee we heard shifting rocks in front of us. In the half-moon light, after a couple of minutes watching and listening, I was able to make out the shape of ... a porcupine? It was hard to be certain: when I looked directly at it its shape disappeared - I could only see it in my peripheral vision. When it had been quite for several minutes, we investigated with a flashlight and were able to confirm a smallish porcupine, now huddled behind a small boulder.

In the morning we spent a few hours exploring in the morning light. We each went back to investigate the spot of the sighting, though I did not see too much evidence of its passing. I thought it may have come down from the edge of the adjacent cliff band, so up the scree I climbed. There was certainly porcupine sign there - under overhangs, behind masses of vine brambles and out in the open - but no obvious sign of regular habitation. Shawn explored further down the canyon though and found a couple of porcupine sized holes overflowing with scat.


On our way back out, in almost the exact same spot we again encountered the porcupine again. I guess he had the bad luck to be heading out and back in at the opposite times as we did.

Track of the Week 2

The response to last week's track of the week was better than I expected. It was great getting so much advanced participation in the comments. My initial plan for this was to aim it at a more beginner to intermediate level though and I'm not really prepared (or knowledgeable enough) to target it at folks interested in studying pressure releases. I hope that such people stick around though and are able to stretch themselves with the pictures I am able to offer anyway (and perhaps as time goes on I will begin to gather more pictures that will be increasingly useful for such study).

That said, I would like to request that if you are a more experienced tracker you leave the answering of the official questions to the newer trackers, at least for the first couple of days after I post them. The way I envision things, perhaps you could discuss the more advanced topics without mentioning the answers to the more basic questions. After a couple of days go by though, please feel free to answer those questions as well.

People who are newer to tracking, please feel free to post comments even if some of the other comments are over your head (some of them have been over my head too!) I hope that people at all levels of tracking skill feel welcome to post their analysis and feel free to ask questions too!

This week's mystery:
This picture was taken in central Washington.



Questions:
1. What is the species at the top?

The top species is a porcupine. As some of the comments mentioned, the overall shape and pebbly texture in the tracks are characteristic of this species as are the quill drag (though I've seen trails where it is much more noticeable) and the long claws. The claws here don't show up very distinctly, but at the front of each of the tracks they make a disturbance a bit to the inside that is more or less perpendicular to the direction of travel.

Porcupines are pretty interesting in that they have long claws on their front and hind feet. I can't think of any other animals quite like that, and all other animals with particularly long claws that come to mind are diggers and as far as I know the North American porcupine doesn't do much digging. I read that African porcupines will dig for roots though. I've seen a number of websites that claim that the long claws are useful for climbing trees which porcupines do a lot of, but that doesn't seem to line up too much with the fact that of the animals that I can think of that have particularly long claws and the animals that climb trees a lot the intersection is only the porcupine. I've read that their textured feet are also useful for gripping trees (makes me think of those rubber grippy pads for opening jars).

These tracks are near the top of the size range that Elbroch gives in Mammal Tracks & Sign for porcupine. Apparently porcupine are sexually dimorphic with males being larger, but I was unable to find anything saying how much larger they tend to be. But given the size I wouldn't be surprised if it was a male.

2. What is the species at the bottom?

I believe this is a coyote trail. The size range on the individual tracks could work for a red fox or a coyote, but I think fits the coyote better. I believe it is in an overstep walking gait (I will discuss why below) in which case the stride fits much better with a coyote. I've also seen tons of coyote in this area and while I wouldn't rule out the possibility of foxes being around, they don't seem to be nearly as common there.

Based on the size of the tracks, from left to right we have left hind, right front, right hind. In canines the front foot shows up bigger then the hind. The right hind is a little tricky because it appears bigger than the left hind, but compared with the middle track (the right front) the heel pad seems smaller and the overall track seems a bit narrower. With that placement of feet the gait could be an overstep walk, overstep trot or a lope. I think the disturbance in the tracks is pretty low for it to be a lope or a trot, so I think a walk makes more sense there. Additionally an overstep trot like that is pretty rare, where as overstep walks are common.

3. Who came through first?

As was mentioned in the comments, in the left edge of the picture the coyote and porcupine tracks are quite close. It is hard to tell for sure if the coyote track is disturbing any of the porcupine tracks, but it would be hard to believe that the coyote track would remain so undisturbed if the porcupine had walked over it that closely. I would feel somewhat hesitant to say for certain based on that, but I have a picture from later on in the trails that confirms that the coyote came later.

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