Thursday, October 11, 2012

CyberTracker quiz question #4

In this part of the quarry, the sand was quite soft. There were many
digs (10-20?) in an area of (very) roughly 20 ft x 20 ft. There were no
clear tracks or runs among these holes, but we had also done a lot of
trampling. The holes were not tunnels - they were maybe about 6 inches
deep. We were asked what species made the holes.


  1. Ybbxf yvxr fxhax be fdhveery. V'yy fnl fxhax.

  2. V unir fcrag jnl gbb zhpu gvzr ba guvf bar. Nz svanyyl ehyvat bhg enppbba naq unir qrpvqrq gb tb jvgu fxhax. Abj V'z tbvat gb rng zl oernxsnfg naq fgbc guvaxvat nobhg ubyrf va gur fnaq.

  3. The accepted answer was skunk. Like Susan, I finally settled skunk after spending way too much time thinking about it. A few of the holes had 2 human thumb size depressions near them that looked like indistinct tracks of correct size for skunk, but I couldn't figure out why there weren't any tracks/trails/troughs among the holes where the animal must have been traveling. Nonetheless, they looked just like those conical digs skunk put in lawns while foraging for grubs, so I figured it'd be best to just go with what it looks like, and not over-think it, as I had done with the owl tracks. They were deeper than the holes skunks dig in lawns, but I think that's because they substrate here was so soft.

    As for raccoon vs. skunk: We did not discuss raccoon, but for whatever it's worth, I think a raccoon's throw mound would be bigger/farther, and hole probably bigger. Also I think of the larger raccoon as going for a bigger caloric payoff, like a hornet's nest, or a crayfish burrow. For a sparse population of smaller insects, which is what I think was in this habitat, I think skunk.

  4. Here is a photo of a hole similar to the one posted. Similar story with several holes existing in the same area. Also about the same size, but this hole was definitely made by a raccoon.

    I believe I have better photos of these raccoon holes, but do not have access to them at this moment.

  5. Then maybe the only reason our examiner was so sure of skunk were the 2 little human sized thumb print like depressions at the base of some of the holes, at the beginning of the throw mound, which I mentioned above. These were about the right size to be indistinct skunk tracks but too small to be raccoon tracks. I believe in my photo, those were present, but some sand had fallen into them, so you cannot see them well.

    So if all you had to go on is my photo, then perhaps raccoon cannot be ruled out, and maybe everything I said about throw mound and caloric reward was garbage. For your photo, I would have said raccoon, too, because there appear to be raccoon tracks associated with the hole.

    I will also add that there were a few times during the evaluation when I felt it wasn't quite fair to rule out certain species and be so absolutely certain of another. And while I learned from the experience, there was too much focus on "the right answer" rather than the thought process, for my taste.

    So for example, in this case, if someone answered raccoon because they'd seen similar digs by raccoon and just didn't notice those thumb sized depressions, and someone else answered armadillo, because they were completely clueless and didn't know armadillos don't live New Hampshire, both participants would get the same score on that question: zero. At least that's my understanding of the scoring system. I found this frustrating, but that's the way it goes.