A couple months ago a mysterious little hole appeared in the middle of the towpath of the Delaware and Raritan Canal, where I ride twice every day.

I go by there just before it gets light in the morning, and just after it gets dark; and I usually see the hole just in time to avoid it. It's not a big hole, just a few inches deep, but one time I didn't see it and found that it was pretty unpleasant to hit it with my 16" wheels. So I stopped and filled it in. Next day, the hole was back! I filled it in again. Next day, the hole was back, and a little deeper. I filled it in again. This kept happening. Part of the problem was that I only saw the hole by the light of my generator light, which goes dark when I stop.

Finally, a couple weeks ago, I examined the hole by the light of my cell phone, and saw distinctive little scratching marks that suggested it was being dug by a squirrel. I guess the little varmint smelled the freshly moved soil, figured somebody's buried a snack, and dug it up. So I filled it again, and peed on it this time. And (knock on wood) that seems to have taken care of the problem. So now I've filled in another hole the same way, and with good results so far.

Stupid squirrel.