He does quite a little work in the night, but he is only, say about, an inch long so it's not much in the big picture. The most I have seen him do are the tunnel like entrances around the base of two adjacent rocks that he lives under. So there will be tunnels coming out of a few places, then a few days later those are all mounded over and there are a few new tunnels out from under the same rocks.
Last night he mounded over the opening that the watchman has always used to go in and out of his little rocky cave, the watchman got out from some other spot and then went around to the front and used his tail to swish away and open up his entrance again.
The funniest part was the little pistol pinching at the watchman's tail and fins as he tried to grab for food and the watchman didnt bat an eyelash, if anyone else even looks twice at the watchman he beelines it for his cave. So they must be buddies.