While clearing out brush and a large pile of scrap wood and old aluminum siding, I found a pair of these mice. They were identified by their large size, long, indistinctly bicolored tail, and their darker upperparts and pale belly and feet.
As the rat wasn't very interested in the trap yesterday, I added a bit of meat as bait. It certainly showed a lot of interest, but couldn't find the entrance! I suppose I need a little light over the entrance with a label in rattish.
It spent a whole second paused looking at the wall, not sure what the interest was.