Right at dark last night, I noticed a lone martin circling my housing and trying to land on perch rods that I had removed for the winter. Right at dark, I thought I saw this martin land on one of the tunneled entrances which I do not remove for the winter. This morning at 6:15, I noticed something sticking out of one of the tunneled entrances. Here is picture of what I saw.

After the flash from the camera went off a couple of times, I got a picture of the martin as it existed the tunnel and flew off.

This martin felt secure enough to spend the night in the tunnel of the nest without a door. Needless to say, I will be putting a few doors back on this house today in case it, or others, decide to return for another night or two.
