Clean out and moving two boxes out of marshy ground

I went out there with a shovel again, and as I had 14 boxes to check as well, took the bike, the shovel is on it:

that is a small loop that has no bike traffic. I moved the two boxes back there, as they had been in wet ground for years and tended to tip over. One box is in slight upland near the creek now, with the other one almost by the creek:

I cleaned out all 14 boxes, but there was a slight problem in that three boxes were occupied by field mice. How do I know? I had seen that once or twice before and the mice had left by end of May. This however had a mouse, because the mom jumped out as soon as I opened the box. She will climb back for her babies. They can even move the babies one by one, if she thinks I am a threat. The fluffy cotton will come up all the way to the hole.

I found two house wren nests left from last August. They make a tiny nest on top of the sticks the male puts in:

There were 5 or 6 bluebirds acting aggressive to each other as they sort out the nesting issues, territories. Also some tree swallows were beginning to look at boxes. They claim them but do nothing till one day in May, a nest is all built, feather lined and eggs appear almost immediately.

Bit of video: