Bluebirds blog and other nesting activity in Nebraska

I am still doing the boxes this year. My daughter gave me 4 boxes to put up (to replace the worst 4) as a Christmas present. The park has some boxes that I can use, made by a volunteer, but are way too big. House wrens will take over those as well, but it is a lot of empty space the male has to take up with ticks before the female makes a tiny nest.

I put some cardboard on one occupied nest to keep the wrens out. They break the eggs.
pioneersparkbluebirds.blogspot.com/2019/07/on-your-own-for-next-10-days-and-some.html