This female bluebird stayed on the wire near her nestbox as we checked it late this afternoon. She has four nestlings about a week old in this nestbox in rural Rice County -- the second brood of bluebirds in this box this year. We were there on hatch day last week, finding three tiny nestlings and one egg not yet hatched. This is one of only three locations this year where bluebirds have started a second brood, and we have quite a few empty boxes right now. Last year quite a few of them managed two broods. It's been a tough year for bluebird survival and reproduction.
This year so far 21 bluebirds have fledged out of six nestboxes, with a potential of 12 more to come in the three second-round nests, if they all survive. Tree swallows have raised broods in several of the other boxes. We took on three new nextboxes just a couple of weeks ago, which showed evidence that one brood of bluebirds and two of tree swallows had been raised there, but we don't know how many, or whether they were definitely from this year or not. Chickadees started nests in two more of our nestboxes, but, sadly, neither of them successfully raised a brood -- in one, the eggs were abandoned before hatching, and in the other the nestlings disappeared from the nextbox before they reached fledging age. We have house wren eggs in one box right now.
In the next 10 days to two weeks, in all likelihood, the bluebird breeding season will be over for this year.