First, the good news (yes, there is bad to follow).
We have two (maybe three) female bluebirds incubating, and four new bluebird eggs. And, at least two chickadee eggs have hatched.
Now the bad news, two of the nests have been pilfered, all of the eggs which were once in the nests are gone. And I know who did it.
The nest by nest:
I was glad to see a female incubating in the nest box at the Cow Pasture. Last week there was but one egg in the nest. This week the female sat tight on her eggs as I peeked into the box. I didn’t want to spook her needlessly, so I didn’t get a count of the eggs she sat upon. That, will become evident next week.
The nest box next to the Bungee Jump which contained five chickadee eggs last week now has two nestlings. They appear to have just hatched. The others will probably hatch very soon, later in the day or the next day.
Here’s where the story gets dark. Last week, I counted five chickadee eggs in the nest box at the Sailboat Pond. Those five eggs were absent when I opened the nest box door on Tuesday morning (4/21). I wasn’t quit sure who or what had removed the eggs but the evidence soon came clear. I could hear a house wren calling from the nearby brush. House wrens have a reputation for destroying other birds’ nests. They then build their own nests in the same space.
Things got lighter around the corner in the Amphimeadow. Here, another female bluebird refused to budge as I peered into her nest. Again, I’m not sure how many eggs she now sits upon, but there were five eggs in the nest box last week.
The Picnic Dome nest box was not so fortunate. The five eggs that were there last week were missing. Clear evidence inside the nest box points to the culprit being a house wren.
As you know, house wrens will destroy another bird’s nest to build their own in these ready-made homes that we erect for them. They use twigs to build those nests, not grass or moss like the bluebirds and chickadees. Have a close look at the nest below and you will see half a dozen or so twigs. A house wren put them there!
Off to the Butterfly House nest box. Last week a female greeted me at the nest hole as I approached the nest box. There were, however, no eggs in the nest. This week, a female flew from the box as I approached. When I looked inside, there are were four bluebird eggs. I assume she was incubating, but perhaps not.
So, we now have three incubating female bluebirds, one each at the Cow Pasture, Amphimeadow, and Butterfly House (I think). Two nests have been destroyed by house wrens, or wren, the Sailboat Pond nest (chickadees) and the Picnic Dome nest (bluebirds). At the time of the inspections, one nest had two nestlings, with three eggs soon to hatch (if all goes well), at the Bungee nest.
The two nests that were destroyed may yet produce bluebird or chickadee nestlings. The male house wrens typically build nests in several locations at once. They arrive on the home front earlier than the females. It’s the female who makes the decision where to nest. I’ve only seen one wren nest in any of our boxes and that wasn’t successful. They are sometimes reclaimed by the bluebirds and chickadees after the wrens have had their way.