I was so relieved when the Bluebird pair survived our 3ft snowstorm. And I was delighted when they started building a nest in one of the boxes.
Then the Tree Swallows arrived, and they tried to claim that nest box, but the Bluebirds persisted, and claimed it as theirs. For over a week I saw only the Bluebirds around that box.
Then I checked it and found this:
Dammit, when did the Tree Swallows sneak into the nest!
And Monday:
I was beyond disappointed. Tree Swallows are cool, but I want Bluebirds!
But then Wednesday, when I stepped out of the back door to open up my little greenhouse for the day, a Bluebird flew out of the box! I checked, and sure enough, still 5 little pink eggs! Is the Bluebird sitting on the Tree Swallow eggs?! WTF!?!
Beyond baffled I emailed the story and pictures to a couple folks who know way more about Tree Swallows and Bluebirds than I do. The response: Its still WAY too early for Tree Swallows to be laying eggs at my latitude, and despite the color those eggs are shaped like Bluebird eggs! I was vaguely aware that sometimes Bluebirds will lay eggs so pale as to look white, but not that they can be so pale as to look pink! But it is a known phenomenon!
I’ll be looking to add powdered calcium to the live mealworms I feed, and I’ve contacted the local Bluebird society to see if there’s anyone who’s interested in banding the female for study.
The things you learn!
I thought for sure that blue bird eggs were always blue. Not because I know anything about them, but all the folklore says they are blue. Learn something new every day!
I’ve never seen anything but blue, though one set one year was really really pale blue, almost white. Pink? I had no idea till this!