Birdhouse

I made bluebird houses about 15 or 20 years ago and put them out here. I'd followed plans that included snake and racoon excluding baffles on the poles. In spite of all that preparation, there were some tragic happenings - like house sparrows pecking bluebirds to death on their nests. So, I'd just about given up on them. Most of them have fallen into disrepair, but this one is still whole and had a deer mouse nesting in it a few months back when I peeked in. That's what I was expecting to find, when I peeked in yesterday, but instead there was a nest and five small blue eggs. I didn't see any parent birds anywhere around, and can't remember offhand... could these actually be bluebird eggs???

Funny thing is that whatever bird it is, they've lined the nest with hairs from the deer carcass that was over in the other bamboo clump (Phyllostachys angusta I think).