Hm...too bad that you to have to loose some!
I was reading ones,.. sometimes those blocks are taken down and stored somewhere for a while after they are filled.
Konrad

My latest education concerning bees and birds was last summer, when I began to notice a few of the larger species of birds hovering around the bee hives. They were sitting on the fence waiting for a bee to return to the hive with pollen or nectar, and then swoop down to catch dinner.

I didn't think too much about it, except that one over-zealous guard topk exception when the alarm sounded, and it chased not only the blue jay but me all of the way to the back door. I managed to get inside - and left the jay to fend for itself. After all, I figured it was his fault, not mine and so I left him sitting on the railing outside the kitchen door.

The only thing - is that for several weeks, every time I happened to be near the hive, I was attacked. Soooo - I finally took a can of Raid, and did what any red-blooded, property protector would do - I zapped it.

Just my 2 c's.

Bejay

I read that the nesting bees lay the female eggs first, in the back of the tube, and when predators raid the tubes, they are more likely to eat the males in front, leaving more females to survive and reproduce. Someone told me that the woodpecker beak can't get to the end of longer holes.