what is that in my bluebird box
Yesterday, I took a little hike down ASP Rt. 2 looking for some Shrikes or any other unique winter bird hiding in the shrubs. Being so quiet, I found myself looking inside some of my bluebird boxes that I have not checked since August (removing the older nest left by the bluebirds).
One of the boxes had been filled up with grass. Anyone who has worked with nest boxes knows that I am about to deal with some little furry mammal (not birds). Sure enough, there were 2 Deer Mouse holding their ground and not wanting to leave the box. I was just glad they didn’t run down my arm like they normally do when I open the box.
I questioned if I should have left these mice alone or just evict them. If this box was regularly used by Tree Swallow’s, I probably would have let them spend the winter there but this exact box has been one of my better Eastern Bluebirds boxes for the past 5 spring/summers. I am afraid that these mice might discourage any bluebird looking for a winter roost or for when the birds decided to start investigating for an empty box. I am also concerned that the urine left by the mice could attract predators which might destroy the box trying to get inside (This summer I had a Black Bear shred apart a box to get inside, ugg). Anytime you remove a mouse nest, you should always use protection over your face so that you don’t inhale any of their dandruff. You should also try leaving the box open for a week to dry the soaked mice urine left buy these cute furballs.
Last spring I encountered this Red Squirrel in one of the new boxes built by some Boy Scouts. It is hard to believe that something so big can live in such a little box. I have found that these squirrels do all kinds of damage by chewing the hole bigger which can then make it easier for predators (raccoons, ect..) to steal the baby nestlings or eggs from the box.
It can become a full time job taking care of all your bluebird boxes but very well worth seeing and hearing the birds out in the fields. I promise to keep you updated with this blog on how the boxes are doing here in Allegany State Park.