[birdky] bluebird nestbox - maybe I'm not so smart

I've mounted bluebird nestboxes on the metal T-posts of an interior fence.
Below each nestbox, attached to the post by insulators, are three strands of
electrified high tensile.  I thought this was a pretty good approach -
seemed unlikely that a raccoon or possum could climb the post without
contacting a hot wire.

 

 Today I noticed that remains of a tree swallow egg on the face of a nestbox
below the opening.  Two eggs remained in the nest.  This particular box has
a wooden collar around the opening, I presume to defer a predator from
reaching into the box.  

 

Could a hawk or owl have robbed the nest?  Maybe a small bird attempted to
leave the box with an egg.  

 

Mike Tobbe

Little Mount 

Spencer County

Other related posts: