I also wonder what I should do with the broken eggs on the ground, and what (if anything) I should do with the bluebird nest?

very carefully (with a wide spatula or putty knife) remove the nest from the box, put it in a little paper bag of some sort (plastic will draw moisture which isn't good) and store it somewhere dry. sometime in the future, it may come in handy if an active nest is plagued with ants or mites, etc.

as for preventing wren activity, it's pretty much a lost cause (at least in my own experience) once a wren has found the nest box. you may be able to move the box to a different location where you have not yet seen or heard wrens. if the blues nest again, immediately after the first egg is laid, slap a wren guard up and you might have a better chance of a successful nesting.

i am holding my breath...i have 4 eggs due to hatch next wednesday, my female absolutely refuses to accept a wren guard and i'm hearing wrens all over the place. ugh!

So I should not leave the nest there? I thought that females start another nest immediately if one is destroyed (although I could be wrong). Better to take the nest out so that another species can nest (we've had lots of tree swallow activity lately) or leave it there in hopes for another bluebird brood?

I spent all afternoon reading about wren guards and will definitely use one next time we have blues.

Here's to hoping your own eggs hatch next Wednesday!

Any clarification about the nest would be appreciated.

LadyJemima, that happened to my eggs also. Female never incubated them. I guess a wren got them and pecked holes in them. Nothing but liquid, not viable. I removed the nest and some tree swallows have been around. Have four eggs in another box. I pray a wren doesn't get them too.

you should remove the nest. the female bluebird may build a new nest in the same box. however, if she feels threatened by the wren (which she may very well feel), she will look for a different place to nest.

wren guards are usually only effective if placed BEFORE a wren finds the entrance hole. once they have, they will go right under a wren guard.

So will that particular wren remember that the hole is there, even if next time I put up a guard? I mean, there's a chance he/she won't come back, right?

My female was not around at all before the wren got the eggs. She and the male had not been seen for over a week before the eggs were destroyed.. Something must have happened to her. I did take my nest out. Swallows have been around. We will see.

LadyJemima, unfortunately for us bluebirders, wrens are tenacious little birds and yes, they will remember the hole is there.

i am hoping my nesting will be successful this time. last year, i lost every single nesting (3 different nest boxes) to wrens. i finally just put a van ert trap in the boxes and sprung the trap so nothing could get in. i saw no point in letting the bluebirds nest when i already knew the wrens were gonna destroy the eggs.