Kathy -- when I went back out, I decided that BOTH nests look like they are primarily twigs, though there certainly are some more grass-like pieces as well as a few small seedheads (maybe dried sedum?) in the second one (it's also not as deep). I pulled out the one that was clearly all twigs (had a very deep "cup" in the middle but no eggs), but I left the other because I just wasn't sure. Here are the two pictures: first is the all-twig one that I removed today (how well do I need to clean out the box? I think there are a few twigs on the floor since I didn't have a brush with me). The second is the other box. Just a note: these two boxes are fairly close together because last year we had tree swallows and I had read that tree swallows and bluebirds will "share" space if there are two boxes. Swallows won't let another swallow pair nest nearby but will leave the bluebirds if they want the other house. I think what I read (on Audubon site or somewhere) was to put the two boxes about 10-15 feet apart. I know that's not what you do if you want actual bluebirds to use them both, but we were hoping to keep a pair of bluebirds in the one if the swallows returned this year (those swallows are GORGEOUS birds, too!)

Sounds like you really have some challenges. You have my sympathies! A tiny poked hole is more likely a house wren's thin sharp beak, sometimes taking them some distance away, or simply tossing them out. The house sparrow will toss the eggs out, but their finch-like beak would not as likely make a tiny poke hole. And the HOSP is more likely to stick around, harass, or even take over the cavity. "Do BB's destroy their own eggs" ... No "the nest possibly could have been flooded?" ... are there leaks that could be fixed? "Are the HOSP really sneaky" ... yes, but HOWR are sneakier ... "and resistant to the Sparrow Spooker?" ... yes, and house wrens will not be deterred by a sparrow spooker. House Wrens are even sneakier, faster and silent, leaving no evidence behind, only destroying eggs or young. You might hear them singing, but might never, ever see them! There are some links to sound files of house wren song and chatter on Bet's web pages, so you can learn to hear the unwelcome sounds of house wrens. Visit Bet's web page for more info. And by the way, the Carolina Wren is a very different bird, welcome almost anywhere; not a threat to other birds. BlueBars Here is a link that might be useful: http://www.sialis.org/index.html

As lisa likes to say....I don't think any bird police are going to be coming by your place if you remove that egg and nest. That is what I would do...but that is up to you. If you let them nest then there will be approx 7 more wrens to deal with next year....

Oh my, what a quandary! Our bluebirds have been battling HOWR too. But they have defended their territory and protected their 4 eggs. So far so good. The wren was removing nest material before the bluebird eggs were laid, so there was only a minimal amount of pine needles left in there. All the soft grasses had been removed by the #$@% wren. So the bluebird eggs are being incubated, but are nearly touching the wood floor. I've wondered if I should add some soft grasses, but then, I think, Mama knows best. Sometimes it is difficult to know what to do. Surely a wren guard would not help you at this point. Sorry, I'm no help at all. BlueBars