Bluebird and ? egg in nest

[fishlkmich]

More disturbing cowbird information:

http://elibrary.unm.edu/sora/JFO/v070n01/p0055-p0057.pdf

http://www.sciencedaily.com/releases/2007/03/070305202649.htm

[linrose]

Yikes! Mafia and farming behavior in cowbirds. Dastardly devils! 56% of nests ransacked if cowbird eggs were removed (payback is a *****!) and 20% even if the cowbird never parasitized the nest? (at least in the case of this study with warblers) I'm liking these birds less and less.

[TheLorax]

Thanks for the clarification on when to place sparrow spookers. I think it's too late for the first box, but not too late for this new one.

It is never too late to add a sparrow spooker if English house sparrows are in the neighborhood-
Sparrow Spookers

Sent: Sunday, April 16, 2006 1:52 PM
Subject: RE: spooker

I too saw a male pulling on the mylar right after installation. He actually yanked a few strands off. Pretty soon he was perching on it. Even so, I figured better to have him worried about the mylar than worried about whether a house sparrow was going to peck his head off.
I have yet to hear of a case where a sparrow spooker was NOT accepted by bluebirds after egg laying commenced. Sometimes it helps to put it up when it's not too windy.
Bet from CT
Sparrow Spooker designs and instructions

This man provides directions for making our own sparrow spookers-
Sparrowtraps.net
We do not need for sparrow spookers to be this elaborate for them to be effective. A simple dowel with strips of plastic baggies taped to the back of a nest box is equally effective deterring house sparrows.

[Equilibrium]

Sparrow spookers aren't a big deal. You can buy a pack of streamers that go on kids' tricycle handlebars and stick them on a yard stick cut in half and that should work good enough. Duct tape it to the back of your nest box and voila!!! A home made sparrow spooker. If the streamers are too thick you can pull some of the strands out so the'll blow in the wind better.