Flint, Michigan area lower peninsula: Mounted nestbox March 5th and 1st pair of bluebirds showed up March 8th, 1:15

Both m/f entered the nestbox a few times. Saw them again at nestbox Mar. 13, 1:00

I will keep you updated on nest building and more. Post anything you are seeing relative to bluebirds as well.

Homesite
http://spiralnexus.net

M/F BB's are more active at protecting the box, still no nesting material but the activity looks good at this point. Trapped 5 male HOSP so far and there's more of them. Temp around 46 - weather has been good. Here's one of my info pages on House Sparrows - Invasive Species:

http://spiralnexus.net/penbl/sparrows.htm