I didn't realize it was a rare bird until I was entering my list to eBird. Yesterday, May 28th, I saw an Eastern Bluebird at the Rocky Mountain Arsenal Wildlife Refuge (RMA).
If you go on the one-way part of the Wildlife Drive, it was towards the very end of it, not long before it turns into a two way street again. He was foraging for insects along the fence line.
Susan Rosine
Thornton