In Bluebirds, the blue colour is produced by the structure of the feather - there is no blue pigment. "Tiny air pockets in the barbs of feathers can scatter incoming light, resulting in a specific, non-iridescent color. Blue colors in feathers are almost always produced in this manner. Examples include the blue feathers of Bluebirds, Indigo Buntings, Blue Jay's and Steller's Jays."

www.allaboutbirds.org/guide/Mountain_Bluebird/id

www.jstor.org/discover/pgs/index?id=10.2307/4077277&i...

I discovered last night that I had not posted any photos from the folder of photos taken on 2 June 2017. Nothing too special and mainly Mountain Bluebirds. This was just a short drive to see if I could see any of these beautiful little birds. Not sure if I will be posting any photos tomorrow, as I have a ton of things to see to, all of which have a deadline.