Just as I was about to leave the one of the parks on the Mississippi River that I visited today, I heard bluebirds singing in a nearby tree, so I tried to track them down. They never let me get close, but the contrast of the males’ bright blue feathers against the rusty brown of old oak leaves was striking enough to make some nice photos.
The bright blue really makes this bird stand out, but the rusty brown breast feathers just matched the color of the oak leaves.
Some males seem to be much bluer than others, and the females (upper left) have paler rusty breast feathers and much less blue in their wing and tail feathers.
My long-term blog readers may recall from earlier posts that the blue color is structural, rather than the result of a pigment. Tiny air spaces in the feathers contain particles (like dust) that scatter and reflect short wavelengths of light so that the feathers appear blue to our eyes. In the wrong light (i.e., indirect), the bright blue feathers just look slate gray.
A poorly lit subject without direct sunlight on his blue back looks a little less blue.
Bluebirds are not very cold tolerant birds, and we may still experience more spring snowstorms and sub-freezing temperatures, so I hope these guys haven’t arrived too early.
On a recent sunny day, a flock of Eastern Bluebirds chased each other in and out of what I presume were roosting holes in a dead tree. At times they behaved like woodpeckers, scaling the snag vertically, but there were obviously no hidden insects in a snag this old and rotten. When they tired of this game, they settled down to some intensive foraging, searching the vegetation for the flies and bees that were pollinating the flowers.
Yellow-rumped Warblers (left) seemed to follow the Bluebirds around as they chased insects from high or low perches. Maybe the warblers caught the insects the Bluebirds missed.
They probed into every nook and cranny looking for hidden prey. This bird stared at the mushroom on the rotten log for some time, before deciding it had nothing to offer.
When I stood quietly (for many minutes), Bluebirds would come within 15-20 feet and pose for my camera.
A mottled background of drying prairie grasses was the perfect contrast for this bird’s bright blue and russet colors. I’ll miss these cheerful little birds when they fly south.
This has to be one of the most endearing little birds we see in Minnesota.
I found them this year in exactly the same place (same trees) I first saw them last year, and within a week of the same time of year.
Some were hunting for berries in the bushes. Some were hawking for insects from a perch. Their little social group flitted around me and over me, chirping away like they were gossiping about me pointing some big old black tube of a lens at them.
Eastern Bluebirds are definitely one of my favorite photo subjects. Like their larger cousins, the Robins, Bluebirds eat a mixed diet of insects and fruit in the winter. Availability of food determines whether Bluebirds stay in an area year-round, and Minnesota doesn’t offer much in the way of insects during the winter. Further south Bluebirds might feast on berries of dogwood, sumac, hawthorn, virginia creeper, and wild grape, even blackberries, poke berries, or honeysuckle to supplement their insect diet.
I have Bluebird boxes in my backyard (which the House Wrens love), but have never seen a Bluebird there. Maybe I need to plant some of these fruit-bearing bushes and trees.