Camouflage is a survival technique widely use by birds.
Female hummingbirds often use it to shield their nest and chicks from predators.
A recent study reported in Audubon.org has found that some birds have an awareness of their own individual camouflage markings and find nesting grounds to take full advantage of their individual coloration.
This brought to mind my first close encounter with a nesting Rufous-tailed Hummingbird.
She had built a nest in a lemon tree. Even after the nest was pointed out to me, I could not find it. From a short distance away, it looked just like a lemon. I had to wait until the Mother arrived to feed her chicks so that she could guide me to the location of her nest.
Nearby lemon.
Nest when the mother is not present and the chicks are hiding.
Mom inspecting her nest. Note the chick's beak at the top of the nest.
Feeding time brings out her hungry brood.
For more on bird camouflage: http://www.audubon.org/news/are-birds-aware-their-camouflage-new-study-suggests-so