What the Bird?

Driving for work, I have a camera near me in the car.  I was driving through Leisure World (it's a gated community in Mesa, don't think like that!), and at the corner of the street I saw the tree near me suddenly sag and shake.  I looked up and noted a bird shape, large enough to be moving a good 3-4" bough of the tree.  I saw traffic coming at me, so I did a drive by shooting as I turned my corner.  This is the cryptic photo I got.

I tried to zoom in, but I still don't know enough to identify it from the few markings I can make out.  Give me time, though.  It was a hefty bird, and it seemed to sit like a falcon or kestrel, ready for an attack and a little hunched.  Though, it may just have been in an awkard position when I clicked.  I'll keep trying to find a similar photo or otherwise ID this one. 

*Update:  I think I found it!  I couldn't find any birds with dark and thin white stripes on the shoulder/scapula of wings, BUT, the black crowned night heron during mating season grows two long white feathers that fall across the back.  All the other colorings appear correct, considering the picture was taken in the shade of the tree, and they are known for hunching down in trees.  There is precedence of them in the area, attracted to neighborhood ponds (which there were nearby.)  What do you think?

Black Crowned Night Heron - Photo: Copyright © 2014 Jim Boone 2001-2010:
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