Very nice portrait.
I'm convinced that North American Black Bears are harder to photograph than Brown Bears or Grizzlies.
Black bears think of themselves as a prey species because they evolved when Grizzlies, Saber-tooted Cats and Dire Wolves were preying on them, so they're more likely to run away than a Brown Bear or Grizzly Bear is.
OTOH in some populated areas where hunting is not allowed such as Lake Tahoe they've learned that people are not a threat. I had to back up and maneuver to see between other people to photograph this bear, with a 280mm lens. The Forest Service was on hand to keep people and the bear separated.
(http://wildlightphoto.com/mammals/ursidae/blbear00.jpg)