You might have noticed the metal fence behind her, which crossed the length of the stream. This was put in place by the Department of Fish & Game to keep most of the salmon in the lower part of the stream in order to facilitate the collection of eggs for hatchery use. This created quite a concentration of salmon right at the gate, and the local bears definitely figured that out!
Here's a "making of" shot for this image sequence, courtesy of my wife. We were up on a stream bank (along with many other people watching the bear) and were remarkably close. In any other situation it would have felt too close, however, it was clear from the relaxed behavior of this bear that she was only interested in the fish, and she barely paid attention to the throngs of people watching along the shore.
And since this shot clearly shows my baseball allegiance, I'll sneak in a "Let's Go Giants!!" -- we're up 2-1 in the NLCS!