Heron Feeding Frenzy?

This Great Blue Heron appeared to be having a feeding frenzy, during the 5 or so minutes that I was watching it. Made for a great photo opportunity, but I have to wonder if this bird has lost a fear of humans? I say that, because I believe it may be the same bird that I've captured feeding at this location several times over the last few weeks.

 I took these shots with the Nikon 70-300mm VR lens at 300mm on my D700, so as you might assume the Heron was very close. Full body shots of the Heron required me to either back off, or zoom out to 125mm. Usually a Great Blue Heron would move on quickly if I came that close, but either the bird is very hungry (while nesting) or has lost the fear of humans. I hope it is the former, rather than the latter in this case.

Otherwise bird activity was low while I was out today, most likely due to the tidal conditions. Low tide periods mean that more or all the shore birds move out into the mudflats, leaving the bird sanctuary very quiet aside from the usual Fox Sparrows, Cedar Waxwings, Spotted Towhee, Red-wing blackbirds and Chickadees. There have a been a number of Virginia Rail spottings lately (I spotted one earlier this month), but I haven't got any shots of one yet.