A Big Bird

These birds are pretty big and we frequently find them standing like sentries around water features and man-made lakes in the area. I get a kick out of seeing the way they space themselves out right on the shore like this:

Here is a closer look at one of the gray ones. I like the black and white coloring on the head and the intensity in his gaze.

After spending some time with my favorite paper resource, The Complete Illustrated Encyclopedia of North American Birds, as well as a bit of time on whatbird.com I am pretty sure this is a Great Blue Heron. Click on the whatbird link above to see what I mean.

Is there any controversy this time or is my identification a good one? According to the Encyclopedia, there is also a white variety, so is that what the other big white birds are or are they gender differences? I will be looking to identify the little white bird right next to the heron soon, so if you have any suggestions, please leave me a comment, either here or on Twitter.