Get Low (With Apologies to Robert Duvall)

All herons and egrets use similar fishing techniques, but the smaller herons such as this Snowy Egret will use this method more commonly than the larger birds. That is probably because the smaller birds having shorter legs are closer to the water. 

Notice the angle of surface of the eye in this photo and the last - a good example of something I have noticed but have never had confirmed by reading about it. I am pretty sure through simply observing them over a long period that herons have the ability to turn their eyeball so that instead of looking straight out to the side (which would be monocular vision), they can angle them forward allowing them to look down their bill and out in front of them (which would be more like binocular vision). If you study this photo, you can tell the snowy is looking at the spot more or less in the middle of the water ring.

You would think the fish could see the bird as well as the bird can see the fish - and maybe they can - but just don't realize they are a predator. The snowies move as though they are in slow motion when they fish like this. Because their legs are just long enough to keep them above the water level it makes it easier for them to get low.

Once the fish become aware of the presence of a predator, they become a little freaked out as in this photo where, just by chance, I caught one jumping out of the water. If the snowies see you as non-threatening, you can get pretty close. It requires going to a spot, standing fairly quiet, and letting them eventually come to you. They have come as close as about fifteen feet from where I was standing - pretty close in a wide open area where they are free to go wherever they want.