In hindsight I should have included this photograph with the previous (click here) Great Egret in the dark swamp article.
Both birds were close and at one point the Heron stopped and just watched the Egret for a long time. His body language was telling me the Egret was in for a problem but the Heron cooled off.

The Heron was feeding, the mate was on a cypress tree nearby. Perhaps that’s why he was seemingly aggressive.