From what I have observed, the Green Heron shares some traits with the bigger Bare-throated Tiger Heron. Both maintain their necks coiled most of the time, and elongate them up to twice the size of their body when they are ready to attack. Both walk in a stealthy manner, not making a single sound, as they approach to unsuspecting prey. Both are startled easily and fly far away when you are too close.
The differences are that the Green Heron is more likely to be found perching high up in the trees, and the obvious size difference; the Green Heron is pretty small, the size of a duck, while the Tiger Heron is bigger than a turkey.