The big difference between shooting in a marsh versus a swamp is the distance of the subject. In swamps the birds are comfortable with being closer, and often initiate it themselves.
Below a heron walked in front of me and began hunting in the shallows.
I stayed on dry ground (big surprise) and the Great Blue wandered in the cut nearby.
I’m not sure if he caught anything. Eventually he casual walked the other direction.
Swamp Rookery, Magnolia Plantation, Charleston.