Night Heron or Little Bittern?

Saw this bird slinking along the edge of the lagoon, he never adopted the normal Night Heron posture and was always in stealth mode more like a Little Bittern. I need to find out what he actually is! As you can see he has a bluey-green cap and a light brown body with bright green legs, he matches the description of a Little Bittern more than a juvenile Night Heron. He was extremely successful at fishing and gobbled down many little fish while I watched him.