Despite the shared plumage characteristics with the purple species, the closest extant relatives of the Goliath are considered to be the great-billed and the white-bellied herons of Southern Asia.
Important habitats can include lakes, swamps, mangrove wetlands, reefs with few cool water, sometimes river deltas.
They tend to prefer pristine wetlands and generally avoid areas where human disturbances are a regular occurrence.
A diurnal and often rather inactive feeder, this heron often hunts by standing in the shallows, intently watching the water at its feet.
This is a typical feeding method among large Ardea herons and it can forage in deeper waters than most due to its larger size.
It is possible that the bill is used in a lure-like fashion occasionally, attracting fish to the static, large object submerged in the water.
The handling period is long, with herons often placing their struggling prey on floating vegetation while preparing to swallow it.
Due to its generally slow movements and handling time, the goliath is frequently vulnerable to kleptoparasitism.
In Africa, African fish eagles frequently pirate food caught by goliaths, although other large birds such as saddle-billed storks and pelicans may also steal their prey.
Occasionally, they may join mixed-species colonies including other heron species, cormorants, darters, ibises and gulls.
Although they can sometimes replace clutches, often only around 25% of eggs succeed in hatching due to various environmental conditions or predation.
The young are fed by regurgitation in the nest and, after a few weeks, can bill jab and practice defensive postures against each other.
Also, due to its size and formidable bill, the full-grown Goliath heron may not have any regular predators.