In Zambia there are maybe 500 to 1,000 individuals, mainly found at Liuwa Plain National Park, Kafue Flats and Lake Bangweulu in some years but there are no confirmed breeding records.

There is a single confirmed report of unsuccessful nesting in the Nylsvley Nature Reserve in the Limpopo Province of South Africa.

[5] The slaty egret is an inhabitant of floodplains, freshwater marshes, and temporary shallow wetlands, it shows a preference for areas where the water levels are falling back from their peak following seasonal rains.

Slaty egrets have been observed to be more numerous on floodplains which have been subjected to fire, and it is often found alongside the red lechwe antelope (Kobus leche).

The preferred breeding habitat is beds of Phragmites reeds, but it will also nest on islands of vegetation such as water figs (Ficus verruculosa), Acacia species or Senegal date palms (Phoenix reclinata).

[5] Slaty egrets are largely sedentary but they show some movement in response to rains, which cause seasonal variations in wetland conditions.

Infrequent records from countries abutting the main range i.e. Malawi, Zimbabwe, Mozambique and South Africa, demonstrate that slaty egrets are somewhat nomadic.