Herons and egrets are closely related birds that inhabit freshwater and coastal areas. They all have long legs and long necks, and fly with their necks retracted or bent. Long legs enable them to wade into deep water, and their long necks and harpoon-like bill is used for stabbing fish, frogs, and insects. They are essentially non-swimming waterbirds that feed on the margins of lakes, rivers, swamps, ponds, estuaries and the sea. In the Derwent estuary we commonly see white-faced herons Egretta novaehollandiea, which are light blue-grey in colour with a characteristic white face. The great egret Ardea alba, intermediate egret Ardea intermedia, and little egret Ardea garzetta are hard to differentiate from one another as they are all pure white with a yellow bill. As their names imply, the great egret is largest, and little egret smallest. These birds can often be seen standing frozen at the water’s edge watching and waiting for movement by prey.