It was an odd looking bird, mostly white with a featherless black head and neck. It looked like an Ibis with a down-curved bill. This led me, initially, to identify it as a black-headed ibis, but not quite. When I checked its range, I discovered there are several closely related ibises around the world. This one is the Australian White Ibis.
The ibis is known as a wading bird, inhabiting swamps, lagoons, and grasslands in all but the driest parts of Australia, and while declining in those areas, it's on the increase in urban parks and coasts. It's disappointing to learn that such an elegant bird whose African cousin is called a Sacred ibis, is known as the sheep bird, bin chicken, dump chook or tip turkey for its urban foraging habits. In the wild, they eat fish, frogs and other aquatic creatures as well as insects.
The Australian White Ibis is approximately 65–75 cm (25–30") in length, with an average height of 72 cm (28"). Males are slightly larger than females. They reach sexual maturity at 3 years. Nests are typically shallow platforms of twigs, and grass built in tall trees near water. Usually, 2 eggs are laid that incubate for 21-23 days. The young chicks will leave the nest in 48 days.
In the wild, the Australian White Ibis lives approximately 28 years.
Thanks go to 
References
Sacred, black-headed or Australian Ibis
Australian White Ibis
Images
Photos taken with my Canon SX620 HS in Sydney, Australia
@kansuze