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Australian White Ibis

(Threskiornis molucca)
Alternative names: "Black-necked Ibis", "Sickle-bird"
Size: 65-75 cm

Habitat
(for details refer to a field guide)

Australian White Ibises are found over large parts of the Australian continent including the east coast of Tasmania, with the exception of the most arid parts of the interior of the continent, i.e. the eastern two thirds of WA, the western half of SA and the southern half of the NT. In other parts of the semi-arid interior and the western half of WA they are present only when there is sufficient surface water, normally after major rainfall events.

Australian Ibises are found in various types of freshwater wetlands, including flooded grassland and also in wetlands of brackish water. They also scavenge and can thus be found around rubbish tips and in urban parks.

Sightings

A significant number of Australian White Ibises are permanent residents in the Narrabri region, in all wet, moist or muddy areas. After significant rainfall in the area in September 2008, hundreds of them were camped around the rubbish tip (and stayed there for months). It is interesting to note that only a few Straw-necked Ibises join them there.

There is a significant colony of Australian White Ibises that breeds in trees on a small island in Narrabri Lake.

Also sighted on a trip to the east of the Great Dividing Range, in the area from Armidale to Dorrigo and Clarence river downs (Iluka), NSW. Also spotted in various other locations along the coastline, from Urunga to Hat Head.

Photos

Lateral view of an Australian White Ibis

Dorsal view of an Australian White Ibis

Small colony of Australian White Ibises on the bank of Narrabri Lake, together with two Silver Gulls

Closer look at a flock of Australian White Ibises

A whole array of aquatic birds hunting/foraging in O'Brien's Creek at Narrabri, NSW: three White-necked Herons, two Australian White Ibis in breeding plumage, two Great Egrets, one Purple Swamphen, one Dusky Moorhen and two Pacific Black Ducks

Near-frontal view of an Australian White Ibis in flight

Lateral view of an Australian White Ibis in flight

Flock of Australian White Ibises in flight, with the characteristic black tips of the primaries clearly visible

Lateral view of an immature bird

Immature bird waiting in a tree to be fed; when they are that young they are actually still white

Here another bird being fed

Twitcher's tip

Here an example why one should never take things for granted while bird-watching: In October 2011 three birds flew over our property. The photo below shows two of them - identification as Australian White Ibis is easy.

Australian White Ibis seen from underneath

A second photo shows the remaining third bird and only closer inspection later, on the computer, showed that it had slightly different features...

The third bird turned out to be an "interloper"...

Breeding information

Breeding season: Aug - Dec Eggs: 2 - 5 Incubation period: 20 - 23 days Fledging age: ca. 49 days

The breeding season depends significantly on geographical latitude. In the tropical north Australian White Ibises breed Feb - May. Given the right conditions, Australian White Ibises can breed any time of the year. They breed in tightly packed colonies, together with other aquatic birds.

Nest

Type: Basket Material: Sticks, lined with leaves Height above ground: 0 - 20 m

Australian White Ibises can nest in trees or just above water level, e.g. on lignum. They often nest in loose colonies, together with other aquatic species.

Australian White Ibises nesting at Narrabri Lake

Another example of colonial nesting

Here a nest with three chicks in it, ready to leave any time

Eggs

Size: 65 x 45 mm Colour: Creamy Shape: Elliptical

Behaviour

Social behaviour: Communal Mobility: Sedentary/dispersive Elementary unit: Flock

Food

Ibises feed on small animals that they pull out of mud or soft soil. Australian White Ibises are also known to scavenge; they are often seen around rubbish tips.