Straw-necked Ibis

The Straw-necked Ibis is a strikingly patterned bird with a glossy black back and wings showing an iridescent green-purple sheen, contrasting with pure white underparts and a white neck. Its bare, dark head and long down-curved bill are typical of the ibis family, and breeding adults develop distinctive stiff, straw-like yellow feathers projecting from the lower neck, which give the species its name.

This is one of the most nomadic wading birds in Australia, capable of moving huge distances and gathering in massive flocks wherever grasshopper or locust outbreaks provide abundant food, making it an important natural control on agricultural pests.

Key field marks

• Glossy black back and wings with iridescent sheen, contrasting with white underparts and neck
• Bare dark head and long down-curved bill
• Straw-like yellow feathers on the lower neck in breeding adults
• Often seen in large, wheeling flocks

Similar species

The Australian White Ibis shares the bare dark head but has an all-white back, unlike the glossy black back of the Straw-necked Ibis; the two often occur together and are easily told apart by overall body color pattern.

Habitat

It favors shallow freshwater wetlands, wet grasslands, and farmland, particularly pastures and crops experiencing insect outbreaks.

Range and migration

The species is widespread across Australia and extends into New Guinea and nearby islands. It is highly nomadic, moving unpredictably in response to rainfall, flooding, and insect abundance rather than following a fixed migratory pattern.

Behavior

Highly gregarious and nomadic, Straw-necked Ibis form large flocks that can number in the thousands, moving across the landscape to exploit temporary insect abundance, and are often seen foraging in open paddocks alongside other wading birds.

Voice

Low grunting croaks, given mainly at breeding colonies.

Feeding

It feeds mainly on insects, particularly grasshoppers and locusts, walking through grassland and crops to snap up prey, making it valuable for natural pest control.

Nesting and breeding

Colonial nester, often in enormous mixed colonies with other ibis and waterbirds, building stick nests in trees, shrubs, or reeds; clutches typically contain 2-4 eggs.