Bush Stone-curlew

The Bush Stone-curlew, or Bush Thick-knee (Burhinus grallarius), is a large, ground-dwelling bird native to Australia. It is a slender bird with a grey and brown plumage adorned with distinctive dark streaks. Its large eyes and long legs are notable features, and while it is capable of flight, it often relies on its camouflaged plumage to evade detection during the day.

Identification Tips

Adult Bush Stone-curlews measure approximately 55 cm in length, with a wingspan nearing 1 meter. They have a bill around 45 mm and a tail of about 180 mm. Their plumage is characterized by dark streaks over buff and greyish white feathers, with spotted markings on the wings. The underparts are streaked with dark brown over white and buff feathers. The head features a band of dark feathers over the eye extending down the neck, and a buff color at the forehead. Their iris is bright yellow, and they have olive-green legs and a darkish bill.

Habitat

The Bush Stone-curlew prefers open plains and woodlands but avoids rainforests, arid deserts, and urban or agricultural areas. They are often found in open forest, eucalyptus woodland, rainforest edges, grassy plains, and arid scrubland.

Distribution

This species is widespread across Australia, except for the West Australian coast and Tasmania. It is abundant in the tropical and subtropical north but has become rare in the less fertile south.

Behaviour

The Bush Stone-curlew is nocturnal, hunting small grassland animals such as frogs, spiders, insects, and small mammals. During the day, they remain inactive, blending into their surroundings with their cryptic plumage. When disturbed, they adopt a rigid posture or may crouch and walk stealthily into vegetation. They are known for their loud and eerie calls at night, particularly when rain is approaching.

Song & Calls

The Bush Stone-curlew's call is a distinctive "weeloo" that can be heard at great distances. Their calls increase in frequency with changing weather conditions and can sometimes be joined in chorus by several individuals.

Breeding

Both sexes care for two eggs laid on the bare ground, usually near a bush or fallen branch. The eggs are generally stone grey with brownish blotching, providing camouflage. The parents are known to defend their eggs with a frozen posture or by moving them if discovered.

Similar Species

The Bush Stone-curlew is unique in its appearance, but it may be confused with nightjars. However, nightjars are smaller and have a different flight pattern. The Beach Stone-curlew, another species of the same family, can be distinguished by its larger bill and different plumage.

Diet and Feeding

Their diet consists mainly of small grassland animals, which they glean or probe from soft soil or rotting wood. They may also consume seeds or tubers, especially during drought years.

Conservation Status

The Bush Stone-curlew is classified as Least Concern by the IUCN, with a population estimated at 10,000 to 15,000 individuals. However, the population is declining, and the species faces threats from habitat destruction and predation by introduced species such as the red fox. Conservation efforts include reintroduction programs in protected areas.