The Australian Little Bittern is a small, secretive bird found in the tall reedbeds and rushes of wetlands.
The Australian Little Bittern is the smallest Australian heron. It is only 30cm long and weighs around 85 grams. In contrast to most other herons, the sexes are distinguishable. The male has a black back, whereas the female’s back is brown. Both have a black or dark crown, a rufous or buff neck, a black tail, and a dark-brown double-stripe from throat to mid-belly, flanked by broader buff streaks. The juvenile is similar to the female except it has bold brown/black streaks on much of its body and rufous tips on most feathers.
In flight, the male shows a marked contrast between dark back and primaries, and the buff upperwing coverts. This contrast is reduced in the female and slight in the juvenile.
Males utter a monotonous orrk-orrk-orrk, with notes uttered at 0.5 second intervals, in a sequence lasting about 10 seconds. Females are thought to give a call in a different pitch. Calls can carry at least 100 metres on still evenings. Sounds like wood being slowly sawed or call of frog. Bird call recorded by: Drew Davison
The Australian Little Bittern occurs locally across south-eastern and south-western Australia (during spring and summer). Its status in northern Australia is uncertain. However, recent records suggest that some sites (mostly artificial) support a resident breeding population. More information is needed, especially in wetlands with populations around the Ord River in Western Australia, Northern Territory and Queensland. Regarded as a winter visitor to southern Papua New Guinea.
The Australian Little Bittern occurs in diverse freshwater habitats, mainly where tall rushes, reeds, Typha (cumbungi), shrub thickets or other dense cover is inundated by at least 30cm of water. It can be found in vast swamps, but unlike the Australasian Bittern, it often inhabits small patches of dense wetland vegetation such as Typha along drains or in small urban lakes.
The Australian Little Bittern is not much larger than small rails but, unlike them, it rarely comes out onto mudflats or into the open, preferring to remain within or on the edge of wetland vegetation. It is a migratory species in the southern part of its range. They are most vocal during the breeding season in spring and early summer, around sunset and sunrise. They have been found to be much more vocal on warm, calm evenings (compared to cool windy conditions).
Australian Little Bitterns feed on a wide range of crustaceans and insects, including shrimps, prawns, freshwater crayfish, dragonfly larvae, water-boatmen and waterbugs, as well as fish and tadpoles. They perch low on reeds and stems, and patiently wait to stab swimming prey.
The breeding season of the Australian Little Bittern occurs from mid-October to late January. Their nest is a flimsy platform of seedheads, stems, fine twigs, grass, bark, reeds, fine sedges and rushes, sometimes with woven canopies, possibly made by roosting Purple Swamphens. They lay 3–4 eggs which are incubated for 16–21 days by both adults. The fledging period is 25–30 days. Young Australian Little Bitterns remain with their parents for another two weeks, first clambering on reeds around the nest at 9–14 days.