Eyrean Grasswren

The Eyrean grasswren, Amytornis goyderi, is the smallest member of its genus, measuring a mere 14–16.5 cm in length. This diminutive bird is adorned with a deep, finch-like bill and exhibits subtle sexual dimorphism as well as regional variation in plumage.

Identification Tips

Adult males boast a head of reddish hue with striking white streaks, while the neck and upper body range from dull to bright rufous-brown, intricately streaked with dark and white lines. The face is predominantly white, save for the rufous forehead and a thin, incomplete white eye-ring beneath the eye. The tail and upperwings are dark grey-brown, complemented by off-white shafts and light brown fringes. The underbody is white with a buff-brown wash extending to the flanks, legs, and underside of the tail. Females are similar but exhibit brighter rufous-brown flanks and may have slightly paler legs with a more pronounced purplish tinge.

Habitat

The Eyrean grasswren is found in habitats dominated by sandhill canegrass tussocks on dune crests and slopes, often accompanied by speargrass, spinifex, and dune pea.

Distribution

This species has a patchy and restricted range, confined to the dune fields of the Simpson and Strzelecki deserts in Central Australia, with populations in South Australia, southwestern Queensland, and the Northern Territory.

Behaviour

The Eyrean grasswren is a sedentary and cryptic bird, typically encountered alone or in pairs, and occasionally in small groups. It is adept at remaining concealed within canegrass tussocks and is known for its distinctive "half running, half flying" movement across the dunes.

Song & Calls

The vocal repertoire includes contact calls and songs performed by both sexes, possibly serving territorial defense or group cohesion. Songs are characterized by "beautiful silvery cadences, pip trills, and long bursting staccatos," audible from considerable distances.

Breeding

Little is known about the breeding habits of the Eyrean grasswren. Nests are constructed by females and are typically wedged into tussock stems close to the ground. Clutches usually consist of 2-3 broadly oval eggs.

Diet and Feeding

The diet is balanced between vegetation and invertebrates, with foraging behavior involving small hops between and within clumps of vegetation, occasionally shuffling feet to uncover hidden food items.

Conservation status

The IUCN currently lists the Eyrean grasswren as Least Concern, with populations believed to fluctuate with seasonal cycles. Threats include habitat degradation due to grazing by introduced species and livestock.

Ornithological history

The Eyrean grasswren was first described by John Gould in 1875 following its discovery near Lake Eyre. Despite its elusive nature and the challenges of studying it in its remote habitat, the species has been the subject of intermittent research and observation.