Budgerigar 17–18 cm; 26–29 g. Cere blue, forehead, front of the face and throat pale yellow, last with a line of black spots; lower malar area purple; mid-crown and the area below eye back to nape barred black and pale yellow, broadening to become scalloping on mantle and wing-coverts
; underparts, underwing-coverts, lower back, and rump light green; tail dull bluish, lateral feathers with a central yellow band. Female has brownish cere. Immature duller with barring on forehead and no black spots on throat.
Australia, mainly away from coasts, and absent from the Cape York Peninsula.
Inhabits a wide variety of open habitats including open forest, savanna, lightly wooded grasslands, mallee, farmland, riparian growth, dry scrubland, and open plains, even penetrating mulga (Acacia aneura) deserts; although capable of surviving long periods without water, birds are rarely found far from a source.
In parts of range areas exist in which seasonal production of food is regular, and others where the supply is stable for extended periods, so some populations relatively predictable on a seasonal basis; in far S of range birds only present Sept–Jan. Elsewhere fairly nomadic according to water and seeding grass. In times of drought, birds move wherever conditions are more favorable, but then may be confined to these refugees as the drought intensifies, only recolonizing old areas once rainfall permits it.
Diet and Foraging
Grass and chenopod seeds were taken on or near the ground, the number of species and proportions varying with season and part of the range. In inland mid-eastern Australia birds were found to eat only seeds of ground vegetation, from 0·5 to 2·5 mm in length, with up to 39 species involved; at one site Astrebla spp. were dominant in the diet, while further inland a wider array was taken, including Boerhavia diffusa, Atriplex and Astrebla pectinata, in the hot months, with Iseilema important in the colder period. Occasionally attacks ripening grain crops.
Sounds and Vocal Behavior
Quite noisy. Commonest calls a liquid pleasant-sounding “che-lee” and a short raspy dry “krrr” or “trrt”. In groups, the birds produce a constant mellow chattering with some raspy notes mixed in.
Jun–Sept in N of range, Aug–Jan in S, but any time of year after substantial rains, and where conditions permit there may be two breeding seasons in a particular year. Often communal. Nest in a hollow in a tree
, stump, fence post, or fallen limb. Eggs 4–6 (up to 8); incubation lasts c. 18 days; nestling period c. 30 days.
Not globally threatened (Least Concern). Abundant; in favorable years in certain places flocks darken the sky and the weight of perching birds have broken eucalypt branches 4 cm in diameter. Capable of considerable fluctuations in population levels depending on climatic conditions over several years, and these levels are probably driven as much by short-term breeding success as by immigration. Livestock farming in many parts of interior Australia has required widespread artificial water provision, and some populations appear to have increased permanently as a result. Generally, however, the species is found in small parties, especially at the edges of its range. Introduced in the 1950s in Tampa Bay area, C Florida, the USA, its population there peaked at perhaps >20,000 birds during the late 1970s but declined subsequently and the last individuals disappeared in 2014; competition for nest sites with Common Starlings Sturnus vulgaris and House Sparrows Passer domesticus was probably the main cause of the decline.