Diminutive, Active, Confident… Yellow-rumped Thornbills

By Keith Hutton on October 18, 2011 in Other

Thornbills are diminutive, endlessly active birds with fine bills, about half the size of sparrows. They are confident in the presence of humans, quick moving and familiar throughout Australia except in the far north. Some feed entirely in the foliage of trees and shrubs, others feed on the ground, and most are sociable little birds frequently seen in small flocks. Different species may appear hard to identify at first, but with a bit of practice and attention to head patterns, colours, habits, choice of habitat and calls, they can be separated.

Yellow-rumped Thornbills are the largest of the group and quite easy to identify. They are generally olive brown above and creamy below, with white eyebrows, black crowns spotted with white, a dark eye line, and conspicuous bright yellow rumps that contrast with dark, pale-tipped tails – unmistakable in flight. They are usually seen in small, loose groups moving jerkily over the ground feeding in short grass. They have familiar tinkling contact and chip-chip flight calls, and a sweet soft warbling song heard less frequently.

Yellow-rumped Thornbills are by far the best known and most widespread of thornbills that feed on the ground. They are found over almost the whole of southern Australia except in heavily forested areas and the driest deserts. They prefer short grassy areas, woodland edges, scrublands, paddocks, plantations, parks, golf courses and lawns. In the Sydney region they are uncommon in grassy woodlands, farmland and parklands, and their numbers appear to be declining. In the Eastern Suburbs they still occur in parks and on golf courses and they can be seen in Centennial Park, where they breed.

They eat mainly insects and spiders, and occasionally small seeds. Sometimes Yellow-rumped Thornbills forage in trees and shrubs, but they are primarily terrestrial though seldom far away from some tree cover, and often accompanied by parties of other small birds when feeding.

Although there is evidence for declining numbers in some major cities as a result of urban development, Yellow-rumped Thornbills generally have adapted well to suburban environments and may be common in parks and gardens. They have also adapted to agricultural lands, especially where there is remnant native vegetation. Cats probably catch and eat them, and poisoning from insecticide ingestion has been recorded in vegetable gardens. Furthermore, garden habitats favouring butcherbirds and currawongs with reduced ground cover for shelter may have led to increased predation by these species. Nevertheless, no overall decline in numbers is evident, despite significant regional variations, and Yellow-rumped Thornbills are among the top ten most common birds seen in Australia, and among the top forty most frequently recorded breeders.