Both the sexes and immature birds have the same appearance. They feed mainly on seeds of weeds, eucalyptus trees, introduced and ornamental plants, and insect larvae. They sometimes severely attack fruit. The Western rosella is a common bird in the south-west, living in forest or remnant patches of native vegetation near farms. Tail and wing feathers are blue, green and black.
Immature birds are a dull green, with no distinct cheek patch.
Western rosellas cause little or no economic loss to fruit growers. Although they may be seen eating fruit in orchards, they generally feed on fruit that has previously been damaged in some way. Image White-tailed Black cockatoo . The two species are almost impossible to distinguish from one another, even at very close range. Both cockatoos are large, black birds with white cheek patches and prominent white patches on the tail feathers.