The Western Corella, also known as the Western Long-billed Corella, is a white cockatoo endemic to the south-western regions of Australia. This medium-sized, stocky bird boasts an erect white crest, a pale yellow underwing, and a long pointed bill. Its eye skin is a blue-grey, and it features a crimson pink coloring between the eyes and beak, with a small pink patch on the throat. The upper mandible is notably long-tipped, and the legs are dark grey. The plumage of the underparts may appear stained or dirty due to their ground-feeding habits.
Sexual dimorphism is not present in this species, making it challenging to distinguish between males and females. However, males are generally larger with a deeper alarm call. The lack of "green" dyck-texture in the plumage is a distinguishing feature of cockatoos, including the Western Corella.
The Western Corella inhabits undulating farmlands with significant clearance for wheat and sheep farming, with remaining native vegetation confined to isolated patches and road reserves. Critical habitats include large eucalypts and other trees, alive or dead, in forested areas or as lone paddock trees and roadside vegetation.
Two geographically isolated populations exist in south-west Western Australia. The northern wheatbelt population consists of 5,000â10,000 birds, while the far south-west population is approximately 1,000 strong. The species was once common but has experienced a decline since colonization.
Western Corellas are social and can form large flocks of up to 700 individuals. They are known for their raucous behavior and can be seen moving between feeding locations. Breeding pairs are stable, though some divorce is observed. The birds show strong natal area fidelity, with some returning after years of absence.
The call of the Western Corella is a wavering falsetto with eerie qualities, accompanied by various shrieks and squeaky conversational tones.
Nesting occurs in hollows of large eucalypt trees, with a preference for trees with open canopies and dead limbs. The breeding season starts in August, with clutch sizes ranging from one to four eggs. Both parents share incubation duties, and the breeding success rate is quite high.
The Western Corella's diet includes wheat grain, native seeds, bulbs, corms, and insect larvae. They have adapted well to agricultural landscapes, exploiting food supplies provided by human activities.
The Western Corella is listed as Least Concern by the IUCN. However, Muir's Corella, a subspecies, is considered Vulnerable with a population of around 3,000 individuals. Threats include illegal shooting, poisoning, habitat loss, and competition for nesting hollows. Conservation efforts are underway to address these threats and protect the species.