Morphological variation in the white-tailed black cockatoo, Calyptorhynchus baudinii, in Western Australia: A multivariate approach

Abstract

A multivariate statistical study is made of morphological divergence in external body dimensions and in skull shape between two forms of C. baudinii - the long-billed form, C.b. baudinii, and the short-billed form, C.b. latirostris. Complete separation of the two forms is established, based on external morphology and on skull morphology. The degree of morphological divergence poses the problem of assigning taxonomic status to the two forms; the complete morphological separation revealed by the multivariate approach is greater than that normally associated with subspecific status, and, together with documented ecological differences, may indicate full biological species status. A comprehensive study is under way (by D.A.S.) to establish the reproductive behaviour and breeding ranges of the two forms.