It is possible that birds may occasionally disperse to the adjacent mainland: black-plumaged birds, presumably originating from Dirk Hartog Island, have occasionally been reported on the Peron Peninsula (Driskell et al. 2002; Pizzey 1980; Schodde & Mason 1999). However, due to a lack of corroborative material, these reports cannot be confirmed (Schodde & Mason 1999).
The extent of occurrence is estimated, with high reliability, to be 420 km². There is no evidence of a historical change in the extent of occurrence. The extent of occurrence is currently stable (Garnett & Crowley 2000).