Taxonomy
The Cape Parrot is a short-tailed moderately large bird with a very large beak used to crack all sorts of hard nuts and fruit kernels, especially those of African yellowwood trees Podocarpus spp.. This contrasts with closely the related savanna species (Poicephalus fuscicollis) which feeds on and a wide variety of tropical woodland trees such as Marula, Commiphora spp. and Terminalia spp. These species are sexually dimorphic, with females typically sporting an orange frontal patch on the forehead. Juveniles also show a larger orange - pink patch on the forehead but lack the red on shoulders and legs of adults. These plumage characteristics vary among individuals and among the three recognized forms.
There are conflicting interpretations of the classification of this species due to the existence of three geographically separated but closely related forms that differ in habitat, size and plumage. The dominant view of the ornithological community, especially in Africa, considers these as two species, with the temperate, montane forest dwelling Cape Parrot, P. robustus distinct from the savanna species, P. fuscicollis, including the Brown-necked Parrot, P. f. fuscicollis of West Africa and the Grey-headed Parrot, P. f. suahelicus of eastern and southern Africa. This view is reflected in the 2011 IOC World List (adopted by many, including Wikispecies, as the global standard) along with recent reviews and field guides from Southern Africa. These may in fact be three separate species but this view needs substantiation through studies of plumage, ecology and genetic variation within and among the two forms of P. fuscicollis. The multiple species interpretations are supported by the lack of overlap in distribution between the three forms, by the distinct biomes and dietary preferences of the Cape Parrot (P. robustus) and the other two forms (which occur in different types of tropical savanna) and by limited data on mitochondrial DNA differences among forms. The Birdlife International taxonomic checklist of the world's birds conflicts with these sources by considering all three forms as subspecies of a single species Poicephalus robustus. This disagreement impacts on the perceived global conservation status of these parrots.
The name Cape Parrot only applies strictly to the form in South Africa. The name Un-cape Parrot has gained limited popularity as a general name for the two savanna forms (as "Brown-necked", used by most sources, is an inaccurate description of the "Grey-headed" form in the east African savanna).
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