FEATURE
An explanation for the differences in body shape size and colours of the various specimens comes down to the area involved and the habitat changes they experience. The entire range in which they can be found extends from roughly Port Headland in the north of Western Australia through to Albany in the south of the state a distance of roughly 1,
500.kilometers.
born in the West for the purpose of this article I will refer only to the birds found in Western Australia and continue to use the museum reference. Platycercus or if you prefer Barnardius zonarius, belong to a family called Australian ring necks -- due to the band of coloured feathers encircling the majority of the neck -- in the case of all of the group that I am discussing the band is yellow – except in the situation of some colour mutations. The nominate subspecies P. z. zonarius is the Port Lincoln while P. z. semitorquatus is termed the twenty eight. In the most northerly area of distribution the WA museum classifies them simply as z. zonarius while other authorities recognise birds in this area as a further subspecies z. zonarius occidentalis, the northern, arid zone, or desert Port Lincoln. An explanation for the differences in body shape size and colours of the various specimens comes down to the area involved and the habitat changes they experience. The entire range in which they can be found extends from roughly Port Headland in the north of Western Australia through to Albany in the south of the state a distance of roughly 1,
500.kilometers. Now add the distance from the west coast of Western Australia to its border with
South Australia and we have an area of approximately 1,4000,000 sq kilometres a mighty big space you would have to agree. To quantify this size further, from the top of Scotland to the bottom of England would fit inside this Western Australian area almost twice, wow! It is pretty safe to assume that within such an immense area changes to the structure and colour of a species have lots of opportunity to alter and for a non-boffin I would have to suggest that is what has occurred. Let’s start with the south west corner of its range it has a colder wetter climate with extensive heavy forests compared to the northern extremity of the bird’s range. In this southern area we find P zonarious semitorquatus the twenty eight. This is the largest member of zonarious and the physical characteristics for me is very simply a green chest and green abdomen -- although in different locations some birds may show an occasional very small amount of yellow in the belly. Moving north we enter more open forest, cleared areas for farming, areas of timber and remnant scrub this is typical habitat to find P zonarious. Finally further north are extensive pastoral areas not cleared for farming but for grazing stock, the climate is classified semi-arid to arid, with oodles of very hot days. The
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