The Green Rosella
My love affair with the Green Rosella (Platycercus caledonicus) began as a 'young lad' watching these majestic birds feeding among the eucalypts in our back yard. Small flocks of up to a dozen birds would perform in the tops of the trees or forage at ground level for aviary scraps. Much later I chose to study their social behaviour for my Honours thesis at the University of Tasmania.
A repertoire of their behaviours was documented but the subject of their dominance hierarchy was first on my list of priorities. Twelve birds were placed in a communal aviary and an old, mature cock bird assumed the top of the pecking order while a very young juvenile female was on the bottom of the pile. The birds were subsequently removed from this aviary, housed in individual pens for seven days, and then released back into the study aviary one bird each day. The first bird replaced was the sub-dominant juvenile hen and the last was the previously dominant adult male. Would the original dominance pattern re-surface? To my surprise the juvenile hen now 'ruled the roost' with the adult male sub-dominant. I have frequently used this 'reversal of dominance' with 'troublesome' pairs of Rosellas to avoid cocks chasing hens or vice versa!!! But enough of this scientific banter!
The Green Rosella is the largest of the genus 'Platycercus' and opinion is divided as to where its origins lie with respect to other members of the genus. It is unusual in that it is the largest of the Rosella family yet it is an island species – confined to Tasmania and the islands of Bass Strait. The adult has a deep yellow on the breast and head contrasting with the black and green of the back with wings and tail tinged with a deep blue. A broad red frontal band lays above the beak with the cheek patches a vivid blue. In adult females there tends to be a lot of orange around the cheek patches, which increases as the bird ages. This is also true for ‘aged’ males as well!
Immature Greens take about 16 months to attain adult plumage. They start off life outside the nest as dark green birds and gradually develop their yellow colouration over successive moults. Juveniles are a dull yellowish-green with aviary birds showing far more yellow than their wild cousins. I suspect that this is a result of the richer aviary diet. However, for some reason or another, the Greens that I have seen on the mainland do not appear to be as bright as those in Tasmania - maybe it is a reflection of the greater heat and humidity? Sexing is relatively easy with the males having a far larger upper mandible than females. Males also tend to be larger both in body and across the head than females.
|Fig.1. Cock Green.||Fig.2. Female Green.|
My birds receive a mixture of grey sunflower, safflower and oats plus Peppers Small Parrot Mix. Sunflower is only fed once a week, as these birds are prone to obesity or feather loss due to too rich a diet. The millets and plain canary seeds in the Peppers Mix also means that the seed diet is as varied as possible. Apples, pears, Cotoneaster berries, milk thistles and Eucalypt branches are fed whenever available. Fresh water and cuttlefish are always supplied
Obtaining a compatible pair is the most difficult thing to do with these birds. It is preferable to obtain juvenile pairs than to try to pair up adult birds, as they appear to establish a very strong pair bond as adults. If a member of a pair is lost it is extremely difficult to convince the remaining member that taking a new mate is desirable! Over the years I have know of several breeders that experienced difficulties in re-mating surviving birds. Be prepared to be patient with your pair as one of my pairs took 6 years before commencing breeding. Incubation takes around 19 days and clutches of 5 to 8 eggs appear to be the norm. Most pairs resent nest inspection and this can lead to deserted eggs or young. The most critical factor to watch when young are in the nest is the weather! These birds cannot tolerate high temperatures when chicks are in the log - a trait they share with the Swift Parrot (Lathamus discolor).
During a spell of warm weather I once had 5 young in the nest when I returned
home from work to find the parents acting in a distressed manner. Upon opening
the log I recorded a temperature of 40 degrees C and all 5 chicks sprawled
around the log bottom. They were alive but only just. I placed them in a large
tray on the aviary floor and gently fanned them for 2 hours until they could
stand up by themselves. Knowing their tendency to desert I feared the worst
scenario. To make matters worse I was going surfing for the weekend so I quickly
rang a good friend to beg him to hand feed them while I was away and happily he
was eager to help out - as always! Imagine my surprise when I sneaked out to the
aviary and watched dad feed his charges in the tray - whew!! The forecast for
the next day was for 36 degrees C so something had to be done. The bottom of the
log was covered with Hessian strips and water was poured over it and the top
removed from the log - this worked like a charm and all five left the log
despite 3 other days of 35 C+.
On this point individual pairs vary enormously with respect to their tolerance of nest inspection as I have had pairs that would desert if you simply opened the nest box while others, as outlined above, cared little what you did! Suffice it to say know your pairs before you touch anything!
Fig.3. Pair - Hen on Left.
To me this bird is the pick of the Broadtails and it is a great pity that it is not kept in larger numbers in our aviaries in its native Tasmania. As its habitat continues to be decimated and the flocks dwindle we may rue the small numbers kept in captivity. A total export ban imposed by the old Tasmanian Wildlife Service created a ridiculous price tag on this bird, with prices of up to $1200 being paid for pairs back in the mid-1980's. It was no wonder that people were tempted into illegally trading them. Although this ban is still in force it is believed that the present day Nature Conservation Branch is considering allowing aviary-bred birds from responsible breeders to leave the state as long as strict protocols are adhered to. Hopefully a reflection of a change in attitude towards various conservation agencies and the aviculturist.
However, some years back, in order to keep Greens on the mainland you had to have a 'Category 3' license, which, on price alone, put this bird beyond the range of a large number of aviculturists. The end result was that you could purchase Green Rosellas for about $150 a pair. Fortunately with new fairer license structures and fees being introduced by many mainland states there has been a gradual reviving of interest in the Green as an aviary bird.
So if you are thinking about a new inclusion in that empty aviary give the Green Rosella some serious thought. Easy to cater for, magnificent in full colour and now available in reasonable numbers on mainland Australia. It is a pity too that Tasmanian aviculturists do not keep this bird in larger numbers -after all it is the avian emblem of Tasmania. So forget those overpriced Conures, gaudy Lories and multicoloured Ringnecks and stick with a good old Australian native. Anyway, the Green Rosella is unique in that it is an island species yet is the largest of the Rosella family - obviously not everything is smaller in Tasmania!!