The name "rainbow" was first used by Keston Foreign Bird Farm to simply describe a colourful composite variety in their budgerigar breeding aviaries. Keston were undoubtedly the first people to breed such birds in any quantity although odd specimens had previously been bred both in Britain and on the Continent. The Keston strain belonged to the yellow-faced and golden faced opaline white wing blue and cobalt kinds and it was these particularly coloured birds that they called "rainbows". They did not include the mauve coloured forms in this tradename, as these birds are so much duller in their colouring although they were aware of their potential in the breeding quarters. In addition, they excluded the yellow-faced and golden faced forms of the opaline whites of deep suffusion and Greywings. So far as Keston Foreign Bird Farm were concerned the Rainbow began and ended with the yellow-faced opaline/white wing blues and cobalts and the golden faced opaline/blues and cobalts. The violet cobalt (visual violet) and violet sky blue forms, which we know today were not generally known at that time.
We now come to the interesting point of the kind of yellow-face and golden face used in the production of the Keston "rainbows". I have seen and handled numerous specimens of pure bred Keston "rainbows" and I feel certain they belong to the Mutant I kind and not the Mutant II form which gives the heavy yellow overlay. The majority of Mutant I birds show yellow on face, part wings and tail, with the body colour showing a change of shade mainly at the top half of the chest. I feel sure that the opaline character used in the production of these birds was the Australian one as this is brighter than either the British or Continental opaline mutations. The white wings used were I think derived from pure bred Australian birds that had not been crossed with any other strains. The combination of these particular characters produced the brilliantly coloured multi-hued "rainbows" of the Keston strain.
Although many of the "rainbows" we see today are quite brightly coloured birds, very few of them come up to the intense colouring of the original Keston stock. I believe that this is mainly due to the constant outcrossing with various strains of whites, yellows, and Clearwings. The Keston birds were undoubtedly the result of very careful selective breeding from richly coloured stock.
First Appearance of Yellow-faces
I was looking through some old Budgerigar Bulletins regarding the first appearance of the yellow-faced character and it would seem that the mutation, or mutations, should I say, were first reported in No. 39 of September 1936, having first been bred in 1935. In an article I wrote in No. 43, June 1937, I gave a description of one the yellow-faced kinds, I quote "Now for a few words about the colouration of these birds; actually it is not only the face that is yellow, but the tail and wings are also affected. For an example, we will take a yellow-faced sky blue; the crown and mask are yellow, the body solid sky blue in nest feather, greenish tinted when adult, the tail like that of an ordinary green bird, the greater portion of the wings are also as in a green bird. It amounts to this, all the extremities of these blue birds are yellow tinted, and this makes a very fascinating combination of colour". This was of course a description of a normal yellow-faced sky blue that we now know as Mutant I and I have compared this description with known Mutant I birds I now have in my aviaries and it is identical. There is we know a variation in the amount of yellow carried and shown by individual Mutant I birds with those being bred especially for exhibition showing the yellow mainly in the facial area. In all cases there is a change in the tone of the blue colouring, in some instances only very slight and in others quite noticeable. Similarly birds having the deeper or golden faced colour can follow the same pattern as the yellow-faced birds mentioned above.
At the present time we have several distinct races of yellow-faced birds and of course their combinations and their presence in the composite "rainbow" type makes a great difference to the visual colour shown by these birds. If there is too much yellow overlay then the composite bird becomes very difficult to distinguish from a green and consequently the good rainbow colouring is lost.
It would seem to me that to comply with the requirements of the show bench, breeders of the normal types of yellow-faced birds have, by selection, produced Mutant I birds, where the yellow is more or less confined to the face and tail with just a trace on the wing butts. Whereas breeders of "rainbows" have by their selective methods bred birds with more widespread yellow areas. In the course of doing this they may have also occasionally used other yellow-faced mutations to cross in with their strains in an endeavour to add or maintain brilliance of colour.
Another thing that undoubtedly has a bearing on the overall appearance of "rainbows" is the kind of opaline pattern character used. As we know there were 3 separate opaline mutations involved in the ancestry of our present day opalines. Although these 3 opaline characters have the same broad overall characters there are slight recognisable individual differences in each kind. The form used by Keston was I think of the Australian mutation where the colouring is very bright with good clear mantles and heavy rich wing suffusions. It can well be imagined why this kind were used in preference to the less intensely coloured Continental or the more heavily marked British mutations. In the general run of opalines today the three kinds are blended together and the odd recognisable specimens of the individual forms only turning up occasionally. The opaline pattern character has decided effect on the visual appearance of "rainbows" particularly on the wing areas where it does or does not give the desired variation of colouring according to its own peculiarity.
Difference In The Actual Colour Arrangements
Breeders of Clearwings know there can be quite a lot of difference in the actual colour arrangements of Whitewings belonging to various strains. Here again the kind of Whitewings used to breed "rainbows" can have their effect on the composite type. As far as records go there appears to be only one Clearwing mutation, which originated in Australia and it is from these birds that our Yellow-wings and Whitewings have descended. Here again a great many of our Clearwings differ somewhat in their colouring from the original imported stock which were generally so much more intense in body and clearer in wings. When the Whitewings character is combined with yellow-faced and opaline the clearness of the wings is lost being overlaid by the patterning of the opaline and the yellow tinting of the yellow-face. This being the case it means that it is not necessary to use Whitewings that have good clear wings providing they have the needed depth of body shade for breeding "rainbows".
Keston Foreign Bird Farm only called the composite birds with sky-blue and cobalt body shades by the descriptive trade name of "rainbows" and did not include any of the other possible shades. At the present time we can well add the violet sky-blue and violet cobalt shades to this "rainbow" group. "Rainbow" is of course now only used as a name by some fanciers to describe birds of certain mixed characters but the correct description of all birds having yellow yellow-face (golden-face), opaline and Whitewing characters in their make-up irrespective of their body shade is yellow-face (golden-face) opaline Whitewing. I think that the correct name must always be used when describing these composite birds and also for show purposes although amongst breeders the short name of "rainbows" can well be employed.
Without a doubt these birds are extremely interesting to breed and give fanciers a great deal of scope for trying out unusual pairings and increasing their knowledge of colour inheritance. Many times have I had the pleasure of seeing Ken Grays "rainbows" flying in his aviaries and I must say it is an amazing sight to see a collection of these intensely coloured budgerigars. There is of course still plenty of room for improvement in type and size in this composite variety and it is hoped that each season we shall see a steady improvement all round with more specimens being exhibited.