The Genetics of Colour in the Budgerigar and other Parrots

An article by Peter Bergman of Sydney, Australia


The Australian Recessive Grey


The first Recessive Grey budgerigar appeared in 1992. It was a Normal Grey hen bred from a pair of Normal Violet factor Cobalts (Visual Violets) in a father to daughter mating. She was the last of four chicks to hatch. Three other chicks hatched but all died at the age of one or two days. The fourth chick would probably have died as well if left with her mother. The egg was fostered under a pair of greens whose eggs were infertile. Surprisingly the chick feathered up Normal Grey. It was doubly surprising because of the fact that only three of the 70 or so birds I had were grey factor birds. The only grey factor hen bred with that year laid a clear round. Cocks and hens are kept in separate flights, and the only grey factor cock bird was an Opaline Greygreen. Furthermore there were no Yellows, Whites, or Inos which could carry the grey factor inconspicuously. My main interest is in the dark and violet factors so I have little use for Greys and Greygreens. The Grey hen could not be easily explained away.

However, at the time I thought the most likely explanation was that the Grey was an abnormal Mauve. In 1993 the suspect Grey was paired to a Skyblue Normal. Only three chicks were produced but all three were Skyblue Normals (one cock and two hens), not Cobalts as one would expect from a Sky to Mauve pairing. The Grey's parents were paired up again as well but produced only infertile eggs.

In 1994 the Grey’s Violet Cobalt mother was paired to the Grey’s Skyblue son. Five chicks were produced in total, a Violet cock, a Violet hen, a Violet-Sky cock, and two Grey cocks. All were Normals. As far as I was concerned the result confirmed that the suspect Grey was a Recessive breeding Grey. Whether or not it is the same mutation as the long lost English Recessive Grey is an open question. English Greys are reportedly quite dark, my Recessive Greys are not particularly dark. All that can be said is that the Greys arose from Australian exhibition stock and were not derived from the English budgerigars imported into Australia in the late 1980’s and early 1990’s. For the present, it is probably best referred to as the Australian Recessive Grey.

Progress has been slow but steady with a few gains and losses. There are currently two Normal Recessive Greys and a dozen splits. The most recent Recessive Grey to be bred is a Normal Grey hen bred from a pair of Normal Skyblues. Most of the splits are either Skyblues or Light Greens.

Recessive Greys are easily distinguished from Dominant Greys once you know what to look for. The following description is for the Normal Recessive Grey:

  1. The body colour is similar to a Light Dominant Grey but somewhat patchy. Recessive Greys do not have the bluish tinge on the sides of the neck that Dominant Greys usually do.

  2. The cheekpatch is a pale neutral grey and matches the body colour.

  3. The upper surface of the tail feather is satiny grey. The quill and lower surface of the tail are black.

  4. The area of the flight feathers between the white leading edge and quill is grey like the tail feather, not black as in Dominant Greys.

  5. The rumps and backs of Recessive Greys are glossier than those of Dominant Greys.

In all other features Normal Recessive Greys are like any other Normal budgerigar. In size and quality they are similar to their non-Grey nestmates. One drawback is that their feather seems to be weaker. Their flight and tail feathers tend to fray more easily than the other colours.

The late Cyril Rogers had speculated that a Dominant-Recessive Grey composite might be very dark grey or black. Due to the second World War, attempts to breed such a bird were put on hold and by war’s end the Recessive Grey had vanished. No such composite bird has ever been recorded. At present I have a Dominant Grey split for Recessive Grey and with some luck will breed a Dominant-Recessive Grey composite over the next couple of breeding seasons.


Copyright: Peter Bergman (Sydney, Australia)


Footnote:

As a result of contact originally made through these pages, Inte Onsman of Mutavi has been able to microscopically examine feathers sent to him by Peter Bergman.

He concludes that cross-sections of feathers from this new recessive grey form do not share some of the special features of the now extinct English Recessive Grey, as described and illustrated in Genetics for Budgerigar Breeders. In fact the internal structures revealed show some similarities to those of the Slate, although the differences are sufficiently great as to produce a distinctly different neutral grey colouration.

This mutant form is thus new to budgerigar culture and the title Australian Recessive Grey is very apt.



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