Rose-Headed: A Possible New Mutation In A. Roseicollis?
By: Doug Bedwell
Several times each year, I will receive an Email or a phone call from someone who believes that they have found a brand new lovebird color mutation. Usually these "new mutations" turn out to be isolated quirks, such as incidences of the red suffusion, or they are simply some combination of existing mutations that the breeder did not recognize.
However, I recently learned of a line of birds which may very well prove to carry a new mutation. Although there are still many questions to be answered about these birds, early indications are that this color trait is consistent and distinct, and it may be predictably heritable.
These birds have appeared in the aviary of Becky Anderson, who refers to the color as "Rose-Headed," after the most striking aspect of their appearance. A picture will accompany this article, but unfortunately many of the more beautiful and subtle aspects of their coloration did not show up very well in photographs, so a thorough description of the birds is still in order. I did not appreciate just how lovely these birds are until I had the chance to see them in person.
Their most striking feature is their head color. The face and forehead are colored similarly to a normal peachfaced, but the red of the face covers the entire head, wrapping completely around much like the black hood of the masked lovebird. There is a small violet patch of color covering each ear. This patch is subtle, but is clearly visible when the birds are viewed up close.
Rose-Heads also differ from normal Peachies in that their bodies are a lighter shade of green. The color is similar to that of an American Cinnamon, except that it is noticeably brighter in hue. This lighter color is accentuated by the fact that the edges of most of their wing feathers, as well as a few of the red feathers along the lower back of the head and upper back of the neck are outlined at the edges in an even lighter yellow-green. This creates a "scaling" effect, something like the reverse of what we see in the dark edging of the American Yellow or the Greywing.
The third major difference is in the rump, which is not blue, but is the same color green as the rest of the body, while showing a hint of iridescence. Instead of the characteristic red spots found in the tail feathers of a normal Peachfaced, the tail shows a broad, full band of red-orange color, with only a hint of green at the tip.
Rose-Headed babies have been easy to identify as soon as pinfeathers come in, as they are paler in color than normal peachfaced, and the red on the back of the head shows quite clearly. They also seem to have down which is a shade more yellow than that of normal Peachfaced chicks. When young Rose-headed babies go through their adult molt, they get the familiar splotches of red "measles," just like a normal peachie, but the splotches appear over the entirety of the head, not just on the face.
The breeder of these birds has kept good records, so although there is still a lot which is not known about them, we do have enough data to make some informed guesses. I'll begin by telling you what is known about how these birds appeared, and then present some preliminary hypotheses.
THE FACTS:
The first Rose-Headed baby was hatched on January 18, 1997, and there are now six visual Rose-Heads. Five of these birds have been sexed, and all five are female. The sex of the sixth visual bird is still unknown. All of these birds have come from a single pair, named Ozzie and Harriet. Visually, Ozzie is a Normal Green, and Harriet is Medium Green. Neither shows any sign of hybridization, pied, or appears in any way to be unusual, except that Ozzie's tail has patches of red which are larger than might be expected in a normal peachie. These patches are easily visible when he is perched at rest.
The current breeder traced the birds to their original breeder, who has indicated that Ozzie's father was a Lutino. Both birds are also split to Dutch blue, as they have produced one Dutch Blue offspring. In total, Ozzie and Harriet have produced fourteen young, all of which have survived infancy. There have been six Rose-heads, five hens, one of unknown gender, one Dutch Blue, a male, and seven normal or medium greens, four cocks, one hen, two of unknown gender.
THE SPECULATION:
Though certainly much is yet to be determined about these birds, the breeder and I have established some working theories about the origin of the Rose-Headed color, and its possible mode inheritance.
The parent birds, Ozzie and Harriet, have passed the mutation on to multiple offspring. This would indicate that the mutation already exists in Ozzie and Harriet's genetic makeup, and was not spontaneously generated during their mating. If the parents carry the mutation, but do not show it, it must be either a recessive trait
carried by both parents, or a sex-linked recessive trait carried only by Ozzie, the father. Since both parents originated from the same aviary, we cannot assume that they are unrelated, so it is certainly possible that a Rose-Headed gene originated singly in some common ancestor of theirs, and is only now appearing visually. However, given that all the visual Rose-Heads for which sex is known are females, it is also possible, and frankly seems more likely, that the color is sex-linked, and that Ozzie is the sole progenitor.
With this in mind, it is an interesting additional point that Ozzie's father, as I mentioned previously, is believed to have been a Lutino. If this is correct then it is very unusual that Ozzie has produced no Lutino daughters. Theoretically, half of Ozzie's daughters, or one fourth of his offspring should have been Lutinos. Statistically, the chance of a split Lutino male producing no Lutino daughters out of fourteen chicks is less than 2%. This is not a conclusive point, but I think it is possible that the Lutino gene which Ozzie inherited from his father mutated into the Rose-Headed effect at the point of Ozzie's conception. If this is correct, then Ozzie will never produce Lutino daughters; all of the daughters which inherit that mutated Lutino gene will instead be visual Rose-Heads. If this is the case, then the total of six visual Rose-Heads out of fourteen offspring, though more than the odds would dictate, is not inconceivable.
If it is a sex-linked characteristic, it may be possible to visually identify males split for the color. As I mentioned earlier, it appears that Ozzie and at least one of his sons exhibit a much more pronounced band of red in the tail than in a normal green Peachfaced. Though this may turn out to be a useful indicator, until some of Ozzie's sons produce their own offspring, there is no way to confirm this hypothesis.
CONCLUSIONS:
Obviously, there is much yet to be learned about the Rose-Headed effect. The oldest of Ozzie and Harriet's offspring have only recently reached breeding maturity. At this writing, the oldest visual Rose-Headed hen is sitting on her first clutch of eggs, and
another mature Rose-Headed hen is awaiting the arrival of the unrelated male selected to be her mate.
It is certainly far too early to assume that the hypotheses outlined above are entirely accurate. Furthermore, until it is demonstrated that Ozzie and Harriet's children are able to pass the trait on to their own offspring, it remains a leap of faith to assume that the trait can become established at all. However, with six visual birds already present, early indications do seem encouraging. None of the birds have shown any physical problems (knock on wood), hatch rates have been good, and enough information is available to begin to make some guesses at inheritance.
It should be noted here that these birds have first appeared in the aviary of an admitted novice breeder. However, she has kept excellent records, and those records have been very valuable to her in planning a breeding program for these birds. A reminder to all of us that good breeding records can provide tremendous benefits,
sometimes in the most unexpected circumstances.
So there you have it. Is this a new mutation, or just an interesting quirk? Only time will tell. But for now, it is exciting to see such an interesting color appear, and to imagine the future color combinations it may make possible.
**** Originally published in "Agapornis World" April/May 1998. Rose-Heads are now known as Opalines.
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