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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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