The Budgerigar is one of the most commonly kept birds in
aviculture and many people start bird keeping with a budgie or two. They come in a vast range of colours
representing different mutations and when it comes to breeding a specific one,
understanding the different genetics involved can be important to getting the
result you want. So here is a basic
introduction to understanding genetics.
Genetics 101
Now I am not trained in genetics so my understanding is only
as good as my understanding of what I have read. However, here goes.
The wild type budgie is the bright green colour that is
actually called Light green. This is a
bird whose feathers have three pigments in them eumelanin, psittacin and
advanced psittacin. Eumelanin is a black
type of melanin while psittacin is the yellow pigment. The advanced psittacin is an unusual pigment
that parrot produce that allows them some of their more fantastical colours
such as red, oranges, peaches and pinks.
When the feathers are exposed to sunlight, only the blue part is
reflected by the eumelanin resulting in blue light passing through the yellow
pigment layer and creating feathers that appear green.
From this light green form of the budgie have been bed 32
different mutations and many hundreds of variations within them. These 32 fall into four basic groups;
albinism, dilution, Leucism and Melanism.
Albinism, or albinos, are the white birds with red eyes and skin and
this is where eumelanin is either partly or totally absent. Dilution is where eumelanin is reduced and
Leucism is where it is reduced in areas.
Finally Melanism is where eumelanin in increased.
The other basic of genetics is the most complicated part;
dominance relationships. This has to do
with the parts of gene called the alleles that form into pairs to make
chromosomes. Chromosomes in birds are
the same as in humans; there are two types.
There are sex chromosomes that define gender and then there are all the
rest. An allele can be dominant to the
other allele, which means whatever it brings out will be the dominant factor in
the bird but there are also other degrees of relationships. There are also sex-linked inheritances where
the alleles on the sex chromosomes are the one that define the colour. Hopefully this will make more sense when
applied to the colours and mutations!
Blue series
 |
| Skyblue Male |
There are two main sets of budgie colours; the greens and
the blues. In a blue bird, the green
feathers turn to sky blue while the mask area on the face turns from yellow to
white. Blue birds show this colour
because they lack the yellow pigmentation that creates the green feathers in
the wild type bird. Blue mutation birds
have been recorded in aviculture dating back to 1878 in Brussels, Belgium. It was first seen in England in 1910 and
remained rare until the 1930s when they could fetch £100 per pair, around the
same price as a car.
Genetically, the blue mutation is recessive compared to the
wild type allele so when a bird has one blue allele, it will appear as a wild type
bird. Only if the bird has two blue
alleles will it look like a blue bird.
When combined with the Dark mutation, the body feathers become a deeper
blue. A blue bird with a single Dark
factor is a Cobalt while one with two dark factors is a Mauve.
Dark mutation
The Dark mutation is one that affects the colour of both
green and blue birds. When a budgie has
a dark factor, the green bird appears much the same as the wild type but has
darker body and tail feathers. These are
darker still in Olives and Mauves but all of the birds have the normal violet
cheek patches.
The Dark Green had a body colour the shade of forest green
while Cobalt is a deep blue that is like an azure shade. Olive green is a richer shade of olive,
similar to Grey-green but differentiated by the violet cheek patches. Mauve is a purplish grey that is more muted
than the Violet or Cobalt colours.
Violet Cobalt is a composition of blue, dark and violet and is a bright
shape of violet.
The dark mutation has an incompletely dominance relationship
with the wild type allele. This means
that the dark green has one dark and one wild type while the olive has two dark
alleles. In the blue series, the Cobalt
has one dark and one wild type while the Mauve has two dark alleles. The dark factor is always visibly expressed
so no bird is ever split for dark.
Yellowface
There are two varieties of yellowface mutation. Yellowface I is where the bird appears as a
normal Sky blue but the face, where it is normally white, is yellow. There are also yellow tints to the wing
markings and sometimes down the breast a degree. It can also be found in Cobalt and Mauve
variations where the yellow markings remain much the same.
 |
| Yellowface I |
Yellowface II is the other yellowface mutation and can be
combined with blue, opaline or clearwing birds to create the mutation known as
rainbow. A single factor Yellowface II
has a bright body colour that is often called sea green or turquoise while
those on a Cobalt bird is bottle green and in the Mauve variation are a mixture
of mauve and olive. A double factor
Yellowface II is similar to yellowface I but the yellow tends to be brighter.
The genetics are a little confused but it is believed that
the mutation doesn’t create a yellow face but reduce the colouring in it and
are believed to be part of the blue series of mutations.
Grey
Grey, or dominant grey, is sometimes called the Australian
Grey and is the basis for the grey-green and grey standard varieties. In a dominant grey bird, the light green
variety becomes grey green, which is a dull, mustard green, and the blue
becomes a light grey, a uniform battleship grey colour. In both the green and blue birds, the flight
and longest tail feathers are black while the cheek patches are a lilac-grey
colour. When combined with the dark mutation,
both colours become darker.
This mutation is a dominant one so even over the wild-type
bird any bird with one allele of grey will be grey coloured. It also means that a double factor grey will
look no different from a single factor grey.
Anthracite is another grey mutation but this is one is much
rarer. It is similar to the violet
mutation but the birds have black or very dark grey feathers with differing
degrees of white feathers. It developed
in Germany and most all of the birds are found in the same area but it is also
possible that it is related to the now absent English Grey mutation. Anthracite has an incomplete dominant
relationship with the wild type so a different effect presents between single and
double factor birds. In green series Anthracites,
the body colour is deeper than a Dark Green while in the blues, the colour is
similar to a deep Cobalt.
Slate is another grey shade mutation which in the blue
series birds makes a light grey colour with a bluish tone while in green birds
is a shade between light green and light grey green. Dark factor has more an effect with slate
than with grey birds where they become very dark. It is a sex-linked mutation that is carried
on the X chromosome and is recessive to the wild type. This means hens cannot be split for slate and
in cocks, the slate allele much be present on both X chromosomes to be the
phenotype.
Violet
In any bird with the violet factor, there is a visual effect
on their feather colour. It depends on
whether they carry a single or a double factor and other mutation present but
there are around 18 different combinations.
Single factor violet light green lack the ribbing on the feathers
normally found to give a satin-like appearance while the tail feathers are
paler. Single factor sky blues have a
colour between dark sky blue and medium cobalt with navy blue tail feathers.
Dilute
Dilute is one of the main categories of mutations in budgies
and comes in several varieties such as light, dark, olive, grey, suffused
yellows and grey and suffused whites. In
the wild type bird, the dilute mutation makes the body colour change from green
to yellow while the black spots on the wings, head and neck are pale grey. Cheek patches become a pale lavender and the
tail feathers are a pale bluish-grey.
Dilute light greens are often known as light yellows.
In the blue series birds, the yellow turns to white but
often suffused with blue to varying degrees.
Dilute sky blues are known as whites or suffused whites when blue is
present. Dilute cobalts and mauves are
known as suffused whites also.
Dilute is a recessive mutation to the wild type so if a bird
has a single allele of dilute, it will appear as a normal wild-type bird and
will be classed as split for dilute.
Clearwing
Clearwing is a mutation in its own right and also the
underlying variety of a number of other mutations such as the yellowwings
(combined with green series) and whitewings (combined with blue series). It combines with the greywing variety to make
full-bodied greywings and with yellowface II and opaline to make rainbow.
A clearwing light green has only slightly lighter colours
than a normal light green bird but with highly contrasting yellow wings. Similarly, with a sky blue bird, the colour
is similar but the wings are whiter. There
are pale grey shadows on the normal markings while the tail feathers are a
smoky-grey colour in the blues and grey-green in the green. Clearwings split for dilute are slightly
paler.
Greywing
Greywing budgies have a body colour that is around half the
intensity of a normal variety with wing, neck and head markings reduced from
black to mid-grey while the cheek patches are pale violet. The tail feathers are shades of grey with a
bluish tinge. When combined with the
clearwing mutation, the birds are known as full-bodied greywings, which have a
darker colour to the body and markings.
Pied
 |
| Recessive Pied |
There is a range of different pied mutations in budgerigars
and here are a few of the more common ones.
Pied budgies all have irregular patches of clear feathers that can show
up in random places around the body. These
patches are lacking in melanin pigment so just show the ground colour, which is
yellow in green birds and white in blue birds.
The remainder of the feathers are normal coloured.
The recessive pied mutation is the underlying mutation of the
Danish pied variety that is also known as the Harlequin. With recessive pieds, the areas of pied
feathers are very extensive and can result in birds that are almost clear, with
small patches of pigment. These patches
of colour are often brighter and more vivid in shade than normal.
The Australian pied mutation is the underlying mutation for
the Banded pied variety. These birds
have a nape spot, areas on the wings and breast that are clear and pink
feet.
Cinnamon
The cinnamon variety of budgies is one of the 30 or so
mutations as well as the underlying mutation, with Ino, for the Lacewing
variety. On a cinnamon bird, all the
markings that are normally black appear brown and these are darkest on the male
birds. Body colour and cheek patches
tend to be paler by around half and their feathers have a silky appearance. Their eyes of dark brown with a white
iris. It is a sex-linked mutation that
is carried on the X-chromosome and is recessive to the wild type of budgie.
Ino
The ino mutation is the underlying mutation for variations
such as the Albino and Lutino as well as a constituent part of the Lacewing
variation with cinnamon. Green series
ino birds are known as Lutino and have pale yellow contour feathers along with
white or pale yellow flight and tail feathers.
Their cheek patches are silvery-white.
In the blue series, ino become Albino, birds that are pure white with
slightly silvery cheek patches. All ino
birds have red eyes and pink legs and feet with the cere on the male bird being
grey-purple rather than the normal blue.
 |
| Albino (left) and Lutino (right) |
Ino mutations are sex linked recessive on the X chromosome
and it works by inhibiting the melanin pigment in the feathers.
Opaline
Opaline mutation budgies are known for a range of
characteristics that can be present in varying intensity. These include striations on the top of the
head that extend down to the between the wings being much reduced or even
absent. Another sign is that the dark
markings on the wings are often absent; being the same colour as the body and
giving it the opalescent effect that gives the mutation its name.
Opaline combines with yellowface II and clearwing mutations
to produce the rainbow variation. Opaline
is a sex-linked mutation carried on the X chromosome and is recessive to the wild
type.
Conclusion
To know what you will get out when you breed a pair of
budgies, you need to know exactly what you are putting in and this can take a few
generations to achieve. However once you
know the makeup of your birds, there are various calculators out
there that will tell you what pairings will produce what type of chicks and
allow you to plan going forward.
Alternatively, you can go for blind luck and get a pleasant surprise
from each egg.
