Reader Question on Naming Bourke Colors and More

QUESTION:

Hello Gail,  Last week, I acquired a pair of Bourke's.  The male is a dark-eyed Rosey, and I believe the female is a red-eyed lutino.  I've attached a picture of them.  What would be the correct terms for their mutations? 

They had two tiny fuzzy little dark-eyed chicks when I got them on the 26th of this month (picture taken today is attached).  I am assuming they hatched on the 24th and the 26th.  With my other parrots, their eggs tend to hatch two days apart.  Is it the same with Bourke's?  There were several other eggs, but some were not fertile, two were no longer viable, and I'm not sure about the other one.  I don't know if it's a DIS or not at this point, so I'm just going to leave it alone.

The father is doing a great job of feeding the mother millet, a safflower seed blend, pellets, and freshly-chopped veggies.  The mom comes out occasionally, but is in the box probably 90% of the time. 

I've raised parrots (green-cheek conures, parakeets, English budgies, parrotlets, and cockatiels) and even doves for years, handfeeding all but the doves.  However, as I mentioned above, I'm totally new to Bourke's, and I want to become educated on them.

Though I've raised parrots for years, I'm not at all good with genetics or being able to keep mutation names straight.

Will you please explain to me the difference between lutino and rubino?  I understand a rubino to be a cross between a rosey and a lutino.  And I understand that a rosey is another word or opaline.  Is that correct?  But what are the differences in appearance? 

What exactly makes a fallow a fallow?  Can you have a dark-eyed lutino or rubino, or are the eyes always red?  Can a rosey have red eyes, or will they always have dark eyes?  Can any of the offspring between my pair be a normal Bourke's, or will they definitely be rosey or lutino or maybe even rubino? 

I saw in a video of yours that you band on approximately Day 9 (or when their little eyes open).  With all of my birds, I tend to band on Day 8, but 9 works for me if you think that's best.  I've read elsewhere that the English budgie/parrotlet/parakeet band is appropriate.  Do you agree?  I just so happen to have this size as I've raised may of those chicks.  Thank you in advance for sharing your expertise!  - Dana

Dana's mated pair.

Dana's Lutino and clutch.

ANSWER: 

Hello Dana, 

Wow so many questions, all good ones though. All Lutinos or Rubinos have red eyes. All fallows have red eyes. To be fallow, a Bourke will have gray edged wings instead of black, and red eyes. Gray can be very dark or very light. Bourkes that are fallow can be any shade of rose (even dark rose), or any shade of pink, but will always have lighter wing edges and red eyes if they are fallow.

Lutino and Rubino are really the same except that to be named Rubino, a Bourke must have rose or pink all the way down its back to the beginning of its tail. Like the bird in your picture, a Lutino can have some pink on its back, but it doesn't reach to the tail. Instead part of the back or rump is yellow. Some Lutinos are all yellow from back of their head to their tail, others like yours have more pink.  

A Rosy (my preference for spelling, although maybe I'm being out-numbered by Canada and Europe who write Rosey with an "e") ... A Rosy Bourke always has dark eyes, otherwise it would be a fallow. A Rosy Bourke always has dark-edged wings. 

The color of your babies could be normal if the male has a normal parent or grandparent. Odds are better that they will be Rosies. Note that normal babies in the nest develop dark feet, whereas a Rosy will have light colored feet. Occasionally, a Rosy will have feet that are not pink, but slightly between the dark color of a normal and a Rosy. Those, I believe, are Rosies that are split to normal. 

Bourkes with dark eyes, cannot be Lutino. However, your hen could produce Lutino males. She can only carry the gene for her own color. She decides the sex off all the offspring, as you may know from raising other birds. Birds are different in this way from mammals. In birds, it is the female that determines the sex, not the male. Your male, however, could possibly be split to another color beside his own. Only male Bourkes can be split for another color. If you know the color of his parents and grandparents, that helps... 

With bands, you can use either Budgie or English Budgies sizes. I have only used the smaller Budgie sized bands although the site I get them from (L&M Bird Bands in San Bernardino, CA), says that English Budgie bands work too. My Linnies used Parrotlet or Lovebird sized bands, and those would not have worked for my Bourkes. Although I band at 8 or 9 days, I'd keep checking your babies. That timing works best for clutches of four, five or six. When there is only one or two babies, they grow faster as they get fed more, and might need to be banded earlier. :-)

I highly recommend a copy of my newly published, "Rosie Bird's Guide to Small Exotic Birds."  In that book I tried to answer most of the questions I frequently get. It also has a chapter on egg binding and what to do in an emergency. There is also a chapter devoted exclusively to Bourkes, my favorites.

Here is a link to it on Amazon in the USA, but it is also available from Barnes & Noble and other booksellers, as well as Amazon in most other countries. Please do a review ... I will greatly appreciate it. Thanks!    

Rosie Bird's Guide to Small Exotic Birds by Gail A. Lewis

Peace & Blessings,

Gail

www.amazon.com/dp/198676348X/

BOURKE PARAKEET BABIES AS THEY GROW, a Rosy, Lutino, Rubino & a Normal

Peaches and Storm's first clutch. She laid five eggs and hatched them all, but one red-eyed youngster disappeared within the first few days. The other four thrived. See them completely grown up at the end of this video.

Peaches is an Opaline Fallow Rosy hen out of Rosie and Pretty Boy, both Rosy Bourkes with dark eyes. Storm is a Normal Bourke. His father is a Lutino (yellow) and his mother is a Rosy. They produced a very diverse, beautiful clutch!

Peace & Blessings!

 

 

Bourke Parakeet Babies, Four Different Colors in Same Clutch

Had a request for updated photos of our recent baby Bourkes. We were preparing for my husband's surgery last Monday, hours away from home. Everything is going fine, but he will have at least six weeks before adequately recovering. Being a caregiver takes time and energy away from other endeavors.

The Lutino hen before her feathers were all in.

Sweet little Rubino, my favorite actually.

It's been quiet among most of the birds. Only one pair is currently producing. All others are on vacation until next year. Peaches and Stormy had their very first clutch later than everyone else.

Rubino in front, a Normal, Lutino and Rosy.

This beautiful mixed clutch is a thrill to get. Stormy is a Normal Bourke male who is split. His father is a Lutino and his mother is a Rosy. A grandparent must be a Normal, since he is. Peaches is out of our Rosie and Pretty Boy, both are Rosy Bourkes. Peaches, the mother of this clutch, is an opaline fallow with red eyes.

We're getting feathers here and very alert.

Only one young pair, Peaches and Stormy, have a nest box. All others had their three clutches in Spring and Summer, so will wait until next year.

We're growing up! Dad at door, Mom in center.

Mom in center, standing. Only 3 babies showing, but there are 4.

Here we are at six weeks, fledged and weaned already.
Rubino in front, Lutino and Normal. Rosy below.
Photo taken October 24, 2015.


PEACE & BLESSINGS TO ALL!

 

Fallow Bourke Parakeets, More on Coloration

The photos below were sent by Kenneth and Karen Shelton of their new baby Bourke Parakeets. I was surprised to see a Normal Bourke with red eyes and sent these to Su Yin for her expert evaluation. Here is her comment:


A Fallow Bourke, possibly
Pale Fallow if toenails are clear.

"The red eyed chick is a fallow. From the way it looks, I would guess pale fallow, possibly male. If it has clear toe nails, it'll most likely be a pale fallow, and if it does end up getting more blue on it's brow, it'll be a boy.

There are probably at least 3 different fallow mutations. All are autosomal recessive, meaning both males and female will need 2 copies of the mutation to show the mutated appearance.

Young Normal Bourkes, Fallow at far end.

In this case both parents are split to fallow. I doubt the normal father is split to opaline aka rosey since none of the chicks are rosey. The rest of the 3 chicks are normal with boys split to rosey (due to the rosey mother). All of the 4 chicks can be either gender - you can't tell from the genetics. All the normal chicks may also be split to fallow, but there is no way to tell without breeding them to the same fallow mutation they may be split for. The fallow chick well be split to rosey if it out turns out to be a boy.


Young Fallow Bourke with red eyes.

Hope that helps,

Su

Bourke parents with their young.  Rosy Bourke mother is in front.

Thank you, Su!

Peace and Blessings to All.



PUNNETT SQUARES FOR BOURKE COLORATION: Bird Genetics 101 ... Explaining it to Me.

I received a nice email from Diana challenging what I'd written in my January 4 post, "Bourke Coloration, A Question and Answer."

She gave a long and detailed explanation why I was mistaken in my calculations regarding transmission of coloration in Bourkes. To make a long story short, I’ve learned that humans and birds do not share the same genetics. Humans, other mammals, some insects and plants all follow what is known as the XY sex determination system. In this system, the male is heterozygous (XY) and the female is homozygous (XX). Thus the male determines the sex of the offspring.

Birds, it turns out, operate on a ZW system with the male being homozygous (ZZ) and the female heterozygous (ZW). So, unlike humans whose sex is determined by the father, in birds it is the mama bird that determines the sex of the offspring. However, papa determines the color since color is sex-linked to the male chromosome. Let’s hope the following clears the water.

Here is a Punnett Square for coloration of Bourke parakeets generously provided to us by Su Yin (neversink7). If you replace the rosey with lutino, it also works the same way.

My husband put the following together for me before I received Su Yin's Punnett Square. It says the same thing, but is visually different. Please consider it copyrighted as I will include it in a book on small exotic birds in the future, so don't steal or repost his illustrations. Thank you.

Quote from E.G. Lewis: "Many people use what is known as the Punnett square to predict an outcome of a particular cross or breeding experiment. Named after Reginald C. Punnett who devised the approach, it is used to determine the probability of an offspring's having a particular genotype. The Punnett square provides a visual representation of the possible combinations of one maternal allele with one paternal allele for the gene being studied in the cross. The following chart illustrates this method by simply looking at a typical mating, which we know should result in a 50-50 mix of male and female offspring.

Sex Determination

Keep three things in mind as we go forward:

First, we are discussing only the genetic relationship between the normal Bourke and the pink, or rosey, Bourke. There are other color mutations in the Bourke family and some of these appear to behave in a similar manner.

Secondly, the coloration is sex-linked — carried on the male chromosome. Therefore, while the female determines the sex of the offspring, the male chromosome determines its color. 

And, thirdly, the color genes are recessive to the normal color. However, since they’re carried on the male sex chromosome and a female only has one male chromosome; she will express the pink color if she inherits a pink male chromosome from her father. For our purposes, the male chromosome for pink color will be written as (Z_p) and the male chromosome for normal color will be written as (Z_n)

Remember also that a bird can appear normal, but actually be a split. A split results from mixed parentage and the offspring can carry one unexpressed gene for coloration. Depending upon what bird they are mated with, this color gene can be passed to their offspring resulting in what appears to be a normal parent producing pink babies. Of course, two full normal parents will only produce normal offspring and two full pink parents will only produce pink offspring. Now let’s examine possible combinations between normals, splits, and rosies. Keep in mind, all splits are normal males.

Pink Male - Normal Female

Our first sample mating is between a Pink Male and a Normal Female. In this case all of the males will be splits and all of the females will be pink.

 Normal Male - Pink Female

Next we look at a Normal Male and a Pink Female. In this case all of males will be splits and all the females will be normal.

 Split Normal Male - Pink Female

Now we’ll pair a Split Normal Male with a Pink Female. Half of both males and females will be pink. The rest of the males will be split normal whereas the other females will be normal.

 Split Normal Male - N Female

Lastly, we’ll pair a Split Normal Male with a Normal Female. Here half of the males will be normal and half will be splits. Likewise, half of the females will be pink and half will be normal."

My (Gail's) personal experience has been when combining a rosy male with a normal female, the females are always rosy and the males always normal. Further, when I combined one of their normal males with a normal female, the same pattern prevailed that all their rosies were hens and all males were normals, so he was split to rosy. I've been telling people on this blog to expect their young Bourkes to be the color of the opposite-sexed parent, unless one is split, which creates another possibility. This has proven true for me and for a friend with a lutino and a normal too. However, our small sampling is not enough to be completely correct.

Please refer to the Punnett squares above for a more accurate percentage of how your clutches may end up.

For more on genetics:  Su Yin on Bourke Genetics

Peace and Blessings,

Gail

Bourke Coloration, A Question and Answer

White faced, pink-eyed Rosy Bourkes; opaline fallow.

QUESTION:
Hello,

I have baby Bourkes this year and really enjoy them so much. I have had Bourkes for about 3 years and not had any babies til I got another pair, which have been wonderful parents. The first clutch gave me 2 beautiful normals and this present clutch gave me 4 babies that are now 2 wks old. One of them has pink eyes and looks like a pink belly and some yellow on its wings and lots of blue. They are still very young to tell, but I am wondering what it may look like. The father is a normal and the mother is a Rosy Bourke. It will be fun to find out as it grows. If you have any insight please let me know what I might be seeing.

Just love your website and have sent you emails previously about my Splendid parakeet. He is still alone, but maybe someday he will have a friend. He is such a sweetheart

Thank you for your time.

I'd call this mixed coloration a "pied" Bourke.

ANSWER:

Congratulations! And thank you for the compliment on my website.

Since color in Bourkes is sex-linked, a baby Bourke's color will come from the parent of the opposite sex. So, your Normal babies should be hens since their father is the Normal. Any Rosies will be males since their color comes through the mother.

An exception to this is the heterozygous or homozygous characteristic. I had a pair of Normal Bourkes who always produced male Normals and Rosy hens. Why, you ask? Because the male was heterozygous (his father was a Rosy and his mother a Normal). He was split to Rosy.

A Bourke that's heterozygous carries a gene for the other color, not just one color. Make sense? I still struggle with this concept.

A mated pair of Normal Bourkes. Male in back has same
colors, but brighter. Also a tiny blue ridge above cere.

So, unless a Normal male is heterozygous—and yours is not going to be since you've been getting Normal offspring from him—all your Rosies will be male because their mother is a Rosy and their father is a Normal. Your pink-eyed baby will be male.

I wish you luck with all four of them. I seem to lose more of my pink-eyed offspring as that genetic trait tends to be less strong than the dark-eyed birds. Yellow lutino's are also less strong. Healthiest of all are usually the normal, wild color. The breeding toward rosy or pink is beautiful, but less robust than their wild-colored, brown/rose/blue, ancestors.

As for the color of your one baby with pink eyes and yellow and blue feathers, there are lots of possibilities. People have been producing what they call “rainbow” Bourkes with lots of mixtures. It would be interesting to see a photo of yours when it’s fully feathered out.

This photo was sent to me. Breeder says it is a "rainbow" Bourke.

A mixed clutch of Normals and Rosies. Both parents are
Normals, but father is heterozygous and throws Rosy hens.

I’m no geneticist and asked my husband if he could explain this any better than I did. He added this:

“As with all living things, the pink color is due to genetics. We — birds and humans — have pairs of genes. We received one from our mother and one from our father. A geneticist would call an individual possessing two of the same genes for a particular trait homozygous. Homo comes from the Greek homos, meaning same. Similarly, they would refer to an individual possessing different genes for a particular trait as heterozygous…coming from the Greek héteros, meaning different.”

2011 siblings. Younger baby has red eyes.

Photo by Jill Warnick of her mixed clutch.
Lutino's are all hens since their father is a Lutino.
Mother is a Normal Bourke, so Normal baby is male.

January 18, 2013:
 

My small sampling doesn't give an accurate picture of all that is genetically possible. If you've come across this post, please also read a more accurate and easy to understand update on Bourke Coloration in the following link:

  Punnett Squares for Bourke Coloration. 

Peace and Blessings.

Avian Genetics, Bourke Parakeets by Su Yin

Introducing Su Yin who has commented on this site frequently as "neversink7," and graciously agreed to be a guest blogger on avian genetics. Below follows her post on Bourke genetics.  For your education and enjoyment! 

BOURKE GENETICS

Bourkes are a delightful grasskeet.  They are the only grasskeet with pink being their main color.  Quiet and friendly with males being excellent singers, it’s hard to resist trying to keep a pair of each mutation!  Often, there are multiple terms that are used to describe the same mutations.  I will try to include the more common ones.

Basic genetic  nomenclature:

Normal or wild color refers to the natural or baseline genetics/coloring of the birds in the wild.  Mutations alter the baseline appearance of the birds from normal/wild colors.

For birds, similar to humans, there are 2 copies of each autosomal chromosome on which the genes exist, so there are 2 copies of each gene.   There are also the sex chromosomes that determine the gender of the bird.  In contrast to humans, the male bird has 2 copies of the same sex chromosome called the Z chromosome (ZZ) and the female bird has 1 copy of the Z chromosome and 1 copy of the W chromosome.  For the mutations that exist on the Z sex chromosome, the male bird can have 2 copies of these mutation genes while the female bird can only have either 1 copy or none.

Another concept that is important to grasp is dominant or recessive.  A gene that is dominant will show up even if only 1 copy of the gene exists in the bird.  If a gene is recessive, there needs to be 2 copies of the mutation gene in the bird in order for the mutation to show up. 

The term “split” applies to the recessive genes when the bird only has one copy of the mutation gene.  Since it doesn’t have 2 copies of the recessive gene, it will not physically show the mutation, but it carries the hidden mutation gene that can still be passed to its offspring.

Common bourke mutations:

Note Normal male at left has brighter colors
than Normal hen on right. © Gail Lewis

Normal: 

The normal Bourke is subtly colorful with grey over the head and back, dusty pink on the belly, yellow scalloping on the black wing feathers.  The males have blue across the brow and the hens do not. Males also have more blue on their wings.

Autosomal recessive mutations:

The genes for these mutations are on the autosomal chromosomes and 2 copies of the mutation gene are required to physically show the mutation.  Both the male and female can be split to these mutations.

Bronze fallow male:        ©Su Yin

Bronze fallow: 

All black pigments are changed to brown shades, eyes are red, skin and nails are pale. The bird generally looks lighter.  The blue band on the brown and wing still exists in the male and not in the hens.  There can be different degrees of darker vs. lighter coloring depending on the strain.

Pale fallow:

Pale fallow male: ©Su Yin

Also called cream or yellow.  All black pigment is changed into light browns, eyes are red, skin and nails are pale.  The color overall is lighter than bronze fallow with more yellow/cream colors.  There can be different degrees of darker vs. lighter coloring depending on the strain.

Pale fallow hen: ©Su Yin

 Photo by Atholl Shelton (Australia).
http://grassparrots.free.fr/bourkes'p/pied%20%20025_jpg_view.htm.

Pied: 

Irregular pattern of absence of deposition of pigment all over the body.

Sex-linked recessive mutations:

These mutations are genes that only exist on the Z chromosome and require 2 copies of the mutation gene in males but only need 1 copy in the females to show up physically.  Since the hens only have 1 copy of the Z chromosome, they will either show or not show the mutation, whereas the males can be split to the mutation if they have only 1 copy of the mutation gene.

Cinnamon:

The black coloring is brownish colored.  Eyes are dark red.  Nails are horn colored.  No increase in the yellow or cream coloring.

Cinnamon Bourke:
http://bourkenaround.files.wordpress.com/2011/04/dsc02597-copy1.jpg.

Lutino Bourke     ©Su Yin

Lutino:

Inability to produce any dark pigment, so normally blue areas are white, pale pink over the head and body with yellow coloring over the wings and back.  Skin and nails are very pale.  Eyes are light red.  Males may be a little darker in color, but confirmation of gender requires behavioral differences or DNA sexing.

Opaline males: ©Su Yin

Opaline:

More commonly known as rosy or rosa.  This mutation mainly redistributes the existing colors of the Bourke but enhances the pink/red colors.  Thus the common name of rosy because most birds with this mutation look pink all over.  Some birds can have blue or green in the tail region. 

Through selective breeding, strains of mostly blue or green and other variants have been developed.  These are not different mutations from the opaline, just variations of the same mutation through selective breeding.   Those with a little bit of every color are often called “rainbow.”  Males usually are darker in color while less black/grey on the face, but this is not 100% reliable.  Both genders will have the white stripe on the underside of the wings, which usually only shows up in hens. 

Below are examples of opalines with less pink and other colors. To the left is a blue opaline and the one on right is often called a rainbow.

Blue opaline Bourke.
Breeding and photo from A. Coljon.

http://grassparrots.free.fr/bourkes'p/Coljon%20Blue%202010%20cd_jpg_view.htm.

http://grassparrots.free.fr/bourkes'p/YB%20Coljon%20B0015_jpg_view.htm.

Rainbow Bourke.
Photo and bred by A. Coljon.

Combinations of mutations:

When different mutations are bred together, one can develop combinations of the different features.  Included here are only the more commonly available combinations, but let your imagination run wild with the endless possibilities J.

Opaline fallow:

Often called pink, sometimes white-faced pink. These can be developed with combination of the opaline and either the bronze or pale fallow mutations. There is a lot less of the black/darker pigments and eyes are red. Again, males may be darker in their red/pink color with the hens having more white on the face, but this is not confirmation of gender.

Pink hen or opaline fallow hen:        ©Su Yin

Pink male or opaline fallow:       ©Su Yin

Opaline lutino:

More commonly known as rubino.  This is a combination of the opaline and lutino mutations.  The birds are still red eyed with complete lack of darker pigments.  The addition of the opaline gene redistributes the red/pink pigments to a wider area of the body, so the birds tend to be darker pink than lutinos with more pink on their back and wings.  Gender can be very difficult to tell based on appearance alone.

Opaline lutino:          ©Su Yin

A little about me… (Su Yin)

I’ve been a lifelong lover of animals and nature.  I’ve kept different mammals, namely cats and most recently a dog, though I have dabbled in bunnies and mice in the past.  Then there is some venturing into reptiles and frogs, but birds have definitely developed into a passion for me. 

I started with a pair of zebras and now have numerous birds of several species.  I keep various finches and breed some of them.  Gouldians and societies make up the core of my breeding program, but I do also breed stars, owls, shaft tails, and various parrot finches at times.  I also try to breed some of the rarer and very difficult to breed waxbills, but that’s another very long story J. 

I started keeping grasskeets a few years ago.  Once I saw a picture of a scarlet-chested grasskeet, I just had to have a pair.  From there, I acquired turquoisines.  I managed to resist Bourkes until I chanced upon The Splendid Bourke Bird Blog, then saw one in person, and I was hooked.  Recently, I’ve also acquired a couple pairs of elegants.  Just like finches, different species of grasskeets have different personalities, but most are peaceful and make good neighbors for the finches I keep together with them. 

Having a background in the biosciences, I naturally gravitated to the interesting genetics that birds can have and love the challenge of trying to breed quality birds as well as different mutations.  There are books available for reference on the different mutations of various birds, but a lot of information can often be found online – try googling  ;D.  Feel free to check out my birds at:

http://happybirdplacefinchandgrasskeetblog.blogspot.com/