Bourke's Parrot (Neopsephotus bourkii)
Breeding colour varieties of the Bourke's Parakeet: The Bourke is very interesting for bird fanciers, not only for the beginner, but also for the advanced mutation breeder. The Bourke is the only brown grass-parakeet in Australia. He is often surprising the bird fancier because he is so different from the green parakeets, like the Neophema, in behaviour, but also in his colour qualities.
A separate genus: The Bourke has to be seen as a separate genus. This point of view is fruitful to get insight into the peculiar colour varieties of the Bourke. The scientific name is Neopsephotus Bourkii. Neo (Greek) = new, Psephotus (Greek) = "inlaid with pebbles". This is a nice reference to the colour pattern of the wings with the little brown coverts, with white margins. The Bourke is not a member of the Neophema family. Mating with Neophema is not possible. There are no hybrids of the Bourke. All the colour varieties of the Bourke are pure.
Many of the colour mutations of the Bourke's took place in aviaries of bird fanciers in Holland. I was spectator and participant in the developing of new colour varieties for more than thirty years. To become a more comprehensive view of the Bourke mutations, I have developed a new concept for naming, description, classification, and predicting colour varieties of the Bourke's parakeet. My intention is to present every month some new pages. I make a start with the wildtype Bourke because every new colour variety is dependent on the colouring elements of the wildtype.
The Bourke is very peculiar, the wildtype Bourke has a dull brown plumage like the house sparrow. You do not expect red, yellow, blue and green varieties of a sparrow. But the brown Bourke is surprising us with several, beautiful, possibilities of colour and colour combinations.
It is possible now to breed the Bourke's parakeet in different colour series. In the sixties and seventies light brown, yellow and rose colour varieties are developed. But in the last years also unexpected colours, like white, blue and green, did appear.
This collage shows pictures of colour varieties in five different colour series: blue opaline (B-5), red opaline (R-5), green opaline pastel (G-53), green opaline young (G-5),yellow pastel (Y-3),. white opaline-pastel (W-53). With a click at the links you can see a blow up of the picture and a description of the colour variety. Later in this site I shall present the pictures with descriptions and information about development, inheritance etc.
1. The wild type Bourke
When a fancier is interested in breeding colour varieties he has to start with knowledge of the wildtype. Every mutation means change of the colour formation of pigments and feather structure. Every bird species has his own unique combination of genetic qualities.The breeder has to know the characteristics of the wildtype Bourke, the colouring of his plumage, horny parts and eyes. Also some background knowledge about genetics is needed. The Bourke is a very interesting species because he has special qualities compared with other parrots.
2. Using clear concepts
A lot of breeders and even writers are using the expression:"mutations" when they speak about mutation factors or the new appearance. This causes a lot of confusing because mutation, mutation factor and colour variety are three different concepts.
A mutation is a spontaneous change of a gene in the process of cell division. A mutation is a distortion in the process of copying the DNA. It is an invisible, spontaneous incident. The result is an altered gene. A colour variety is a new appearance of the species. A colour variety is based upon a mutation factor (the changed gene) in combination with the original (not changed) genes of the species. A colour variety is a new phenotype. A mutation factor is an altered gene. The sum of all genetic qualities is the genotype of the species.
An important starting point is use clear concepts, use jargon as little as possible and give an explanation when using scientific terms is inevitable.
3. Using common and scientific names in the aviculture
There are two types of names for bird species and varieties of bird species: Common of local names and scientific names.The common name is based upon the altered appearance of the species. The scientific name is based upon the altered genetical make-up of the species.
The common name is a descriptive name. Description of the visible characteristics. The common names of varieties are most given by the breeder, who was developing the new colour variety. Many common names of birds and varieties are colour names. The common name of a variety is typifying the colour variety, compared with the wildtype or other varieties of the same bird species. It is a name given in the mother language.The name refers to the phenotype of the variety
The scientific name should be an explanatory name. This name explains the causes of the change of formation processes of pigments or the feather structure. The scientific name has to be based on research. The scientific name is given in science language. Long ago this was: Latin or Greek. Today it is: English. Each of them, common names and scientific names, are serving there own purposes. The common name serves the national or local communication. The scientific name serves international communication. The name refers to the genotype of the variety
4. A new scientific method for developing scientific names of varieties
4.1. Taylor (1961) and his followers used a traditional scientific method that has to be used when a gene is known only by the mutant phenotype This name refers to the appearance. In this method common names and scientific names are equal. This traditional scientific name giving has several limitations. The names are not developed systematic. The names are common names, local names. Most of them are colour names. This kind of name giving cannot fulfil scientific aims. The names for parrot varieties are borrowed from the Budgerigar. Taking this species as a model gives problems with the name giving of varieties of bird species who do not have the same genetic qualities. Outside of the Psitticaformes and inside of this Order, like some Cockatoos, Bourke's and Cockatiel This method falls short in systematic classification of parallel mutations and other scientific goals. Even communication is problematic.
4.2. In this publication a new scientific method, the trinomial system is used. The name should be related to the cause of altering of colour producing pigments and feather structure. This method is based on research findings described in the constantly growing knowledge of colour formation processes. This system can be used for varieties of all kind of bird species. It is suited for all scientific goals like classification of parallel mutations, etc. It is not restricted to one bird species, genus, family or order. It is suitable for communication.
4.3. Using the trinomial system. Behind the binomial scientific name of a species (Greek or Latin) the abbreviation of the English name for the mutation factor is placed (in between parenthesis). Example: The scientific name of the Bourke species is : "Neopsephotus bourkii" The scientific name of the lutino Bourke, one of the colour varieties of the Bourke, is: "Neopsephotus bourkii (M-t+)" The third part of the name looks like a letter code. If the variety is due to more than one mutation factor, the letter code is extended. The scientific name of the opaline-fallow variety is: Neopsephotus bourkii (M-di, M-a) Because there is a rather restricted number of mutation factors (about 30) ithe whole sysystem is easey to manage. easy to manage. I developed a survey of all codes.
5. Classification of all Bourke varieties
5.1. The colouring elements of Bourke and Budgerigar are different. The Bourke belongs to a monotypic genus. The plumage of the Bourke is coloured by pigments and feather structure. The Bourke has brown eumelanin pigment, red and yellow psittacine pigments, and a restricted amount of feather fields with feathers of the structural type. In each of this pigments and structure distortion and change can take place. All changes in the distinct formation processes influence the colours of the plumage.
5.2. I developed a matrix with two entrances: In the first vertical column the changes in the melanin formation (M), in the first row the changes of pigments (P) and feather structure (S). Every colour variety colour variety can be placed in this matrix according to the reference colour and the formation distortions of pigments and structure. On of the profits of a classification matrix is the possibility to predict new varieties and even new mutation factor of a bird species.
PS M-factors are the most important colouring qualities of birds, because all birds (brown and multi coloured birds) have this pigment.
6. Classification model for parallel mutations in parrots and other bird species
A classification of all known mutation factors in parrots is developed on the base of the work of Steiner one of the most important forerunners of research and systematic development of parrot varieties. The classification can be extended easily when new mutations arrive. The classification is not restricted to one species or order of bird species but is in principle to use for all mutation factors in all species.
7. Presentation of important resources for breeding resources
Presenting information about wildtype and varieties, pictures of all known varieties, cross tables for mating and prediction about outcomes in an new easy to use presentation, check lists about quality management, case studies, and back ground knowledge about genetics. Together is forms a complete survey of all aspects of breeding Bourke's colour varieties.
Most of this starting points are really new and are a try out for renewing the body of knowledge and practice of bird breeding in general and breeding the Bourke's species in particular. This publication is developed in three year, as a web site about Bourke's, based on more than thirty years of bird breeding and usable study. My devise is that practice and studying should go hand in hand. Breeding varieties is one of the most interesting hobby's I know. I am grateful for so many spontaneous, positive, encouraging mails I got of visitors of my website.