Kevin Eatwell BV.Sc.(hons) MRCVS of F, S and K Eatwell
Crested budgerigars have always been a variety that is in short supply. They are not the easiest to breed in large numbers due to complicated genetics. The quality of many of the specimens is poor. They have never taken off as a popular exhibition variety for both these reasons.
When I started with this variety in 1987, the initial quality of the birds acquired were poor. When breeding with crests two things need to be considered the same as any specialist variety.
Firstly you need to produce sufficient numbers to be able to select a breeding team for the next season and you need to aim to improve the exhibition quality of the birds you keep.
In any other variety the genetics are well known and a set pairing will produce a certain percentage of birds that are of the variety that is desired over time. With the crested any pair can produce any number of visual crested or crestbred (non-visual birds). It is this unknown quantity which makes life harder. On top of this the quality of the crest is also important, but I feel we as the breeders can do little to control its visual appearance.
There are three types of crest recognised but this is far too simplified. The crests can vary from one disturbed pin feather whilst in the nest, to a bird with three circular crests on it's head with other disturbed feathers down it's back and occasionally elsewhere. I recognise 15 different crest combinations in our stock; only, a percentage of which fit a category laid down by the Budgerigar Society.
1
Three circular crests on the head additional distorted feathers down the back
2
Frilled crests:
Three circular crests on the head additional distorted feathers down the back
3
Double full circular crests:
Two circular crests on the head additional distorted feathers down the back
4
Full circular crests:
One circular crest on the head additional distorted feathers down the back
5
Half circular crests:
A semicircular crest on the head, rather like a wide tuft
6
Tufted crests:
A cockatiel style crest on the front of the head
7
Small tufted crests:
A few raised distorted feathers still quite visible
8
Special crestbreds:
Distorted feathers at the back of the head, noticeable as a week old chick, some may appear non-crested later in life as they grow (so record it on the records at this time!)
9
Crestbreds:
Have appeared normal form day one
10
Non crested (normals)
No crested blood in the recent history
There are essentially three useful pairings that can be made when aiming to breed crested budgerigars: -
The general rule is the more distorted feathers the bird has the greater percentage of crested birds it is likely to produce. The aim with our crests is to generate sufficient numbers for selection each year. Many breeders go for the improvement in the variety far to quickly. A number of excellent birds can be produced in this way, but it is noticeable how a number of prominent fanciers no longer have birds related to the original stock. I presume this is due to poor fertility and lack of visual crests produced. Producing large numbers of crests ensures enough to select for the next season but will not increase the exhibition quality that fast and will lead to inbreeding to a higher degree than liked. When breeding a crested stud the aim is to hit the happy medium between these two. I aim to produce about 25 - 30 visual chicks per year with about 30 - 60 crestbred being produced alongside these. In order to achieve this ratio the number of outcrosses used are fewer than I would like and so any crestbred generated from a crest to a crestbred are sold unless of good quality. A number of crest to crest pairings are made (generally tuft to tuft) to produce frilled crests (a bird with multiple crests on it's head) suitable to outcross to non crests. These have a high chance of breeding visual crests from such a mating. Even producing 30 visual crests does not give much of a number to select from, about 35 visuals being retained each year from these and the adults. Progress is slow, but it needs to be, to keep producing visuals and maintaining fertility. I do feel that the crested variety is one of the few specialist varieties that can give good justification for remaining smaller than the other exhibition budgerigars.
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