Don't ignore the fact that mutations happen in
wild stocks, just as much as in domestic stocks especially in the long term.
Wild stocks are not "pure" anyway. This is the stuff of evolutionary
process. The only difference is that people often select things differently to
nature. A new colour variety appearing in domestic stock (if it looks nice) will
usually be propagated into a new variety. Oddly coloured new types in wild birds
(especially flocking things like budgerigars and cockatiels in a land full of
falcons) are likely to be at a disadvantage.
There are any number of examples of oddities in
nature. "The odd blue budgerigar in flocks of
budgies in western NSW" could be a natural occurrence. As for escaped or
released birds, it is more likely to be the reduced fear, poor flying ability,
poor knowledge of the unconstrained environment and poor food-finding skills
that will be their downfall, rather than the fact that they are oddly coloured.
Release of these birds is hardly ever likely to be of concern (unless wild
populations are swamped by new varieties) as the genetic variants occurring in
captivity probably do or inevitably will have at some stage in the distant past
occurred or in the future will occur naturally anyway.
I'm not sure what is meant by "sufficiently recessive". Genes are
either recessive or they are not. The only difference is
that recessive requires that both, rather than just one allele, be of that
type for the character to show (for single gene characters and all other things
Max O'Sullivan <>
Thursday, 19 October 2000 18:47
Subject: [BIRDING-AUS] Bird
The talk of escaped Cockatiels and whether
they are cage-developed mutations raises the question about the possible
dangers of such mutations if they succeed in breeding with native stock.
How does this affect the gene pool of the
wild birds and does the mutation eventually disappear with little or no
"visible" damage to the native birds?
In other words, is the mutation sufficiently
recessive for it not to affect the purity of the native stock in the long
I have seen the odd blue budgerigar in
flocks of budgies in western NSW and was assured that they would have no
effect on the basic green native form even if they managed to avoid
predators and breed.
With so much emphasis in one area of
aviculture into mutations of all finch and parrot species, I often wonder
what would happen if a collection Cockatiel mutated birds were set loose in
an area where they could mix with a flock of native birds and interbreed -
that's assuming they could survive in the wild.