A very interesting study...considering our breeding of captive kakariki, very limited generic source...and taken along with discussions with leading kakariki breeders in Australia a Europe.
IT significantly substantiates much of what experienced amateur kakariki breeders have known for decades, but it only touches the tip of the iceberg of inbreeding....The big advantage in he wild is 'defective' birds often die..in captivity there tends to be a very marked drop off in quality size, fertility and gentic traits of kidney, spinal, vision, and length of life. Due to some breeders 'keeping' a bird that has a positive trait, along with a bad. These good and bad traits are considered as mutations, and can be pasted onto future generations and being in captivity survive, when if in the wild they wouldnt.
Bad traits from in breeding in captivity, not only are the siblings culled but the parents to prevent these 'mutations ' in future generations.
This is often seen in show pedigree lines of some breeds of dogs, week spines, hear and kidney issues.
The paper also mentions introduction of blood lines from sub species...
Experimentation breeding between a yellow and red kakariki, they will not interbreed if their are others of its species around... to do so requires forced breeding beyond a couple birds in a small flight....isolation and very small breeding cage...such conditions do not exist in the wild...
The paper also briefly looks at the song being an issue of choice of pairing, there has been some research on several grass parrots, these have a ulta violet (seen in the birds spectrum of vision) on the tops of the crown. the shape , intensity of the patch is a large factor in determining choice of pairing. We have not established if kakariki also have such a patch.
When a colony of kakariki are in a flight, siblings, adults....natural pairing off is very rare between closely related birds, and pecking order also has a strong influence.
With small populations of many NZ species, one wonders how many of the natural mutations have been lost...
Kakariki where of special interest in the 1800s due to a very high incidence of several natural colour mutations...great effort was made to capture and export these, and along with easy mass destruction by early settlers of kakariki, then increased rat, vermin population, what was left had/has lost the natural colour mutation genes, as has our captive population. of the captive population in NZ I know of 4 kakariki that show any mutations.... 1 is to old to breed, the others are of breeding age, but have yet to breed due to difficulties in getting them to pair to distant related or inbreed.
The paper is good, but some of the conclusions are made on assumptions, need further investigation to confirm recommendations or discard. In corporating studies of species held under schedule 3 of the Wildlife Act 1953 in captivity.
Of point is the recommendation not to introduce lines from other isolated colonies....wher once the species was common thru out NZ, as in the case of Red , Yellow, Orange kakariki, there was a continuous crossing of borders, creating a fairly uniform genetic diveristy... not to draw from these I believe would be a mistake that very well could come back and kick us in the butt.
Not only should we be introducing where possible new blood into our wild and captive stocks from wider areas, but importing lost genetic lines from captive stock in Australia, Europe and America...Doing so is going to be the only way to return the NZ stocks back to some resemblance of 150 yrs ago.
