[I see no evidence presented that it is the lorikeets that keep out the native birds. Birds like turquoise and ground parrot are species of grasslands. Grassland that has been replaced by urban landscapes.

Presenting these ideas as facts and pointing to the lorikeets as scapegoats is highly unscientific--]

As to this comment by Roelant, it is wrong that lorikeets do not affect grassland and other smaller birds. The Swainsons’ where they have moved in, compete with parakeets for nesting sites--witness the problems in Western Australia where introduced lorikeets are the more aggressive species and will belligerently move Regent Parakeets (Rock Peplers) out of nest cavities making it more difficult for the gentler Polytelis to lay and raise young. It would not surprise me to see a rainbow pair fight with larger parrots to secure a necessary nesting site--they are that macho! Smaller birds have no chance. Of course hoodeds and some others choose termite mounds for nesting so at present lorikeets do not usurp those nests, but who knows, the lorikeets may someday learn that ruse also

Dear Yellowfronts, (got a real name btw?)

This might all be very logical in you mind. But is it substantiated somewhere in scientific literature? Would like to read it.

http://www.nationalparks.nsw.gov.au/PDFs/tsprofile_regent_parrot.pdf this article does not mention non native lorikeets as a threat.

The argument of nest competition has been brought up again and again in dealing with non native parrots. Nowhere did I see convincing evidence.

Let me know if you find anything.

Roelant--

I just spent half hour trying to find the article in Australian Birdkeeper about threatened Regent Parrots being in competition with introduced Swainsons in Western Australia.
I finally figured I don’t have time to be going back in my archives to find the “scientific proof” you want in order to convince your doubts about the posting....

So I googled “Regent Parrot competition with lorikeets for nesting” and got ten pages of articles, reports and field notes. I suggest you do the same. There is a wealth of information.

Some of the quotes I discovered: 

“The lorikeets also exclude native birds from feeding resources and nesting sites, kill the nestlings of other bird species, and carry Psittacine beak and feather disease in the liver (once infected) which they can spread to native lorikeets and other parrots.”

“Lorikeets will fly onto a food supply in a group and chase the native birds away. Lorikeets can chase larger birds away like the sulfur crested cockatoos.”

“In Perth rainbow lorikeets cause a number of problems including.... competition with other species for food and nest sites.”