NZ's 2nd rarest native parrot increasing on BP

[Tomtit24]

Well that's great news on the Tui front! And I hope I live to see the day when kaka and Cockatoos wheel about the valleys of BP!

[Jim_j]

Andrew I'm pretty sure no studies have been done (which I'm sure you are aware).
As far as I know the only place that Kaka and S/C are found together (in very small numbers for both) is the Waitakeres in Auckland.
So nobody can say what impacts there might be for sure as there are not enough of either species - let alone interactions to do any studies.
The only comment I've seen is an anecdotal report (on this site I think) - that they ignored each other.

All I'm suggesting is that there may be a potential impacts (the obvious one I can think of is competition for nest sites) so any exotic animal that makes it here - either by "natural" means or human assistance may impact the recovery ofa relict native species.

I agree that multiple species of parrot co-exist in Oz so it would be a reasonable assumption that the same might happen here - but if you look at the history of exotic species in NZ - what people thought would happen and what has actually happened can be quite different.

I guess it also depends on your point of view - if you are happy to have endemics confined to areas of "natural" vegetation - with modified areas open slather then it probably doesn't matter if they impact on kaka or not.
Either species of course is probably not going to be welcomed by orchard owners!

cheers
jim

[Neil Fitzgerald]

.. could someone knowledgeable and citing evidence rather than supposition please give examples of where cockatoos have put pressure on kaka to date?

Ditto on that from me too.

[andrewcrossland]

I guess my view is based on cockatoos being one of Australia's most successful export species, there being almost as many varieties of SC cockatoos and other so of cockatoo than there are models of holden. My view is also based on the assumption that the banks peninsula population at least is the progeny of bonefide free flying trans Tasman colonists rather than birds brought here by human agency. That may be wrong, but for arguments sake, if it's right, then the cockatoos are a native it'd following the westerly flow of new species into nz and therefore we kinda have to make a bit if room for them and suck it and see.

[SomesBirder]

I have a good feeling that even if there was evidence which gave reason to believe that cockatoos are not a threat to kaka, this would have no impact on how councils and conservationists treat them. After all, that is what happened to magpies; research showed that their impact on native birds is negligible, and yet regional councils throughout the country still consider them a major pest.

[Jim_j]

Mmmm - Neil that logic has worked really well for us hasn't it?
Plenty of stoats & rats & weasels in the UK - haven't caused any birds to become extinct there - must be ok in NZ.

In fact that's pretty much how we seem to work - wait for the science to catch up
Course lead in paint is alright, cause smoking tobacco wont hurt you, course you can burn fossil fuels with no impacts, course you can keep adding nitrogen to pastures.... the problem is that it can take years for the impacts to be known.

I know exaggerating for effect - and I'd like to see s/cockatoo around as much as anyone - but- there are plenty in Oz and not that many kaka left here and if it came to a choice I'd go to Oz to see them and just have kaka here any day.

cheers
jim

[Jan]

Jim, you don't live near Banks Peninsula, I guess, and there haven't been Kaka there for a long time. While this isn't necessarily a valid point, people that do live near Banks Peninsula [and especially in the valley where most of the S-C Cockatoos hang out] really like them and don't mind having them around. It would be a different matter if they were out-competing Kaka, but there doesn't seem any likelihood of that happening for a very long time. I suppose I'm saying please give us our foibles, nicely?

[Neil Fitzgerald]

Actually Jim, I think evidence-based decision making has worked really well for us. The problem is so little of it happens in this country, especially when politicians get involved.
I have seen lots of science done on causes of kaka decline, and not once has cockatoo competition come up. Stoats, lead poisoning, food limitations. Those are things that do come up. Cockatoos show no sign of getting out of control in the near future, and kaka appear to be doing ok where they coexist, so I'd worry about the big problems staring us in the face first.
If that evidence turns up though, then I'll gladly change my stance.

[Ian Southey]

By and large people just don't well enough to say, especially for really solid evidence based decisions but I presume you're thinking about things like nest holes and food and not something like beak and feather disease? 50/50 chance it was cockatoos, the only other candidates are the rosellas.

Ian

[Neil Fitzgerald]

I don't know the full b&f disease story. The little I have heard is that at least some of it is probably endemic, so ethically we should probably be protecting that too. Has it actually been the cause of decline in any wild populations?