Control rodents with Weka?

[Steptoe]

What effect does a substantual weka population have on rats mice stoats and ferrets?
I have been reading old settler notes where they independantly comment on how rats and mice dont enter a wekas terrotitory....a weka will hunt and kill rats and mice.
Stoats and ferrits will not take on an adult weka, and tend to move out of weka terrtory.

ALso pre hurriance bola...I have no idea if bola was an influence or not, just around that time....weka where quite common aroud the nth island...enough to be a pain...could not put anything shiney down around the camp fire (campfire, yes im going back a few decades here) without a damn weka pinching it.
It seems weka has damn near disappearted since this time and a huge drop off in bird life from since then....including other preditor birds in the forest like the morepork.

I do wonder how much could becontolled by native preditors if they where reintoduced in mass numbers ...in established floks with established pairs, and social order, pecking order and social defence mechanisms in place.....
I do believe , from my own oberservations in my captive kakariki flocks, that reintroducing birds back in small isolated numbers, with no social order, makes them very prone to preditors......but release pre established flocks of 50 or even 100 birds at a time, not only allows greater survival rates, but in the case of weka move much of the vermin from the area.

I believe many think because many of our species are terroritial...like kakariki...they are not flock birds....kakariki yes will defend the area around their nests to the end....but move just outside that area and hey become very socially interactive...so much so that checks get weaned off not by the male parent, but by single males around.   And the Alpha male stands gaurd over everything....with senturies....an increadiable warning system over very large areas.

Dont get the wrong idea..I am not anti  1080  and pioson maintance programs but do believe from my own observations and reading there are further area that should be explored.
I think it was Otrohongs park that recorded a mas drop in a rat/mice problem after they introduced the weka.

[Dave Houston]

There is plenty of evidence of weka taking rats and mice, however their ability to control populations of rodents is negligible.  The Chatham Islands have a large (10,000?) weka population and also a robust rat population (all 3 spp).  Similarly on Pitt Island there is a high abundance of mice but weka numbers are lower than on Chatham island.  Weka density does not appear to be influenced by rodent abundance but rather by habitat factors, the sandy dune and scrubby farmland country having markedly higher weka density than forest.

Climate does impact weka and while cyclone Bola may have had an impact, droughts definitely seem to have an adverse impact on weka productivity and survival, possibly reducing the availability of invertebrates.

Stoats and ferrets do kill weka  - the success of weka translocations in the South Island have affected by mustelid predation. 

Chucking a bunch of predators into the ecosystem can (and usually does) have intended consequences - stoats and ferrets are good examples.  Weka are well known predators of native invertebrates, skinks and ground-nesting birds (everything from yellow-eyed penguin eggs to adult petrels) so one has to be cautious about where to release them.

Lastly, unlike kakariki, predatory birds don't flock.  You can't apply the caged kakariki concept to the rest of the world.

[Steptoe]

Lastly, unlike kakariki, predatory birds don't flock.  You can't apply the caged kakariki concept to the rest of the world.

I think the piont was missed ...Rather than releasing a couple birds here and there....release lots of birds (flock being plural rather than  a flock) and even thu preditory birds dont flock , they still have a social sructure, inter action and communication established....

And interesting on the rest....

Thu I did not say Bola had an effect but rather about that time and dont know if it did have an effect....may well have been 22 calibre and supresser...

What age where the weka that got killed by the ferrets/stoats?  the old notes diaries I had read commented Adult birds would kill but younger where prone.

[Bruce McKinlay]

Stoats and ferrits will not take on an adult weka, and tend to move out of weka terrtory. 

On Te Peka Karara (an island in Lake Wanaka) we had a stoat arrive and rapidly predate on weka that were present there of all sizes and ages.

Bruce