I have seen considerable numbers of magpies in NZ farm land. NZ Birds Online says they are ‘a common and conspicuous inhabitant of open country’. In my original post I did say that the belief that they are a threat to native species is ‘possibly incorrect’.
But they are widely so regarded. I had friends with a farm near Waikato. The Waikato Council makes landowners responsible for the control of magpies on their property and suggests a combination of trapping, shooting and poisonong to eradicate them.
John
No serious evidence of that in NZ, In my experience Magpies in NZ can be found in not great numbers in open agricultural districts in the North island, they are fairly wary and they don't have a great 'press' with the locals. The abundant Swamp Harrier is
probably a greater threat to other birds in open country. You never see magpies in native forests, where most of the native birds survive. You do find Indian mynas, European blackbirds, Chaffinches and Eastern Rosellas in such places though. Where there
is active stoat and possum control, as Nathanaeal below says, there is an amazing rebound in the fortunes of NZ native birds. I know forests in the Central north Island that are alive with the otherworldly calls of the local birds as a result.
David.