1. School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington 6140, New Zealand
2. Bio-Protection Research Centre, Lincoln University, PO Box 84, Canterbury 7647, New Zealand
3. Department of Conservation, PO Box 10420, Wellington 6143, New Zealand
4. School of Biological Sciences, University of Auckland, Private Bag 92019 Auckland 1142, New Zealand
5. Scion, Forestry Rd, PO Box 29237, Christchurch 8041, New Zealand
6. Landcare Research, Private Bag 92170, Auckland 1142, New Zealand
7. Landcare Research, Private Bag 3127, Hamilton 3240, New Zealand