1. Institute of Natural Resources, Ecology Group, Massey University, PO Box 11222, Palmerston North, New Zealand
2. Institute of Veterinary, Animal and Biomedical Sciences, Massey University, PO Box 11222, Palmerston North, New Zealand
3. NZCCM, Auckland Zoo, Private Bag, Grey Lynn, Auckland, New Zealand
4. Institute of Natural Sciences, Massey University, Private Bag 102 904, North Shore Mail Centre, Auckland, New Zealand
5. Institute of Environmental Science and Research Ltd., PO Box 50-348, Porirua, New Zealand