1 WALKER ET AL.: HALTING INDIGENOUS BIODIVERSITY DECLINE New Zealand Journal of Ecology (2008) 32(2): 0-0 ©New Zealand Ecological Society Available on-line at: http://www.newzealandecology.org/nzje/ FORUM ARTICLE Halting indigenous biodiversity decline: ambiguity, equity, and outcomes in RMA assessment of signifcance Susan Walker 1* , Ann L. Brower 2 , Bruce D. Clarkson 3 , William G. Lee 1 Shona C. Myers 4 , William B. Shaw 5 , and R.T. Theo Stephens 6 1 Landcare Research, Private Bag 1930, Dunedin 9054, New Zealand 2 Environment, Society, and Design Division, PO Box 84, Lincoln University, Lincoln 7647, Canterbury, New Zealand 3 Department of Biological Sciences, Science & Engineering, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand 4 Auckland Regional Council, Private Bag 92 012, Auckland 1142, New Zealand 5 Wildland Consultants, PO Box 7137, Te Ngae, Rotorua 3010, New Zealand 6 Research, Development and Improvement Division, Department of Conservation, Private Bag 1930, Dunedin 9054, New Zealand *Author for correspondence (Email: walkers@landcareresearch.co.nz) Published on-line: 27 August 2008 ___________________________________________________________________________________________________________________________________ Abstract: In New Zealand, assessment of ‘signifcance’ is undertaken to give effect to a legal requirement for local authorities to provide for protection of signifcant sites under the Resource Management Act (1991). The ambiguity of the statute enables different interests to defne signifcance according to their goals: vested interests (developers), local authorities, and non-vested interests in pursuit of protection of environmental public goods may advance different defnitions. We examine two sets of criteria used for assessment of signifcance for biological diversity under the Act. Criteria adapted from the 1980s Protected Natural Areas Programme are inadequate to achieve the maintenance of biological diversity if ranking is used to identify only highest priority sites. Norton and Roper-Lindsay (2004) propose a narrow defnition of signifcance, and criteria that identify only a few high-quality sites as signifcant. Both sets are likely to serve the interests of developers and local authorities, but place the penalty of uncertainty on non-vested interests seeking to maintain biological diversity, and are likely to exacerbate the decline of biological diversity and the loss of landscape-scale processes required for its persistence. When adopting criteria for assessment of signifcance, we suggest local authorities should consider whose interests are served by different criteria sets, and who will bear the penalty of uncertainty regarding biological diversity outcomes. They should also ask whether signifcance criteria are adequate, and suffciently robust to the uncertainty inherent in the assessment of natural values, to halt the decline of indigenous biological diversity. ___________________________________________________________________________________________________________________________________ Keywords: collective action; conservation evaluation; interests; precautionary principle; representativeness; uncertainty Introduction Signifcance assessment in the RMA In New Zealand, the Resource Management Act (1991) (hereafter RMA) is the major statute for agency-based decision-makers determining whether indigenous habitats and ecosystems on private land may be cleared or protected against harm. Assessment of ‘signifcance’ is central to this determination. Agencies with statutory functions under the Act are required by Section 6(c), as a matter ‘of national importance’, to recognise and provide for the protection of ‘areas of signifcant indigenous vegetation and signifcant habitats of indigenous fauna’. This responsibility is assigned to local authorities (territorial authorities, regional councils and unitary authorities), who must provide for the protection of signifcant areas in their districts or regions. Section 6(c) is not the only part of the RMA relating to the maintenance and protection of indigenous biological diversity (see for example §5(2)(b), §7(d), §30, and §31) but is particularly important because