Wetland management in New Zealand: Are current approaches and policies sustaining wetland ecosystems in agricultural landscapes?

Abstract

As a signatory to the Convention on Biological Diversity and to the Ramsar Convention on Wetlands, New Zealand has international responsibilities to protect and restore wetland ecosystems. The New Zealand Biodiversity Strategy also reflects New Zealand's commitment to help stem the loss of biodiversity worldwide, including wetlands. Wetland loss in New Zealand has been more significant than in most parts of the world, and ecosystems in fertile lowlands have been most severely impacted by agricultural development. Wetlands provide important ecosystem services filtering nutrients and controlling floodwaters but they are under continued pressure from agricultural land use, including drainage, grazing, nutrient runoff, and the impacts of pest animals and plants. Legislation in New Zealand identifies the protection of wetlands as a matter of national importance, and the protection of wetlands on private land has been identified as a national priority for action. While most of the larger nationally and internationally significant wetlands in New Zealand are in public ownership, the vast majority of smaller wetlands, which contribute to the full diversity of lowland ecosystems in New Zealand, are on private land in agricultural landscapes. Regional and district councils have responsibilities to implement legislation and develop policies and regulations to protect wetlands and prevent their damage and degradation. Most use a mix of regulatory mechanisms and voluntary incentives to encourage protection and restoration of wetlands. The strength of regulation for wetland protection varies across the country, with stronger more restrictive rules in more populated regions and where loss in extent has been more significant. While all regional plans have some form of rule restricting damaging activities in wetlands, less than half have strong regulations where drainage is non-compliant, and monitoring is sparse. The majority of plans (60%) restrict damaging activities only in wetlands that are in a schedule or meet criteria for ecological significance; rules in most plans do not protect smaller, often degraded wetlands. Although wetland loss and degradation still occurs in many regions, national and regional rates of loss are not reported. A response requires strong national policies on preventing further loss, the implementation of regulations in regional and district plans, and monitoring of the effectiveness of policies, rules, and non-statutory mechanisms. A combination of bottom lines for statutory regulation, voluntary incentives including support for fencing, and effective practical management is required.