Introduction
Auckland's indigenous biodiversity is unique with a diverse range of ecosystems reflecting the complex physical environment of the region. Natural ecosystems and indigenous biological diversity contribute to the character and identity of Auckland and distinguish it from other regions of New Zealand. Auckland contributes significantly to New Zealand’s biodiversity with a high diversity of habitats for its size. The special landscape and sense of place that is Auckland is determined in part by the health, variability, extent, and range of terrestrial, freshwater, coastal, and marine ecosystems. Healthy and functioning ecosystems also contribute to improved water quality, soil conservation and carbon sinks, as well as providing opportunities for our recreation, economic, and cultural use.
However, development has impacted on Auckland’s natural heritage resulting in loss of habitats and a reduction of biodiversity. Auckland also has significant animal and plant pests that have naturalised and threaten the viability of indigenous ecosystems and species. Urban expansion and development, changes in coastal and rural land uses, and the ongoing degradation from pest species continue threaten the maintenance of our indigenous biodiversity on land.
Coastal and marine ecosystems are subject to change, damage or destruction from inappropriate subdivision, use and development, as well as natural processes. The quality of the coastal environment is fundamentally determined by the presence of a diversity of ecosystems and by their ability to function as biological systems. This underlies the life-supporting capacity of the CMA.
Parts of the CMA have natural and physical values of regional, national and international significance. These areas are vulnerable to the adverse effects of inappropriate subdivision, use and development and require a greater level of protection than the coastal environment generally. Areas of high ecological value have been identified as Significant Ecological Areas (SEAs). The SEAs have been identified using the significance criteria listed below. Sites are significant if they meet one or more of these criteria. The SEAs in the marine environment have been identified as two types of areas (Marine 1 and 2) reflecting the different size and vulnerability of these areas.
SEA-Marine 1
SEA-Marine 1 include areas which, due to their physical form, scale or inherent values, are considered to be the most vulnerable to any adverse effects of inappropriate subdivision, use and development. They include regionally or nationally rare habitat types, such as saline herbfields, as well as the best examples of saltmarshes and mangroves in Auckland. Some identified SEA-Marine 1 form part of an ecotone (sequence) of coastal vegetation which extends from significant native vegetation on land into saline vegetation and intertidal and subtidal seaweed communities.
Parts of Auckland are of national and international significance as a seasonal home to tens of thousands of migratory wading birds from the arctic and sub-arctic and the South Island, as well as a permanent home to many more birds. The Manukau and Kaipara Harbours and the Firth of Thames are the most important areas, and other harbours and estuaries form part of a regional network of feeding and roosting sites. Other threatened, endangered and more commonplace birds, breed and roost in sand dunes and coastal vegetation, and feed in the adjacent CMA. SEA-Marine 1 status has been given to key roosting areas and to parts of the foreshore adjoining known bird nesting areas.
SEA-Marine 2
These areas are of regional, national or international significance that are generally more robust than SEA-Marine 1. Many areas still require more protection than that accorded under a general coastal marine zone as their physical form or inherent values make it more difficult to avoid, remedy or mitigate any adverse effects on the environment. SEA-Marine 2 include the main intertidal banks of Auckland’s harbours and estuaries, which are the key feeding grounds for international and national migratory wading birds. Often these areas surround the high tide roosts contained within an identified SEA-Marine 1. Areas of mangroves which are of regional importance because of their size and degree of intactness, or areas of rare or uncommon coastal vegetation such as saltmarshes, have been given SEA-Marine 2 status.
The CMA has not been comprehensively surveyed for the purpose of identifying SEA-Marine. In particular, the identified SEA-Marine may under-represent the significant marine communities and habitats present in the subtidal areas of the region.
Explanation and reasons
Auckland contains threatened ecosystems and species and requires effective management to protect and enhance areas important for the long-term viability of our indigenous biodiversity. Increasing resilience of our indigenous biodiversity and enabling adaptation will position Auckland to respond to the potential effects of climate change.
Activities must be managed to protect and enhance indigenous biodiversity, and actions taken to address existing threats and areas of degradation. Effectively addressing these issues requires a combination of regulatory and voluntary efforts.
The objectives and policies seek to promote the protection of significant vegetation and fauna and the maintenance of indigenous biodiversity by:
•providing objective, complementary and evidence based criteria to identify areas of significant indigenous biodiversity in terrestrial, freshwater and coastal environments
•identifying areas of ecological significance so as to provide greater certainty to people managing and using areas with these values
•promoting restoration efforts to improve the quality, functioning and extent of indigenous biodiversity, and to remedy, mitigate and offset adverse effects of activities
•promoting the identification and enhancement of ecosystem services afforded by indigenous biodiversity
•providing for Mana Whenua’s role as kaitiaki, and as owners of land with a high proportion of significant indigenous biodiversity
•proscribing a management approach which avoids adverse effects on significant biodiversity, and requires that, where adverse effects arise, they are remedied, mitigated and offset, so as to ensure activities do not significantly degrade indigenous biodiversity
•providing for reasonable use by landowners and the continuation of existing lawful activities
•providing for the management of mangroves in a way that supports biodiversity values as well as the legitimate expectations of access to, and use of, the coastal marine area
•recognising the vulnerability and importance of coastal indigenous biodiversity, (including threatened marine mammals) and the particular pressure the coastal environment is under from use and development
•directing that activities are undertaken so as to ameliorate the threat of pest, and providing for the establishment and implementation of effective pest management programmes
•recognising the particular threat to Auckland’s biodiversity from kauri dieback disease
•recognising that there are some uncertainties in the management of indigenous biodiversity for which a precautionary response is appropriate.