The 1997 report, The State of New Zealand’s Environment 1997, concluded that:
Biodiversity decline is New Zealand’s most pervasive environmental issue, with 85 per cent of lowland forests and wetlands now gone, and at least 800 species and 200 subspecies of animals, fungi and plants considered threatened. …
The main pressures on [native] biodiversity today are insufficient habitat in lowland areas, declining quality of many of the remaining land and freshwater habitats, the impacts of pests and weeds and, for some marine species and ecosystems, human fishing activities. …
The main responses to biodiversity decline have focused on ecosystem and species recovery programmes on offshore islands and extensive pest control operations on the mainland, but the need for partial restoration of representative [native] lowland and coastal ecosystems and for wider protection of marine ecosystems has yet to be addressed. …
Pest control, especially possums, is now a vital means of protecting our environment as well as being important for our economy. Pest control will need to become increasingly safe, humane and cost-effective to remain economically and socially sustainable. (Ministry for the Environment, 1997, chapter 10.)
New Zealand’s biodiversity profile
New Zealand continues to be regarded as a significant contributor to global biodiversity. A comparatively large proportion of our estimated 80,000 species of native animals, plants, and fungi do not occur naturally anywhere else on earth.
While many populations of some of our most threatened species have now stabilised under conservation management, the task of halting biodiversity loss is still a challenge in New Zealand today, as it was in 1997.
Almost 2,500 native land-based and freshwater species remain listed as threatened. All 10 threatened indicator species discussed in this chapter have shown a continuing decline in their habitat range.
In 2007, New Zealand’s biodiversity faces the same pressures as 10 years ago. Introduced animal and plant pest species remain a serious threat to New Zealand’s biodiversity. Native plants and animals that survived the initial habitat modification caused by human settlement continue to be threatened by introduced predators and competitors.
Although 11.7 million hectares (44.8 per cent) of New Zealand’s land mass is in native vegetation in 2007, it is largely restricted to hill country and alpine areas.
Wetlands and lowland forests remain among New Zealand’s most threatened habitats and ecosystems. While these areas are now receiving greater conservation attention, they remain under-represented in legally protected areas. This has implications for the threatened species that require unmodified lowland habitats to survive.
Between 1997 and 2002, native land cover decreased by an estimated 16,500 hectares (0.12 per cent). This total decrease included an increase of 700 hectares of non-vegetative native cover, such as sand and gravel, and a decrease of 17,200 hectares of native vegetative cover. These changes either occurred through conversion of land to other uses, or as a result of natural processes.
Since 1997, the clearance of native forests has reduced to low levels as a result of sectoral initiatives and stronger legislation, such as the New Zealand Forest Accord 1991 and the amendments to the Forests Act 1949, the latter of which stopped the clear-felling of native forest. However, other types of New Zealand native land cover, such as broadleaved native hardwoods, mānuka and kānuka, and tall tussock grassland, continue to be modified.
While climate change is expected to have a significant impact on some aspects of New Zealand’s biodiversity, climate-change policies are likely to reinforce current efforts to protect native vegetation.
By international comparison, a high proportion of land in New Zealand is now set aside for conservation purposes. Just over 32 per cent of our total land area is legally protected, either as public conservation land or through conservation initiatives on private land, such as the QEII Trust covenants.
The amount of public conservation land has increased significantly since 1997. For example, 8.06 million hectares were set aside in New Zealand for public conservation land in 2004. By the end of October 2007, a total of 8.43 million hectares were legally protected. This represents an increase of 4.56 per cent in less than three years, which has been achieved partly through the buy-back of Crown-owned land that was formerly leased or licensed to others.
Conservation efforts on private land have also increased significantly. In 2004, a total of 146,280 hectares were registered as formally protected private land. By June 2006, the QEII Trust and Ngā Whenua Rāhui protected a total of 221,473 hectares – an increase of 51.4 per cent over this two-year period.
Introduced species and pest control
Since 1997, controlling pest animals and weeds has received greater attention as a conservation tool. The extent and intensity of pest control effort has increased significantly on both public and private land, driven partly by the increased local funding for pest management made available by regional councils and other agencies. At present, priority is given to controlling pests in the habitats of New Zealand’s most threatened species.
The area managed for targeted pests by the Department of Conservation has increased significantly since 1997. For instance, between 2000 and 2006, areas targeted for possum management by the Department of Conservation increased by 60 per cent. Those targeted by the Animal Health Board have increased by 40 per cent since 2001. Together, areas targeted by the Department of Conservation and the Animal Health Board for possum management equate to around 37 per cent of New Zealand’s land area.
Since 1997, pest control has become more effective as technology and knowledge have improved. The recent introduction of new Department of Conservation traps for stoats, as well as enhanced control regimes on the Department’s offshore and ‘mainland island’ projects, show how pest control is evolving in New Zealand. These efforts have been invaluable in securing habitats for threatened populations and improving conservation techniques and practices.
Stringent pest control to the point of excluding introduced species from areas is a comparatively new conservation strategy. This has enabled endangered species to be successfully reintroduced to reserves on the mainland.
Increased biosecurity is now recognised as a key measure to protect New Zealand from new pest plants and animals. This is important not only for our native biodiversity, but also for the introduced species on which much of our economy depends.
Focus on ecosystems
Conservation efforts on New Zealand’s offshore islands have been invaluable in securing habitats for threatened populations and for improving conservation techniques and practices. Increasingly, habitat with adequate protection for threatened species on the mainland is provided through various initiatives.
Since 1997, our conservation efforts have extended from species-specific conservation, towards ecosystem conservation that enables whole communities of species to survive. This focus on ecosystems recognises the high level of interdependence between some species within the same ecosystem, and is reflected in recently developed national policies (for example, the New Zealand Biodiversity Strategy, 2000).
Attention has also turned to protecting the endangered native species and ecosystems on private land.
As a result of our experience in trying to halt the serious decline in some of our native species, New Zealand is now considered a world leader in conservation and restoration efforts .
In the future, conservation priorities are likely to continue to focus on improved pest control and biosecurity protection, and on increasing the legal protection for those land environments and ecosystems that are not well represented in areas legally protected for conservation purposes. Attention is also likely to focus on the impacts of climate change on our native biodiversity.