Sustainability of SPECIES and ECOSYSTEMS

Forest and Bird, Volume 21, Issue 1, 1 February 1990, Page 12

Sustainability of SPECIES and ECOSYSTEMS

We are the guardians of New Zealand's natural heritage of indigenous species and ecosystems. But can this heritage be sustained into the 21st century? And will the resource management law come too late to prevent a new wave of plant and animal extinctions? Forest and Bird conservation officer Mark Bellingham attempts to answer these questions.

EW ZEALAND IS UNIQUE as the world’s largest and most diverse land mass where plants and animals developed without the influence of terrestrial marsupials or mammals, especially humans. Birds and insects occupied the niches and habitats that warm-blooded animals have in other lands. Moa and takahe browsed our forests and giant weta were the mice of the forest floor. Our country was cast adrift from Gondwanaland 80 million years ago, before marsupials swept across Australia, Antarctica and South America. Some of the distinctive Gondwanaland refugees in New Zealand include kauri, the podocarp trees, kiwi, moa and tuatara. Our wattlebirds (kokako, huia and saddleback), wrens (bush wrens and rifleman) and short-tailed bat have no close affinities with other animal groups. They are New Zealand in origin and may represent local biodiversity on the old Gondwana supercontinent. Occasional immigrants arrived; some survived and developed their own distinctive New Zealand forms. Our robins and tomtits are probably derived from the Australian scarlet robin family, but once here they radiated out into different forms. The pukeko group arrived at least twice, the earlier invasion leaving us with the takahe and the latter with the pukeko, which is closely related to the cosmopolitan purple gallinule. But most immigrants would have perished as New Zealand went through biota changes, as land rose and sank, sea levels changed and the climate fluctuated between sub-tropi-cal through to sub-antarctic.

Gradual Change

New Zealand's physical environment and plants and animals have undergone considerable changes since the break off from Gondwanaland. These produced our landforms and New Zealand's indigenous life forms. Cataclysmic changes were usually local, while large scale changes, such as that from a sub-tropical to a sub-antarctic climate,

took 20 million years. The gradualness of this change has allowed the surviving elements of our indigenous biota to avoid extinction. To the first people who arrived in New Zealand from Polynesia, at least 1000 years ago, the new land had an abundance of wild food (birds, fish, shellfish, marine mammals and forest fruit), even if the climate was fairly poor for growing their traditional staple foods

of taro, yam and breadfruit. These Polynesian immigrants also brought kiore and kuri (their rat and dog). A thousand years later when Europeans arrived and colonised, New Zealand had lost 23 percent of its forests and 30 percent of its birdlife, the most notable loss being the various moa species. But with European settlement forest clearance accelerated, wetland drainage started in earnest and native animal species were exterminated at an ever increasing pace. By 1900 some people were lamenting the loss of New Zealand's unique natural heritage and attempts were made to arrest the destruction. This saw the passing of laws for national parks, reserves, scenery protection, bird protection and better management of forests. But the forces of development and destruction still had their feet firmly on the accelerator, and the clearance of forests, wetlands, and tussocklands was accompanied by the continual introduction of exotic predators (rats, mustelids, hedgehog), browsers (possum, wallaby, deer, goats, rabbit, hare) and plants (Clematis vitalba, buddleia, marram, Spartina).

Conservation 1990

Despite the dramatic conservation advances of recent years, we still have the following situation: e A land and water planning system that is biased towards development and destruction of indigenous natural values. e No protection for the habitats of native wildlife.

e No protection for rare and endangered ecosystems. e An unenforceable national wetlands policy. @ The destruction of New Zealand rainforests by export woodchipping driven by Japanese demand for hardwood pulp. e An underfunded conservation sector which cannot control serious outbreaks of noxious animals (deer, thar, goat, possum) or is unable to purchase many threatened areas. The past decade has seen some slowing down of the loss of natural ecosystems, in particular the end to forest clearance and wetland drainage incentives and an end to these activities by Government departments. But the onslaught has continued through the inadequacies of land and water planning for

private land and because of the outdated attitude of the politicians, planners and engineers who keep it running.

Resource Management Law

The new resource law could be a major breakthrough for our indigenous heritage. In its draft principles "regard must be taken of the importance of the maintenance of natural features and the effect on ecosystems, ecological processes and biological diversity.’ Our challenge now is to get these lofty words into national, regional and local planning systems for land, water and coastal use. The new Heritage Order in our resource laws now gives us a chance to protect and preserve special features of our natural heritage that are threatened. But the large sums needed to compensate private landowners from destroying areas protected by such a heritage order will mean that these will only be used for small sites, which are generally insignificant to threatened native species and ecosystems. It took conservation groups ten years to get some protection for forests, wetlands and coastal areas in the Town and Country Planning Act. We must hope the new planning system will prevent threatened species and ecosystems from being further compromised by so-called "balanced" decisions, which invariably favour development and destruction of natural heritage values.

Species and Habitat Protection

Changes to the planning system are not

enough. The Wildlife Act needs some urgent changes. Protected species need habitat protection and especially threatened plant species which comprise 10 percent of our higher plant flora. The Wildlife Service, Botany Division of DSIR and the Conservation Department have spent millions of taxpayers money documenting the habitats of these threatened species (and their decline). Habitat protection is needed to ensure we do not extinguish more of our natural heritage.

Exotic Plants and Animals

After several decades of controls on exotic animal imports, the floodgates are now being opened again, aided and abetted by the Ministry of Agriculture and Fisheries. We have

seen marron crayfish and chinchilla smuggled into New Zealand, and applications to import exotic abalone, catfish, crocodiles, antelopes and many more. We can expect in the next few years a new onslaught on our natural ecosystems from exotic pests, especially on our waterways, as some of these speculative farming ventures fail and the animals are released (for example, ferret releases from failed fitch farming, see Forest & Bird November 1989). Goat and deer escapes (the latter into Northland forests) are further examples of a mounting problem. This situation will be exacerbated if some New Zealand deerstalker elements and would-be game managers in officialdom are able to relax control provisions for noxious

animals, such as thar and deer, and have them recognised as "game animals." This could prevent the eradication of deer and other noxious animals from threatened ecosystems in Fiordland or Northland or from islands, such as Great Barrier or D’Urville, or thar from the Southern Alps. It also ignores the fact that deer, goats, possums and other wild animals are pests which threaten New Zealand's biodiversity. Quite simply, control and, where achievable, extermination programmes, are vital to prevent some of our native species from becoming extinct or to head off unacceptable degradation of natural areas.

Hope for the Future?

In the last 150 years, one of the greatest uncontrolled experiments in natural history has occurred in New Zealand and in the process exacted a terrible toll in the rate of species and habitat loss. DSIR botanists have described the conversion of lowland New Zealand from natives to exotics as an event unparalleled in world botany.

A similar toll has been wrought on native animals in those formerly indigenous ecosystems. From the few studies our scientists are Carrying out (on kiwi, kaka, kokako or yellow-eyed penguin for example), we know that such ancient and unique birds are continuing to decline. Arresting that decline will take a mammoth effort and mean species will have to be managed — not an inviting thought perhaps, but if predators or possums and deer continue to menace native animals, management is the only option for many mainland species. New Zealand must reverse the trend of destruction of our species and ecosystems. We must take a deliberate step to protect our natural values and to enhance those ecosystems and natural areas that remain. Perhaps we could give the original inhabitants of New Zealand a special 1990 celebration gift by:

e giving legal protection to threatened plants and the habitats of all threatened species. e having binding national policy statements for the protection of native habitats, ready for when the resource management law is passed in July. e a nationally co-ordinated and properly funded eradication and control programmes for pests such as possums and goats. e Removal of the moratorium on commercial hunting of thar. This would help ensure that our obligation to pass on New Zealand's treasures to future generations is observed. Our failure to do so will not be forgiven. y&