Environment

Coping with the aftershocks of our arrival: Biosecurity and the history - and future - of New Zealand

Most New Zealanders have grown up with the idea of unwanted biological invaders. But for many years public imagination was fixed on a small number of villains. When I was a child, foot and mouth disease was the apocalypse that waited in the wings. As our economy has diversified, the range of potential scourges has multiplied with it - fruit fly for the horticulturists, gypsy moth for the forest sector.

While most people grasp the economic seriousness of our on-going surveillance battle, the biological and ecological forces at work are much less well understood. They are complex and fascinating.

New Zealand's ecology has been undergoing traumatic change for the best part of a millennium. The evidence for that can be spotted in any major New Zealand museum with their melancholy display cases of long extinct moas, Haast eagles and huias. New Zealand's North and South Islands were the last big islands on the face of our planet to be discovered by humans and it was awfully bad luck for the indigenous species that (save for two species of bat) we were the first terrestrial mammals.

First Maori, then Europeans, walked into an ancient and separate island ecology full of niches that had been filled by birds. Neither people understood what they were unleashing. Maori created havoc through fire and the hunting of prized bird species. The colonising British in the nineteenth century started another wave of extinctions as they laid waste to the forests and introduced a vast new array of animals. In the absence of their traditional predators, many failed to behave as expected.

The chaotic succession of disasters is part of our folk lore: virgin landscapes laid low in the cause of grazing livestock; pastoralism brought to its knees by plagues of rabbits; stoats and weasels introduced to attack the rabbits turning, instead, on native birds. But this wasn't just a nineteenth or early twentieth century phenomenon. Until quite recently a tidal wave of exotic plants has continued to pour into the country as gardeners have sought novelties for their flowerbeds and shrubberies. Like the rabbits before them, they haven't stayed where they were supposed to.

We now have two distinct ecosystems, neither in a particularly stable state. There are the original indigenous ecosystems, pushed to the margins of the landscape in places like National Parks and groaning under the onslaught of possums and other pests. Then, superimposed on the indigenous ecology, is a collection of exotic grassland and forest ecosystems. They are not, however, anything like the Northern Hemisphere ecosystems which they mimic. Because all sorts of bits are missing. Lots of predators and competing species didn't make the journey which has meant enhanced productivity and vitality for key sectors of our biological economy.

In short, we started with an indigenous ecology full of unique species that had no competitive resilience. Europeans then superimposed incomplete and alien farming ecosystems that were full of gaps and thus wide open to invasion. The result now is a complex ecological tapestry with all sorts of fraying edges and empty niches for invasive latecomers. We have been conducting a vast and uncontrolled ecological experiment in real time across an entire country (although we've only been conscious of doing so for a few short decades and we still haven't figured out the rules). And while the days of intentional heroic importations are over, the rising tide of trade and tourism means the risks of accidental introduction have never been higher.

The economic case for keeping unwanted pests out is well understood. The environmental case - built on a desire to preserve our unique Gondwanan heritage - is more recent. But together, they provide New Zealand with a more powerful motive for guarding its biological assets than exists in most other countries.

This sets us apart from the bulk of the world's people, who live in continental settings where political borders bear no relationship to ecological boundaries. While customs declarations in most countries routinely ask whether travellers are carrying living material with them, there is not the sense of impending - but preventable - crisis that applies in New Zealand. There are reservoirs of all sorts of nasty things lurking throughout Africa and Eurasia. But the lack of natural moats means that what is possible from a biosecurity standpoint is very different.

Interestingly, biosecurity as we use the term has not really penetrated public consciousness. If you talk of biosecurity in the Northern Hemisphere most people think you are talking about either bio-terrorism or the unmanaged escape of genetically modified organisms. These are, of course, elements of what biosecurity in its broadest sense is all about - seeking to manage human health and economic risks posed by the unwanted release of biological agents. And herein lies one of New Zealand's most interesting opportunities.

Whereas for most people the risk of unwanted biological incursions is a new phenomenon, it's something New Zealanders have lived with for nearly 200 years. A large chunk of our economy is reliant on biosecurity and knowing how to maintain it. It should be an area where our skills outstrip those of many other countries by accident of the constant state of readiness we have to be in. This is the age of bio-sensors and analytical techniques that can detect, identify and monitor the mind-bending array of organisms that, for totally different reasons in different parts of the planet, people are trying to keep at bay.

Rather than trying to search for the knowledge economy in traditional hi-tech areas, shouldn't we be seeing our biological vulnerability as an opportunity? Because the huge array of skills we have assembled to guard our borders - and no doubt begrudged as a costly burden - is, in fact, the intellectual front line of a struggle that is rapidly gaining global currency.

We may not have got to grips with the biological forces at work in New Zealand. And we will never be able to keep everything out forever. But as we have sought to come to grips with the challenges, we have unwittingly developed the skills and technologies that could be the key to completely new sources of wealth - rooted in the same traditional industries that both built the nation and unleashed many of its problems.

* Simon Upton was New Zealand's first Minister for Biosecurity