Better captive than dead

Zoos must change if they are to become the arks of the 21st century.

The World Conservation Union (aka IUCN) tells us this month that 900 species are in critical danger of disappearing from the wild in the next century, including such wonders as the huge and shaggy Siberian tiger; and a fifth of all mammals must be considered "threatened", including most of the big cats and a fair proportion of our own closer relatives, the primates. The only surprise is that things are not even worse - but then they almost certainly are, since the IUCN tends to err on the side of caution.

We have made a world that simply is not designed for wild animals, and if we seriously want them to share our planet then we must re-think just about everything we do. Until we can get ourselves in order - which will take a few centuries - animals will have to rely more and more on zoos. Few zoos realise this and many, including some of the best known, present a public face that discourages debate about the enormity of such a project.

Task one is to demonstrate to sceptics that conservation is worthwhile and to do that we need robust arguments, which means they have to be true. It is not true, unfortunately, that well-protected environments with their natural abundance of species are generally likely to pay their way - at least when put against more bullish human enterprise. Thus conservationists argue that modern economies are propped up by tourism, which increasingly can mean eco-tourism, and that "biodiversity" is a resource: a reservoir of drugs and of genes that can be transferred to crops and confer resistance to disease and drought. But a reserve for mangroves, say, is an economic wasteland compared to the marinas and hotels that could replace it; and if a tropical forest grows over a seam of gold, then simple economics demands that the forest must give way. Biodiversity may be a resource but it is rarely cost-effective to screen millions of species for the occasional pharmacological gem. And eco-tourism is a small proportion of tourism as a whole, while the non-eco part is mostly destructive.

Neither is it true that an environment with millions of species is necessarily more "stable" than one with fewer. Tropical forests with hundreds of species of trees are no more stable than temperate forests that may be almost monocultural. Replace tropical forest with a few well-chosen strains of eucalyptus and they could be maintained effectively forever. Of course, if you change the nature of the habitat - turn forest into grassland, for example - you may run into trouble. But if you follow a few common sense rules and make sure you keep the things that really matter - like the plankton in the sea that takes up atmospheric carbon dioxide - then, in principle, you could reduce the diversity of species a hundred-fold and be as "stable" as ever.

In fact, the more you look, the more you realise that the only truly defensible reasons for bothering about wild species are those that seem most fragile. The first is that our fellow creatures are beautiful and our lives would be sadly impoverished without them; tigers are worthwhile in the way that the National Gallery is worthwhile. The second is that to conserve our fellow species is right. Like all moral positions, this can be defended with endless argument; but all moral arguments in the end serve only to justify the initial instinct. We can simply assert with the obduracy of a prophet that we ought not to destroy; and if we think we need a principle, then the feudal concept of noblesse oblige is good enough.

But the task is much, much bigger than is commonly argued and if we believe conservation is worthwhile then we have to be radical. The most obvious solution is simply to create more wildlife reserves, the biggest of which are called national parks. Indeed, this is vital but it's nothing like the panacea that governments would have us believe. No population of wild animals can be considered viable long term unless it contains several hundred individuals and by this criterion, most existing national parks are simply too small, especially for big predators. Even Yellowstone seems unable to hold viable numbers of grizzly bears. Tigers need up to 100sq kms each, so any tiger reserve smaller than Yorkshire is strictly pro tem. All national parks are beleaguered: Yellowstone by bureaucracy, summer traffic, and neighbouring cattle farmers who hate bison because they carry brucellosis; and many designated reserves in the Third World harbour more domestic cattle than wild animals, while some marked "forest" on the map seem to have lost all their trees.

If we add in the dimension of time, the position seems even worse. All national parks are temporary because they are founded by particular societies at particular times and, as Thomas Paine pointed out at the time of the French Revolution, no society has the power or even the right to tell its successors what to do. So, what- ever we designate may be de- designated. Besides, we know that in the next few thousand years the climate will change dramatically, just as it has over the past few thousand; indeed, greenhouse gases could produce a climatic shift within decades. Animals survived the ice ages and the warm inter-glacials by migrating - reindeer down to the south of France, hippos up to Yorkshire and beyond; now they would be trapped like rats in their national parks. So the parks need to be linked by broad north-south corridors. But this is not going to happen. Paris, Nairobi, and suchlike places are in the way.

Then there is the small matter of human population. While one UN department describes the fate of wild animals, another has lately been telling us that human numbers will reach six billion by 2000 AD and, at the present rate of growth, 48 billion by 2120. Even if it were technically possible to sustain such numbers there is very little time for preparation. Obviously, something dramatic has got to happen in the next century and large-scale human drama, even at its most benign, is bound to complicate the lives of our fellow creatures even further.

There is just one chink of hope - a statistic which shows that the percentage increase of the human population is going down. If this fall- off continues, then human numbers would stabilise at around 12 billion by the mid 21st century, remain stable for about a thousand years, then start to fall. After that, the world could breathe more easily and land could, in theory, be turned back to wilderness, as it could now through the temporary policy of set-aside.

So, if we and our fellow creatures can get through the next thousand years, then life could start to get easier, provided we do not make too much of a mess along the way. None the less, for at least 500 years things will get more difficult, particularly during the huge changes of the next century. We have to do what sensible generals do when they know the worst is still to come - define the do-or-die position, beyond which retreat is unacceptable.

What is this fall-back position? Item one: defend and manage as much of the remaining wilderness as possible, as many people are now striving to do. Item two, however, is to accept that for many species - like tigers - that will not be enough. We also have to get them into safe havens and breed them, just to keep the numbers up.

This is where the zoos come in. If we take conservation seriously then we must take zoos seriously, and in practice we do not. We should see them, like opera houses and museums of fine art, as necessary components of civilisation, and give them at least as much public support. At present, British zoos receive no regular government funds. In their turn, zoos must show that they are worth taking seriously. Gerald Durrell's Jersey zoo already does so; but too many, like London, have yet to learn that they can be serious without being pompous or aggressive, and attractive without being frivolous.

In general, if we really think conservation matters we need to act radically and effectively re-design the world. But as Lao-tzu commented, a journey of a thousand miles begins with a single step. And one of the first steps is simply for zoos to change their image.