Who would really want to eat a gorilla?

In many regions of Africa, bushmeat makes up 80 per cent of the population's animal-protein intake. Some species face extinction. But is this simply an animal-rights issue? Fred Pearce investigates

Some of the world's most endangered wild animals are, quite literally, being eaten to death. Dozens of species of great apes, monkeys, crocodiles, snakes and birds face extinction in the tropical rainforests of central Africa as a result of them being hunted for food. The growing "bushmeat" trade is now identified by some conservationists as perhaps the single greatest threat to the existence of the rarest animals. Within a generation, the forests could be empty because of this insatiable appetite for filling the pot.

In the first study to gather hard, statistical evidence on the scale of the problem, John Fa of the Durrell Wildlife Conservation Trust in Jersey has calculated that around five million tons of wild meat is eaten in the Congo basin of central Africa each year. This is five times that of previous estimated figures, and equivalent to a staggering 90 per cent of all the animals living in the forests at any one time.

While reproduction has kept the populations of most species limping along, this cannot go on, Fa says. Hunting is proceeding at anywhere between twice and five times the rate at which animal populations can be sustained naturally without facing eventual extinction. There will soon come a point when there are too few animals to feed a fast-growing human population.

Fa concludes that extinctions of many important and well-known jungle species, such as chimpanzees and great apes, will begin "relatively soon" and be widespread within 50 years, as the rainforest becomes a virtually empty "ghost" jungle.

In fact, in the neighbouring rainforest region of West Africa, the first primate victim has already gone. Two years ago, scientists reported the extinction of the Miss Waldron's Red Colobus, brought down by bushmeat hunting. It was the only primate to become extinct during the 20th century, but the 21st century is likely to see many more go the same way.

Bushmeat has always been the staple diet of forest dwellers. But as the human populations of African countries soar and cities grow, their economies have failed to produce domesticated sources of meat. Much of the continent, urban as well as rural, still relies on the bush to meet its protein needs. They eat wild elephant rather than pork, or snake rather than chicken. In most households, domesticated meat is eaten only on special occasions.

Hunting takes places almost everywhere, including in national parks, which ought to be refuges where the animal populations can recover undisturbed. Village hunters who once killed for the pot now also kill for cash. They sell at the roadside. Small boys standing by the road and holding up giant rodents by their tails is a common sight across Africa.

There are no official statistics for the trade in bushmeat. Much of it is, in any case, illegal. But, legal or not, the trade is increasingly commercialised and there is also a growing international market. Anti-bushmeat campaigner Karl Ammann says he has tracked convoys of bicycles carrying tons of smoked elephant meat down jungle tracks from the Democratic Republic of the Congo (formerly Zaire) into the neighbouring Central African Republic, where it turns up shrink-wrapped on supermarket shelves.

Monkey meat, in particular, goes further – smuggled in aircraft holds to the high-priced markets of Europe. In London, Dalston market has recently been identified as an important outlet for smoked monkey.

The Congo basin of central Africa is the world's second largest rainforest region, exceeded only by the much more sparsely populated rainforest of the Amazon basin. In this part of Africa, most of the population still lives in the bush: some 34 million people in all, with millions more in surrounding cities. A typical square kilometre of forest contains around 20 people, most of whom get their protein from the animals living close by. Many forests are also being invaded by miners and logging gangs, often working for European companies, who also rely on the bush for their food.

In many regions, bushmeat makes up 80 to 90 per cent of the population's intake of animal protein. If you want meat in central Africa, you go and hunt in the bush or buy from the traders who sell meat smuggled from the bush. Truckloads of bushmeat is unloaded at city markets each morning. It is often virtually the only source of protein available in the markets, and is universally cheaper than domesticated meat.

Fa used dietary studies to estimate just how much bushmeat protein people are consuming. Figures range from 28g of protein a day in the Democratic Republic of the Congo, the poorest country in the region, to 180g in Gabon, the richest. This compares with a UN recommended minimum daily intake of 52g.

But things will get a lot worse as the forests empty. Fa estimates that, by 2050, the bush will be able to supply just 9g per head per day. "At current exploitation rates," says Fa, "bushmeat protein supply will drop by 81 per cent in all countries in the region within the next 50 years. Malnutrition is likely to increase dramatically."

If people are not to starve, he says, the difference will have to be made up. And the sooner the better. "If cheap meats were available for the people who buy bushmeat, the demand for wild meat would drop," he says. That, rather than draconian bans on trade in the staple diet of the population, is the solution to the bushmeat crisis.

Using data collected in local markets, Fa has calculated the hunting rates of more than 50 species, including antelopes, monkeys, apes, pangolins, pigs, large rodents, elephants, reptiles (such as snakes, lizards and crocodiles), and birds such as hornbills.

Biologists estimate, as a rule of thumb, that large mammals can reproduce 20 per cent of their body weight in a year in the wild. In other words, any rate of hunting higher than that will cause their populations to crash. Smaller mammals may be able to sustain somewhat higher hunting rates. But none can cope with the current carnage. Fa calculates that the weight of all the carcasses removed from the forest by hunters in a year is now 93 per cent of the estimated weight of all the animals in the jungle at any one point in time.

Until recently, most environmentalists regarded bushmeat hunting as a side-issue in their efforts to conserve Africa's wildlife. Much less important than ivory hunting, for instance, or the destruction of rainforests by logging companies. But increasing numbers now agree with Fa that "hunting for meat currently represents a greater threat. It is what is driving many species to extinction".

Research published last month on how species go extinct under hunting pressure suggests that it is almost always the big animals – the ones we know and love – that die out first. This is partly because there is more meat on them, and because they are more attractive prey. But, says Nick Dulvy of the University of East Anglia in Norwich, "large species also tend to mature later and have lower reproduction rates, so they are less able to replace the numbers killed by man".

In the jungle, big means vulnerable. In central Africa, the animals most at risk of disappearing, says Fa, include the great apes, forest baboons such as the mandrill, and antelopes known as duikers. But there is also growing concern about the fate of elephants. In many areas, hunters are increasingly killing elephants for their meat rather than their tusks.

Fa's research has led him to come out against the conventional green response to the slaughter of wildlife – demands for bans on hunting and trading in the endangered species. He says that people who think the solution is to stop the illegal hunting are in danger of behaving like Marie-Antoinette who, on being told the French had no bread, replied "let them eat cake". Pork and chicken are no more available in central African supermarkets than cake was in pre-revolutionary Paris.

Right now, the majority have got no alternative but to eat bushmeat, and all the more so as many of the countries are going backwards economically, with virtually no government and constant civil wars. Per-capita food production on farms in the region has not risen since the 1960s, and in some countries it has fallen by 40 per cent. Africans are almost literally going back to the bush, as they become ever more dependent on bushmeat to survive. And, of course, the one thing that the constant civil wars do supply them with is guns and other weapons to go hunting with.

"We are understandably horrified by wild animals, especially primates, being killed for food," Fa says. "But we must remember that bushmeat is a cheap source of protein for many malnourished people in Africa."

Bushmeat hunting, then, is no longer an animal-rights issue. It is a human rights issue. To solve it, the biologist has turned social scientist. Rather than concentrating on the biology of the animals, Fa says that we have to understand the social and economic problems of the hunters first. Only that way, he believes, can the animals of the African forests – and the people –be saved.