By Jonathan Amos BBC News Online science staff, in Salford

We have a duty to make sure it remains for local people and is sustainable for the future of the species affected by it Dr Guy Cowlishaw

The market for wild animal meat, which threatens to wipe out a myriad of species such as the great apes, has become a major issue of conservation concern in recent years.

But scientists from the Zoological Society of London said too many people relied on the food for survival for a simple ban to be imposed.

They argued here for the trade to be controlled in a way that made it sustainable. Only certain critically endangered animals should face a moratorium on hunting, they said.

The researchers made their remarks to the British Association's annual science festival, which this year is at Salford University, Greater Manchester.

No future

"A great many people depend on bushmeat for food and for cash," said Dr Glyn Davies, the director of conservation programmes at the Zoological Society of London (ZSL).

"These are some of the poorest people in the world. You can't just waltz in and say stop."

The figures involved in the bushmeat trade are astonishing.

Recent studies have estimated that between one and five million tonnes of wild animal meat are extracted per year from the Congo Basin in West Africa alone.

It has been shown that a staggering 60% of all mammal species in this harvest have been hunted in a manner that threatens the long-term survival of the population.

The future prospects for some high-profile species like the gorilla are particularly grim, as they are already reeling from other challenges including deforestation and Ebola.

Dry run

The ZSL has attempted to model the trade to see if there are policies that might curb the trade's excesses but still allow local people to exploit a valuable resource sustainably.

Bushmeat: A vital source of protein

"What we've done is create a mathematical model which is, if you like, a virtual bushmeat hunting and market system," said Dr Guy Cowlishaw.

"We can try out experimentally different policies, see what happens and then apply them in the real world - but hopefully more effectively than if we had gone in cold."

The model can show the relationships between species; it will show how heavy hunting of one population can start a harvest of other species that had previously been ignored.

Emotional position

"What we've seen from the model is that smaller species - such as rodents, cane rats and antelope - enter the market just before the larger species - the great apes, the large antelope - go extinct.

"This means it might be possible to use such information as an early warning system for potential extinctions in the next year or two."

The idea that the bushmeat trade should be managed rather than banned will not be welcomed by some conservationists who will argue that, as with elephants, controlled hunting is very difficult to police.

"The bushmeat trade can be very emotive and some of the pictures that come out of the bushmeat markets can be quite horrifying to western eyes but the important thing to remember is that people who are hunting and eating bushmeat generally do not have any other options," said Dr Cowlishaw.