Bushmeat on the menu: untangling the influences of hunger, wealth, and international commerce.

At a market in a warehouse, a dozen or so vendors display tables stacked with smoked meat priced from $5 to $8 per pound. Sellers cheerfully answer questions about their wares, which come from monkeys, small antelopes, and rodents such as the cane rat. Biologist Justin Brashares, who studies wild animals that are hunted for meat in Ghana, paid a visit to this market last year, not in rural Africa, but in New York City. Given that the meat was almost certainly smuggled into United States, the market "was more open than I thought it would be," says Brashares of the University of California, Berkeley.

He discovered the market after falling into a conversation with a New York cab driver who had originally come from Ghana. "I was asking the cab driver about his favorite bushmeat and what he missed being here," recalls Brashares. "He said there were certain things he missed, but he could get a lot of it in New York."

The driver ended up taking Brashares to the unadvertised market. "It was one of the most striking things I've ever seen," Brashares says. He adds that many people don't realize that there are bushmeat markets all over the world. There's a large one in Paris, but many other cities, including San Francisco, Chicago, and Montreal, also have them, he says.

Brashares' New York adventure highlights several themes in current investigations of African bushmeat. First, researchers are exploring why people eat these meats. Is it because they don't have much else to eat? New York certainly offers alternative foods. In such a ease, is bushmeat a prestige item or a nostalgia food? And does increasing wealth actually fuel the trade? Furthermore, how do the activities of other countries influence the demand for bushmeat in Africa? The answers to these questions will have global ramifications.

"People tend to think, 'Oh, those poor Africans can't manage their resources,'" says Brashares. "We in the developed world need to realize we have a direct role through our exploitation of resources both in those countries and in the waters adjacent to those countries. This is an international problem."

MEAT COUNTERS People have always hunted wild animals for their flesh. What's changed, according to wildlife biologist Elizabeth Bennett of the Wildlife Conservation Society in New York City, is that so many hunters now stalk the tropical forests of the world that animal populations there are dwindling dramatically. In some cases, whole species are at risk.

Tropical forests may look lush in photos, but they're only one-tenth as productive as savannahs are in producing animals hunted for their meat, according to data assembled by Bennett and his colleague John Robinson. If people got all their protein from local wild meat, tropical forests typically couldn't support more than one person per square kilometer over the long term. Yet Bennett reported that, by 2002, hunters in central Africa were taking six times as much meat as would amount to a sustainable harvest.

Overhunting ranks as a major problem for a third of the mammals and birds threatened with extinction, according to a recent analysis of the Red List, in which the International Union for Conservation of Nature and Natural Resources reports the degree of peril for plant and animal species worldwide. For 8 percent of mammals in greatest peril, overexploitation is the major threat.

The bushmeat trade takes dozens of species, from elephants to birds. For example, a new report by longtime bushmeat analyst John Fa of the Durrell Wildlife Conservation Trust on the island of Jersey lists 71 species of mammals that are traded in seven countries of west and central Africa: Cameroon, Equatorial Guinea, Gabon, Congo, Democratic Republic of Congo, Central African Republic, and Ghana. Hunters at the 36 villages and towns sampled were killing about 200 animals per hunter per year, Fa reports in the January Biological Conservation.

Of that meat, nearly three-quarters, by weight, came from hoofed animals such as antelopes called bay and blue duikers. However, the list also includes aardvarks, horny-scaled anteaters called pangolins, and 22 species of primates.

The primates have raised the most public alarm. The Ape Alliance, a Cambridge, England-based coalition of primate-related organizations, has reported that while primates don't represent a large proportion of the whole trade, overhunting is a serious threat c to chimpanzees, gorillas, bonobos, colobus monkeys, and some other species.

The bushmeat trade is becoming a human-health concern too. Studies of AIDS viruses have suggested that the current pandemic can be traced back to as many as eight independent transmissions of a virus from African monkeys and apes to people.

FISHING GONE According to one standard explanation, the bushmeat trade thrives when other sources of protein fail. A few years ago, Brashares realized that he could use data already available to test this idea.

The U.N. Food and Agriculture Organization has long-term records that detail fish catches offshore of Ghana. Brashares put together these numbers with routine wildlife-population data collected by biologists working in Ghana parks. He and an international team of collaborators assembled information on 41 species of land animals from some 700 censuses conducted in six nature reserves between 1970 and 1998.

Fish rank as the main animal-protein source in west Africa, Brashares says. Yet from 1965 to 1998, the total marine fish catch varied as much as 24 percent from one year to the next. Working with models of ecosystems, the researchers calculated the marine fish supply per person and compared it with calculations of the mammalian biomass roaming the wilds.

Fish catches and mammal populations moved up and down together. They rose in the early 1970s, plunged around 1980, and have stayed close to flat or risen slightly in the years since then. This pattern fits the scenario that bad years for the fishing fleet drive people to hunt more animals on land.

The size of both population declines worries Brashares. The fish stocks in the Gulf of Guinea, where most of the Ghanaian fishing fleets work, declined at least 50 percent over the 33 years that the researchers considered. The wild-mammal population, measured as total biomass, plunged 76 percent. Depending on the park, 16 to 45 percent of the species monitored became locally extinct during that period. Numbers, however, soared threefold in Ghana for one mammal--Homo sapiens.

To check for confounding explanations of the correlation between fishing and hunting, the researchers looked to see whether the fish and mammal patterns matched the ups and downs of rainfall, seasonal temperatures, gross national product, or oil prices. However, the scarcities offish and mammals matched only each other.

A survey of 12 village markets in Ghana supplied more evidence, says Brashares. From 1999 to 2003, as fish got scarcer and their price rose, there was an increase in the amount of bushmeat sold, he and his colleagues reported in the Nov. 12, 2004 Science.

Their research represents "the first to show empirically with a fair amount of data that protein shortages increase bushmeat hunting on a large scale," Brashares says.

He and his colleagues also found an international link: The bushmeat trade reflects the fishing quotas set for the European Union (EU) fleet off the coast of Africa. These fleets were the biggest fishing operation in those waters.

The crash in fish stocks offwest Africa correlates with a 10-fold increase in the amount of fish that the fleets were permitted to catch. Brashares points out that the EU handsomely supported the fleets of its countries by paying for their access to African waters and subsidizing the costs of fuel and boats. Between 1981 and 2001, EU support for fishing in foreign waters jumped from $6 million to $350 million.

Environmental activists have charged that European countries underpay countries such as Ghana, so the EU fleet fishing off the African coast is "artificially profitable, says Brashares.

The link that Brashares' work reveals between fisheries and bushmeat is "really important," says Kent Redford of the Wildlife Conservation Society in New York. Until this study, he says, "we have been very poor in connecting the marine realm with the terrestrial."

NOT SO FAST As Brashares has pointed out, protein shortfalls tell only part of the story--and they certainly don't explain the bushmeat markets in New York and Paris. Other research is looking at bushmeat not just as a critical protein source but also as a sign of increasing wealth.

A household survey of bushmeat in Gabon, for example, has found that wealthier households ate more meat, including bushmeat. "Although some argue that increasing wealth may lead to decreasing consumption of wildlife, our results suggest the opposite," say David Wilkie, an anthropological ecologist based in Waltham, Mass., and working for the Wildlife Conservation Society, and his colleagues. The team reports its findings in the February Conservation Biology.

In this survey, as overall wealth increased, people on the lower rungs of the economic ladder had bigger jumps in bush meat consumption than did people on higher rungs. "Even a small increase in wealth in poor rural families, about a third of the country's population, could easily drive a large increase in bushmeat consumption," the researchers conclude.

"There is a very real, very deep, very longstanding preference for the consumption of wildlife among Africans coming from forested regions," says wildlife biologist Heather Eves, who surveyed bushmeat in the Republic of Congo and now heads the Bushmeat Crisis Task Force, based in Washington, D.C. In figuring out what to do about bush meat, such tastes "cannot be ignored," she says. "Are you going to tell Americans they can't have turkey for Thanksgiving?"

Brashares notes that fans of bushmeat have explained to him at length how to appreciate the best of certain species. No, it doesn't all taste like chicken, he says. He finds that much of the meat tastes gamy. "Some people describe cane rat as sweet, but I never discovered that," he says.

Doing something to preserve the wildlife now being overhunted obviously requires working with the Africans who live in the forests, says Redford, and this demand raises tough questions for the conservation community. He says that activists for reducing poverty accuse conservationists of catering to elitist protectionist traditions at the expense of native people. As Redford summarizes the charge: "Protected areas have been the playground of the wealthy classes."

Demanding that forest people who have few resources stop hunting bushmeat can be a lot to ask without providing alternatives. Hunting can have a big impact on household income among the poorest of the poor. Emmanuel de Merode of the Zoological Society of London and his colleagues analyzed 121 households in an agricultural community in the Democratic Republic of Congo. Each family lived on less than the equivalent of US$1 per day. More than 90 percent of both the bushmeat and the fish that a family caught was sold rather than eaten at home, the researchers report in the January Biological Conservation.

During past decades, some conservationists have argued that a good program to protect the environment would improve the lot of local people, says Bennett. From afar, the idea looks beautifully logical: Reduce poverty in tropical forests, and forest dwellers will have access to food without hunting bushmeat.

But that goal has proved elusive, Bennett warns. Too often, the most impoverished of the forest dwellers have slipped through the cracks of aid programs, and increasing wealth has fueled, rather than extinguished, the bushmeat trade.

GLOBAL APPETITES The biggest threats to wildlife, though, don't come from the small rural villages where people eat the local catch or trade it, says Eves. Instead, she points out the bigger men ace from "a village of hunters, each of whom has 100, or maybe 200, snares running through the forest, and traders coming in from other countries and carting these carcasses across borders to urban markets."

A study of the bushmeat trade in Sekondi-Takoradi, Ghana's third-largest city, for example, attributed much of the demand there to large numbers of men who had moved to the city in search of work. International commerce, such as a rush of oil exploration, can create such a boom.

In Sekondi-Takoradi, 85 percent of bushmeat sales come in what are called chop bars, where the proprietor offers the meat in a stew, according to Guy Cowlishaw of the Zoological Society of London and his colleagues in the February Conservation Biology.

The great logging ventures in tropical forests of the world also have a huge impact on wildlife, according to Bennett, Robinson, and Redford. They point out that timber operations are moving into some 50,000 square kilometers of tropical forest a year, much of which was previously remote. With new roads and new demand among workers in logging camps, the bushmeat harvest surges. In the Congo basin, bushmeat catches per person near logging roads have been measured at three to six times the harvests in communities far from the roads.

Citing a similar scenario, the Bushmeat Crisis Task Force charges that a surge in mining of columbo-tantalite, a material used in cell phone capacitors, is opening even some supposedly protected parks to increases in the bushmeat trade.

With the puzzle of now to alleviate poverty and cope with a fevered bushmeat market, some development specialists have suggested promoting a legalized trade in bushmeat.

Eves remains skeptical. "There is no evidence of sustainable trade where bushmeat is transported for long distances, not when biodiversity itself is being conserved," she says.

The few reports of sustainable bushmeat harvests focus on rodents in logged areas. "That's very different from talking about sustainable harvests from a primary forest full of elephants and gorillas and pigs and hippos and crocodiles," Eves says.

To tackle the overhunting of wildlife, Eves calls for a mix of approaches. Both forest and urban people need alternative food and income sources to meet basic needs in tough times. The underpaid workers in industry camps that push into pristine forests need ways to feed themselves without emptying the landscape of animals. Governments need help to limit the sale of bushmeat.

"What we have is a toolbox," she says, "and no one tool in it is going to fix the car."