Rural communities in the Amazon rainforest live alongside an incredibly diverse set of animals. When some of those animals damage and eat farmers’ crops (“crop-raiding”), it creates a challenge for conservationists, who need to understand the lives of the people who coexist with that wildlife.
My colleagues and I recently spent a year in the Médio Juruá region of Amazonas, Brazil, using motion-activated camera traps to take photos of the many animals that live on or near Amazonian farms. Along with interviews of farmers, this enabled us to study which animals cause the most crop damage, how this affects the livelihoods of rural Amazonians and how these communities respond to crop raiders. Our hope was to understand how this issue might affect attempts to preserve wildlife and to offer support to local farmers if they wanted it.
The Médio Juruá region is a vast area of staggeringly biodiverse lowland tropical forest inhabited by river-dwelling communities, who descend from a mix of indigenous Amerindians, European colonists and former slaves from Africa. Our research team (comprising myself, my colleague Professor Carlos Peres, and Hugo Costa from the State University of Santa Cruz) travelled using small boats and dug-out canoes along the sinuous waterways and through the flooded forests. The region experiences a massive ten metre-high annual flood, which has wide-ranging impacts on the local ecosystems and the livelihoods of the human inhabitants.
In the year we spent living and working with the communities of the Juruá, we were fortunate enough to participate in many aspects of life, including learning to harvest the fruit of the acai palm. Many Juruá communities are the descendants of rubber tappers (seringueiros) who were drawn to this region during the rubber boom of the late 1800s. Many still depend on the natural resources of the forest and river for their livelihoods. The incredibly hospitable communities of the region frequently hosted and fed us as we travelled.
Most of the carbohydrates in rural Amazonian diets come from manioc (also known as yucca or cassava). This tough plant grows well on infertile tropical soils and has powerful chemical defences which make it pest-resistant. Farmers grow manioc using so-called “slash-and-burn” agriculture in fields called “roçados”, which are created by burning down a section of forest. They peel, grind, soak, drain and toast the manioc to remove the toxic cyanide which protects the plant from pests. The result of this process is delicious coarse flour called “farinha”, which is commonly eaten with fish soup.
Despite high levels of toxins in raw manioc, some wild animals such as large rodents, deer and pig-like peccaries are able to eat it. These crop raiders can have devastating impacts on human livelihoods, destroying an average of around 8% of each farmer’s crop each year. Farmers estimated that if they did not protect their crops, their losses would be roughly ten times higher. In other parts of the world, large herbivore crop raiders such as African and Asian elephants also endanger the lives of farmers.
Of course, these wild and often endangered species are merely trying to survive in an increasingly human-modified landscape. Poor farmers sometimes resort to killing crop raiders to protect their lives and livelihoods and can end up resenting the conservation organisations who want to protect these species.
To study crop raiding, we set up 132 camera traps in areas next to local roçados, helped by more than 45 people living in the nearby communities.
We captured more than 60,000 photographs and detected over 30 species. We detected everything from fearsome predators such as pumas, to secretive nocturnal giant armadillos, to birds of prey and even primates such as capuchin monkeys.
One of the most feared predators in the area is the jaguar, locally known as “onça-pintada”. We were fortunate to detect this species in several locations. Somewhat unnervingly, we occasionally saw their large fresh prints on the trail as we returned to the community, indicating that we had unwittingly been followed.
Many local residents assured us that this species is “very cunning. They see us, but we don’t see them”. We were also told a local legend that when a jaguar follows in the tracks of a human, it will sniff their tracks to decide whether or not to attack. We can only presume that we smelled so bad at that point that even our footprints were unappealing.
In only one location, our cameras detected a rare red-billed ground cuckoo. This was an unexpected treat. Our colleagues were among the first to photograph this elusive species when they worked along the Xerua river a few years ago.
Some species seemed to rather enjoy the limelight, while others took exception to being monitored. Razor-billed curassows frequently paraded themselves in front of the cameras, whereas a short-eared dog took it upon himself to tear a camera from the tree.
Spending long periods hiking through tropical forests surrounded by an exuberance of living things does come with certain drawbacks. For one thing, there is a bewildering array of tiny lifeforms for whom humans are mere prey. The foot sores in this image are caused by a bacterial infection known locally as “hoi hoi”.
We also conducted 157 interviews with local people, who overwhelmingly identified five species as the most burdensome crop raiders. These were, in order of importance, the large rodent agouti, collared peccary, paca (another large rodent), red brocket deer and, to a lesser degree, the spiny rat.
These species were some of the most frequently detected by our camera traps. They were also among the most heavily hunted species. None of these crop raiders are considered highly endangered (though the International Union for the Conservation of Nature doesn’t have enough data on red brocket deer to classify them). Other studies have also found that these species can tolerate a moderate level of being hunted for food.
We were encouraged to find that, despite the costs of crop-raiding to rural Amazonian communities, it did not seem to constitute the bitter “human-wildlife conflict” that other researchers have identified. In fact, because the most damaging crop-raiding species are fairly common, crop protection methods including hunting may not be a major threat to wildlife in this region.
Rural tropical communities are often encouraged by people from other countries to conserve their biodiverse surroundings and are criticised for hunting that helps them survive. We hope that our study has shed some light on the challenges faced by Amazonian communities who attempt to coexist with wildlife. They could use our results as the basis of a plan to manage the species that they hunt, just as they have implemented plans for sustainable rubber tapping and fishing in partnership with international organisations.