Bushmeat hunting is widespread in the Congo basin. Although forest dwelling peoples have relied and continue to rely on animal protein as part of their diet, commercial trade of wildlife species takes a significant toll on wildlife populations and overall ecological integrity of African rainforest ecosystems.
Although much of the Congo basin is free of permanent human settlement, logging roads facilitate access deep into forested regions. Studies have found that logging roads increase bushmeat hunting not only by improving access for hunters, but also by stimulating local demand and facilitating wildlife trade out of local villages. A study in the Ituri region of the DRC found that populations of duikers and monkeys are vulnerable to increased hunting from growing population. A study in Gabon found hunting had a high impact on duikers (Cephalophus spp.) and forest buffalo (Syncerus caffer nanus), but less impact on monkeys, rodents, and pangolins.
The most commonly hunted species in African rainforest are small ungulates (duikers, a type of antelope), monkeys, and rodents (porcupines), usually trapped with wire and snares. However, new hunters are increasingly targeting with guns large species such as forest elephants and apes. Loss of these larger animals is particularly grave as these species have low population density and are slower to reproduce. Moreover, many of these large species are forest architects that disperse seeds: forest composition can change as long lived heavy seeded trees lose reproductive ability and are outcompeted by short-lived wind dispersed species. In Nigeria, one study found that after gorilla hunting, tree regeneration was hindered by increased seed predation from large rodents. Loss of predators can have similar effects through trophic cascades, affecting populations of prey species further down in the food chain.
In the past decade, populations of forest elephants have dropped precipitously as the international ivory trade has exploded. Forests elephants have traditionally been grouped with savannah elephants by IUCN, but recent evidence suggests they are distinct species. Forest elephants are smaller, have straighter tusks, and are more reclusive. In the forest ecosystem, elephants create trails and clearings needed for other species and disperse seeds over large distances. Studies using transects to observe dung piles documented a 62% drop in population size from 2002 to 2011. The research team from Wildlife Conservation Society find that forests elephants occupy only 25% of their historic range, and the total population is just 10% of its potential, mostly centered in Gabon. The authors have argued that the decline represents a clear extinction threat, and that urgent action is needed. Other studies have documented the affect of conflict in the DRC to illegal ivory trade.
The coexistence of logging and wildlife populations is a crucial issue in the sustainable management of African rainforests. While forest clearings can have mixed effects on wildlife populations, depending on the species, the road network and increased human population associated with logging activity is almost always negative for animals. Studies find that poaching control has a greater influence than logging on elephant and gorilla population, while logging activity clearly reduces chimpanzee populations, even if poaching is controlled. A study by the Wildlife Conservation Society in Gabon found that FSC certified concessions demonstrated improved wildlife management practices. In the Bwidni National Park in Uganda, in the montane forests of the eastern Congo basin, mountain gorillas have slightly increased in population following protected area management and landscape conservation programs. Numerous other organizations support wildlife management in the Congo basin.
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