Bushmeat hunting in the Congo Basin: an assessment of impacts and options for mitigation

Hunting of wild animals is an important component of household economies in the Congo Basin. Results from the growing corpus of quantitative studies show that: a) bushmeat remains the primary source of animal protein for the majority of Congo Basin families; b) bushmeat hunting can constitute a significant source of revenue for forest families; c) bushmeat consumption by low density populations living in the forest may be sustainable at present; d) demand for bushmeat by growing numbers of urban consumers has created a substantial market for bushmeat that is resulting in a halo of defaunation around population centres, and may be driving unsustainable levels of hunting, even in relatively isolated regions; and e) large bodied animals with low reproductive rates are most susceptible to over-exploitation compared with more r-selected species that apparently can tolerate relatively intensive hunting (Mangel et al. 1996). As urban populations continue to grow and economies revitalise, unless action is taken to alter the demand for, and the supply of bushmeat, the forests of the Congo Basin will be progressively stripped of certain wildlife species, risking their extirpation or extinction, and the loss of values they confer to local economies. Consequently, it is essential that a) logging companies are encouraged or coerced not to facilitate bushmeat hunting and transportation in their concessions, b) we develop a better understanding of the elasticity of bushmeat demand, c) that pilot bushmeat substitution projects are supported and their impact on demand evaluated, and d) social marketing activities are put in place to attempt to direct consumer preferences for animal protein away from bushmeat species that are particularly susceptible to over-exploitation.     

Extent and ecological consequences of hunting in Central African rainforests in the twenty-first century

Humans have hunted wildlife in Central Africa for millennia. Today, however, many species are being rapidly extirpated and sanctuaries for wildlife are dwindling. Almost all Central Africa''s forests are now accessible to hunters. Drastic declines of large mammals have been caused in the past 20 years by the commercial trade for meat or ivory. We review a growing body of empirical data which shows that trophic webs are significantly disrupted in the region, with knock-on effects for other ecological functions, including seed dispersal and forest regeneration. Plausible scenarios for land-use change indicate that increasing extraction pressure on Central African forests is likely to usher in new worker populations and to intensify the hunting impacts and trophic cascade disruption already in progress, unless serious efforts are made for hunting regulation. The profound ecological changes initiated by hunting will not mitigate and may even exacerbate the predicted effects of climate change for the region. We hypothesize that, in the near future, the trophic changes brought about by hunting will have a larger and more rapid impact on Central African rainforest structure and function than the direct impacts of climate change on the vegetation. Immediate hunting regulation is vital for the survival of the Central African rainforest ecosystem.     

野生动物狩猎、贸易和狩猎持续性研究进展

过度狩猎和过度贸易是当前生物多样性保护面临的重大挑战。虎骨和犀牛角贸易、东南亚一带的活野生动物非法狩猎和贸易、俄国远东地区及中俄边境野生动物产品非法贸易、热带地区的野生动物狩猎和丛林肉食贸易以及喜马拉雅区域的野生动物非法贸易正严重威胁着全球的野生动物资源。提倡狩猎持续性是解决过度贸易和过度捕杀的途径之一。 在众多的狩猎持续性模型中,“狩猎动物避难所模型”和“空间控制模型”提倡在狩猎区建保护区,有广泛的应用前景。了解偷猎动态和特征及其对濒危动物种群的影响,协调传统医药和野生动物保护间的关系,控制边境地区的野生动物非法狩猎和贸易,以及在保护实践中运用狩猎持续性模型是未来保护关注的焦点。野生动物非法狩猎和非法贸易严重威胁着我国的生物多样性保护和持续利用,但相关的研究却比较少。建议建立野生动物捕杀和贸易的监测机构,加强相关的立法、执法和保护区管理,开展野生动物捕杀和贸易研究。     

Lions,trophy hunting and beyond: knowledge gaps and why they matter

What does trophy hunting (selective hunting for recreation) contribute to wild lion conservation? Macdonald (Report on Lion Conservation with Particular Respect to the Issue of Trophy Hunting. WildCRU, Oxford, UK, 2016) summarises what we know. We identify unknowns, gaps in the knowledge that inhibit conservation planning, including: the causes of lion mortality, the amount of land used for lion trophy hunting, the extent to which trophy hunting depends on lions for financial viability, and the vulnerability of areas used for hunting to conversion to land not used for wildlife, if trophy hunting ceased. The cost of reversing biodiversity loss exceeds income from tourism, including hunting. New financial models are needed, particularly in view of the expanding human population in Africa.     

Assessing trophy hunting in South Africa by comparing hunting and exporting databases

Trophy hunting constitutes a major part of the global wildlife tourism industry and is connected through the export of kills to international wildlife trade. Inconsistencies between kills and exports can contribute to identifying illegal trophy hunting that constitutes a major threat to biodiversity conservation. This paper quantitatively analyses to what extent the data of trophy hunting kills and of trophy exports are consistent using the example of South Africa. Data was extracted from two different sources for the year 2018. These sources were trade data reported under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and its Trade Database on the export of trophy items from South Africa, which is compared with the South African Professional Hunting statistics (SAPHs) containing trophy kills information for each species and the country of origin of the hunter. The data of trophy hunting kills and data of trophy hunting export was found to differ to varying degrees across the countries contributing to trophy hunting and CITES-listed trophy-hunted species. We found that both databases report hunting of the same 28 threatened taxa. On the other hand, the same data reports that hunters of 64 nationalities participated in a total of 4,726 trophy kills, while only 3,131 hunting trophy items were exported from South Africa, to 37 countries as final destinations. Among the possible reasons for the discrepancies found, we suggest that the time required to taxidermize trophy specimens may delay the items being addressed to their final destination, in addition to the dual citizenship of some hunters that should also have some influence on our results, as well as the important commercial destination of Brussels Airport. The USA show the highest absolute number of trophy hunters, followed by Spain, but Denmark is the highest driver per capita. Therefore, greater participation of these countries in conservation policies for endangered species is necessary. Additionally, a more detailed differentiation of the term “trophy” to more specific terms such as claws, skins, skulls, etc. may improve reporting systems to easier identify illegal activities related to hunting.     

Forest cover,hunting pressure,and fruit availability influence seed dispersal in a forest‐savanna mosaic in the Congo Basin

Forest fragmentation, reduced forest cover, and hunting pressure are the main threats affecting animal‐mediated seed dispersal. However, their combined effects on seed dispersal rates have been simultaneously investigated only rarely, and never in Africa. We aimed to disentangle the effects of forest cover, hunting pressure, frugivore abundance, and fruit availability at the local and landscape scales on the seed dispersal rates of Staudtia kamerunensis (Myristicaceae). To estimate the percentages of seed dispersal failure (undispersed seeds), we quantitated fruit remains below fruiting trees distributed across five contrasting sites in a semi‐natural forest‐savanna mosaic in the Democratic Republic of Congo. We used statistical analyses accounting for spatial autocorrelation and found that forest cover in the surrounding landscape, hunting level, the associated abundance of dispersers, and fruit availability all had significant effects on the percentage of seed dispersal failure. The combination of high fruit availability and reduced abundance of seed dispersers could accelerate seed disperser satiation, causing the seed dispersal system to be saturated. Our study highlights how two major factors associated with anthropogenic activities, forest cover and hunting, affect seed dispersal by animals. These findings could have far‐reaching implications for our understanding of tree‐frugivore interactions and the conservation of tropical communities.     

The phenotype and genotype of rheumatoid arthritis in the Democratic Republic of Congo

Introduction

Little is known about rheumatoid arthritis in the black, particularly in Congolese, populations. Our objective was to describe the phenotype and genotype of rheumatoid arthritis (RA) in Congolese.

Methods

All consecutive rheumatoid arthritis (RA) patients attending Kinshasa University Hospital in a three-year time period were included. Demographics, clinical features and tobacco consumption were noted. Disease Activity Score (DAS)-28 based on the erythrocyte sedimentation rate (ESR), Health Assessment Questionnaire (HAQ), anti-citrullinated peptide antibodies (CCP) antibodies and rheumatoid factor (RF) were determined. Radiographs were scored according to Sharp-van der Heijde. On a subset of patients and controls HLA-DRB1 typing was performed.

Results

A total of 114 females and 14 males aged 51.2 ± 14.9 were included. Mean duration of symptoms was four years. Moderate tobacco consumption was reported in a minority of patients. DAS-28 at first visit was >5.1 and HAQ ≥0.5 in all patients. X-rays showed joint erosions and/or joint space narrowing, mostly of a moderate grade in 55.8% of patients. Anti-CCP and/or RF were present in 48.6% of patients with available data (n = 72) and in 3.0% of controls (n = 67). Radiographic changes and nodules were more frequent in RF or anti-CCP positive patients. One copy of the shared epitope was found in 13 patients (35.1%) and 3 controls (12.5%). Two copies were found in one patient (2.7%) and in one control (4.2%).

Conclusion

Congolese patients with RA consult long after disease onset. Despite this delay, the majority presents without major damage and is RF, anti-CCP and SE negative. We put forward the hypothesis that besides different environmental factors there is probably also a particular genetic risk profile in Congolese patients, different from the HLA-DRB1 shared epitope.     

Nutrient dynamics throughout the rotation of Eucalyptus clonal stands in Congo

The dynamics of the main nutrient fluxes of the biological cycle were quantified in a clonal Eucalyptus plantation throughout the whole planted crop rotation: current annual requirements of nutrients, uptake from the soil, internal translocations within trees, return to soil (litterfall and crown leaching) and decomposition in the forest floor. As reported for other species, two growth periods were identified in these short-rotation plantations: (1) a juvenile phase up to canopy closure, during which the uptake of nutrients from the soil reserves supplied most of the current requirements; and (2) a second phase up to harvest, characterized by intense nutrient recycling processes. Internal translocation within trees supplied about 30 % of the annual requirements of N and P from 2 years of age onwards, and about 50 % of the K requirement. The mineralization of large amounts of organic matter returned to the soil with litterfall during stand development represented a key process providing nutrients to the stand at the end of the rotation. The importance of the recycling processes was clearly shown by the small amounts of nutrients permanently immobilized in the ligneous components of trees, compared with the total requirements accumulated over the stand rotation which were two to four times higher. Small pools of nutrients circulating quickly in the ecosystem made it possible to produce high amounts of biomass in poor soils. The sustainability of these plantations will require fertilizer inputs that match the changes in soil fertility over successive rotations, mainly linked to the dynamics of organic matter in this tropical soil.     

Optimization theory and pre-columbian hunting in the Tehuacan Valley

Previous analyses of faunal remains from highland Mesoamerican sites have viewed implied changes in animal exploitation patterns as a secondary consequence of early agricultural practices. This paper argues that faunal data from the Tehuacan Valley, when interpreted within an optimization framework provide evidence for the alteration of optimal meat harvesting strategies through time by communities responding to a variety of socioenvironmental factors: seasonal and long-term availability of game, access to domestic meat resources, human meat demand levels, and scheduling constraints.     

Subsistence hunting and bushmeat exploitation in central-western Tanzania

An ethnozoological research was carried out in the Tabora District (central-western Tanzania) from December '95 to February '96, to gather information on the sustainable exploitation of wildlife there and to outline the zoological culture of the native people (the Banyamwezi). The objective was to describe the hunting activity and the techniques employed in capturing wild mammals and to gather quantitative data on game harvest. An inventory of the mammal species living in the study area was conducted by three different methods: (1) direct field observation of animals and their tracks; (2) identification of animals captured by the villagers; (3) interviews with the hunters. The activities of 10 local hunters from seven villages were followed during a nine week period. The number of mammals killed and the techniques used for each species were recorded. Other data were collected through interviews of the villagers and concerned (1) the use of every species as food or for other purposes; (2) the species considered as pests; (3) the best places and time for hunting the different species; (4) the time spent hunting them; (5) the food restrictions and taboos; (6) the extent of the bushmeat market (quantity, price, etc.). A total of 236 animals belonging to 37 species were killed during the study period with the following breakdown into taxonomic groups: Bovidae (44.06%), Carnivora (22.88%), Lagomorpha (8.05%), Rodentia (7.2%), diurnal Primates (5.93%), Insectivora (4.23%), Hyracoidea (0.84%), nocturnal Primates (0.84%), Hippopotamidae (0.42%) and Pholidota (0.42%). Four different techniques were used by local hunters in the study area: guns (53.81%), traps (19.06%), spears (11.01%) and dogs (16.01%). Poaching is rampant because of the scarcity of ranger staff and vehicles for patrolling.     

Reductions in primate abundance and diversity in a multiuse protected area: synergistic impacts of hunting and logging in a congo basin forest

This article explores spatial and temporal changes in diurnal primate abundance and behavior in response to hunting, logging, and conservation at the Dzanga Sangha Dense Forest Reserve (RDS), Central African Republic over time. We use a combination of line-transect surveys in 2002 and 2009 (N = 540 km) and ethnographic interviews (N = 210) to investigate changes in the status of cercopithecines and colobines at RDS, with additional comparisons to earlier work. This protected area was lightly logged in the 1970s and the park was gazetted in 1990, with multiple-use reserve sectors allocated. Since the park's inception, hunting and the trade of primates have increased, along with human migration, greater accessibility of arms, and reduction of preferred ungulate prey. Primates have declined in both the park and reserve sectors. Our data further suggest that at RDS hunting has had a greater impact on primate diversity and abundance than logging. We have identified changes in species-specific vulnerability to hunting over time, with Cercopithecus nictitans and Lophocebus albigena initially having appeared to be relatively resistant to hunting pressure in 2002. However, subsequently as gun hunting has increased at RDS, these species have become vulnerable. Although monkeys at RDS have been responding behaviorally to increased gun hunting, they are not able to keep pace with changing hunting practices. This study allows us to begin to understand synergistic impacts of hunting and logging, necessary if we are to recommend strategies to better secure the future of primates in multiuse protected areas.     

Recovery of saltwater crocodiles following unregulated hunting in tidal rivers of the Northern Territory,Australia

Saltwater crocodiles (Crocodylus porosus) in the Northern Territory of Australia were protected in 1971, after a severe population decline resulting from 26 yr of intense commercial hunting. By that time wild saltwater crocodiles were rarely sighted anywhere and they were commercially extinct in areas where they had once been abundant. Standardized monitoring by spotlight surveys started in 1975 and provided relative density indices over time (1975–2009) as a unique record of the post-protection recovery of a wild crocodilian population. We examined the survey data for populations at 12 major tidal rivers, individually and as a single subpopulation. The pattern of recovery in the subpopulation in both abundance and biomass was approximated by logistic curves, predicting 5.26 non-hatchling crocodiles weighing 387.64 kg sighted per kilometer of river in 2010. We predicted potential carrying capacity as 5.58 non-hatchling crocodiles (5.73% higher than 2010) weighing 519.0 kg (25.31% higher than 2010). Individual rivers showed largely different abundance and biomass among rivers. The statistical model that best described the recovery in individual rivers was not always logistic. However, where it was logistic, expected carrying capacity of different rivers showed considerable variation in abundance and biomass. The variation indicates different habitat quality among the rivers. Recovery occurred despite various consumptive uses, particularly a widespread egg-harvest program, which has been an integral part of the incentive-driven conservation program for saltwater crocodiles in the Northern Territory since 1983. We suggest that the saltwater crocodile population of the Northern Territory is achieving full recovery from uncontrolled hunting in 1945–1971. Although saltwater crocodiles are considered an important natural resource, their increase in number, size, and distribution is posing management issues for public safety. Continuation of human–crocodile conflict management through public education and strategic removal of problem crocodiles will be essential. © 2011 The Wildlife Society.     

Small pack size imposes a trade-off between hunting and pup-guarding in the painted hunting dog Lycaon pictus

The painted hunting dog or African wild dog, Lycaon pictus,is one of the most endangered large carnivores in Africa, withextinction predicted within a few decades if their dramaticdecline is not stopped. It has recently been hypothesized thatbecause of their constraining need for helpers, group sizewas of major importance in obligate cooperative breeding species,and that the resulting likely existence of a threshold numberof adults could create an Allee effect, increasing the groupextinction risk. One example where the importance for a criticalnumber of adults may have major repercussions for painted huntingdogs concerns baby-sitting, or pup-guarding, a behavior typicalof obligate cooperative breeders. We propose that, as forgoingthis behavior is costly because pup guards have the potentialto decrease pup mortality, its use is costly too, especiallyin small packs, because helpers are strongly needed for theircooperative foraging (hunting, protecting the kill and bringingback food to the pups). We present a simple model showing howpup-guarding imposes a cost because it implies that less foodper hunt is brought back to more individuals at the den. Wecomplete these analyses with empirical tests of the effectof pack size on the probability of pup-guarding, from fielddata from the Hwange population in Zimbabwe. Our model, aswell as our 5 years of empirical data, both suggest a criticalthreshold at a size of about five individuals.     

Densities,Distributions, and Seasonal Movements of Gorillas and Chimpanzees in Swamp Forest in Northern Congo

The conservation of gorillas (Gorilla spp.) and chimpanzees (Pan troglodytes) depends upon knowledge of their densities and distribution throughout their ranges. However, information about ape populations in swamp forests is scarce. Here we build on current knowledge of ape populations by conducting line transect surveys of nests throughout a reserve dominated by swamp forest: the Lac Télé Community Reserve in northern Congo. We estimated gorilla and chimpanzee densities, distributions across habitats, and seasonal changes in abundance. Gorilla density was 2.9 gorillas km^–2, but densities varied by habitat (0.3–5.4 gorillas km^–2) with highest densities in swamp forest and terra firma mixed forest. Average chimpanzee density is 0.7 chimpanzees km^–2 (0.1–1.3 chimpanzees km^–2), with highest densities in swamp forest. Habitat was the best predictor of ape nest abundance, as neither the number of human indices nor the distance from the nearest village predicted nest abundance. We recorded significantly greater numbers of apes in terra firma forest during the high-water season than the low-water season, indicating that many gorillas and chimpanzees are at times concentrated in terra firma forest amid a matrix of swamp forest. Seasonally high numbers of apes on terra firma forest islands easily accessible to local people may expose them to substantial hunting pressure. Conversely, the nearly impenetrable nature of swamp forests and their low value for logging makes them promising sites for the conservation of apes.     

Subsistence productivity and hunting effort in native South America

The question of why people work more or less at various activities is an old one in anthropology and recently has surfaced in studies of native South American societies. Growing out of debates about protein scarcity, arguments have arisen over the reasons why people spend time on hunting and fishing. Some authors suggest that labor allocation and other societal features can be explained with reference to absolute minimum requirements for specific nutrients (e.g., protein). This study presents data from four native Central Brazilian societies on the time spent at various subsistence tasks and the productivity of those tasks. The evidence suggests that decisions to allocate labor to hunting and fishing are influenced more by the overall possibilities for production in an area than by the availability of animal proteins alone. Satisfaction of calorie requirements appears to take precedence over satisfaction of protein requirements. In those societies in which gardening is highly productive, people can spend more time on hunting and fishing and improve the overall quality of their diet.     

Directional preference may enhance hunting accuracy in foraging foxes

Red foxes hunting small animals show a specific behaviour known as 'mousing'. The fox jumps high, so that it surprises its prey from above. Hearing seems to be the primary sense for precise prey location in high vegetation or under snow where it cannot be detected with visual cues. A fox preparing for the jump displays a high degree of auditory attention. Foxes on the prowl tend to direct their jumps in a roughly north-eastern compass direction. When foxes are hunting in high vegetation and under snow cover, successful attacks are tightly clustered to the north, while attacks in other directions are largely unsuccessful. The direction of attacks was independent of time of day, season of the year, cloud cover and wind direction. We suggest that this directional preference represents a case of magnetic alignment and enhances the precision of hunting attacks.     

Primate and ungulate abundance in response to multi‐use zoning and human extractive activities in a Central African Reserve

This study examines the abundance of key mammal species at the Dzanga‐Sangha Reserve (RDS) in the Central African Republic with respect to conservation zoning and human activities in the reserve. RDS has been funded as an integrated conservation and development project since the mid‐1980s. This study illustrates distinct wildlife responses to logging and hunting in RDS sectors that vary in protection and enforcement levels and the erosion of some critical animal communities across the RDS in the face of challenges of increasing human populations and flows of arms and ammunitions there. Our results show elephants (Loxodonta africana cyclotis) to be appreciably absent close to human settlements, and increasingly vulnerable to hunting in the more integrally protected sectors far from town. We have found that duikers (Cephalophus sp.) and western lowland gorillas (Gorilla g. gorilla) make use of recently logged areas but are vulnerable to hunting there. These species are now most abundant farthest from human settlements. Our results have implications for the formulation of adaptive management plans that would benefit from the inclusion of nuanced understandings of site‐specific and species‐specific responses to microhabitats and the particular kinds of human extractive activities and challenges in the region.     

Linking anti‐predator behaviour to prey demography reveals limited risk effects of an actively hunting large carnivore

Ecological theory predicts that the diffuse risk cues generated by wide‐ranging, active predators should induce prey behavioural responses but not major, population‐ or community‐level consequences. We evaluated the non‐consumptive effects (NCEs) of an active predator, the grey wolf (Canis lupus), by simultaneously tracking wolves and the behaviour, body fat, and pregnancy of elk (Cervus elaphus), their primary prey in the Greater Yellowstone Ecosystem. When wolves approached within 1 km, elk increased their rates of movement, displacement and vigilance. Even in high‐risk areas, however, these encounters occurred only once every 9 days. Ultimately, despite 20‐fold variation in the frequency of encounters between wolves and individual elk, the risk of predation was not associated with elk body fat or pregnancy. Our findings suggest that the ecological consequences of actively hunting large carnivores, such as the wolf, are more likely transmitted by consumptive effects on prey survival than NCEs on prey behaviour.