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1.
Hunting and trade of wild animals for their meat (bushmeat), especially mammals, is commonplace in tropical forests worldwide. In West and Central Africa, bushmeat extraction has increased substantially during recent decades. Currently, such levels of hunting pose a major threat to native wildlife. In this paper, we compiled published data on hunting offtake of mammals, from a number of studies conducted between 1990 and 2007 in Cameroon, Central African Republic, Democratic Republic of Congo, Equatorial Guinea, Gabon, and Republic of Congo. From these data sources, we estimated annual extraction rates of all hunted species and analyzed the relationship between environmental and anthropogenic variables surrounding each hunting rate and levels of bushmeat extraction. We defined hunting pressure as a function of bushmeat offtake and number of hunted species and confirm that hunting pressure is significantly correlated with road density, distance to protected areas and population density. These correlations are then used to map hunting pressure across the Congo Basin. We show that predicted risk areas show a patchy distribution throughout the study region and that many protected areas are located in high‐risk areas. We suggest that such a map can be used to identify areas of greatest impact of hunting to guide large‐scale conservation planning initiatives for central Africa.  相似文献   

2.
Unsustainable hunting is a threat to conservation and rural livelihoods that depend on bushmeat for food and income. To reduce the pressure on forest-dependent vulnerable species, hunting in farmland might complement offtake from forests and provide a sustainable source of bushmeat. To explore this possibility, we investigated patterns of hunting and wildlife depletion, and integration of hunting into agricultural livelihoods, in an intensively managed farm-forest mosaic landscape. Surveys were conducted across 63 households over a year in a Ghanaian cocoa-farming community surrounded by a timber production forest. The findings indicated a high level of wildlife depletion in the landscape and the local extinction of the largest species, especially in farmland. Most hunting occurred in forests and offtake from farmland was low, yet hunting in farmland was disproportionately common relative to its coverage in the landscape. Most farmland hunting was opportunistic and integrated with agricultural activities. Our findings suggest that intensively used farmland provides little opportunity to reduce hunting pressure in forests.  相似文献   

3.
In 1992, tourist hunting in the Selous Game Reserve generated 1.28 million dollars for the Tanzanian government, of which 0·96 million dollars were returned to wildlife conservation. Lions ( Panthera leo ) are one of three critical species for tourist hunting, consistently generating 12%–13% of hunting revenue from 1988 to 1992. Because of their ecological and economic importance (and intrinsic value), it is important that lion quotas be set so that offtake is sustainable. The population density of lions in Selous ranges from 0·08 to 0·13 adults km−2, comparable to unhunted ecosystems. The adult sex ratio (36–41% male) and the ratio of cubs to adults (29% cubs) are similar to those of unhunted populations. The ratio of lions to hyaenas is lower in heavily hunted areas (0·17 lions/hyena) than in unhunted areas (0·43 lions/hyena). Hunting levels between 1989 and 1994 took 2·7–4·3% of adult males annually, which is sustainable. The current quota is 10–16% of the adult male population, which exceeds natural mortality rates for male lions. To remain stable if the quota was filled, the population would have to compensate via increased fecundity, increased juvenile survival, or an altered sex‐ratio. Compensation occurs in Selous by producing (or raising) more male than female cubs (66–81% of juveniles are male). Only 28% of the Selous quota was filled in 1992. The percentage of quota filled (both in Selous and nationwide) has dropped since 1988 as quotas have increased. The current intensity of lion hunting in Selous is sustainable, but the quota cannot be filled sustainably.  相似文献   

4.
We examined the effects of protection from human activities and effects of tourist hunting on densities of 21 large mammal species in Tanzania. Aerial censuses revealed that mammal biomass per km2 was highest in National Parks. Densities of nine ungulate species were significantly higher in National Parks and Game Reserves than in areas that permitted settlement; these tended to be the larger species favoured by poachers. The presence of tourist hunters had little positive or negative impact on ungulate densities, even for sought-after trophy species; limited ground censuses confirmed these results. Our analyses suggest that prohibition of human activity, backed up by on-site enforcement, maintains ungulate populations at relatively high densities, and challenge the idea that enforcement is only effective when spending is high.  相似文献   

5.
A considerable proportion of tropical protected areas are Sustainable Use Reserves (SURs), where socio-biodiversity protection and sustainable resource extraction are the main goals. Subsistence hunting is the most widespread form of subcanopy forest resource extraction, and often depletes game populations within SURs, but the degree to which these extractive activities are sustainable remains questionable. To assess patterns of hunting sustainability within SURs, we systematically examined the local ecological knowledge of 211 resident hunters living in 93 communities located within and immediately outside nine SURs of Brazilian Amazonia. We used mixed models to assess the effects of settlement features (distance to reserve boundaries, size, age, distance to urban centers, and extent of floodplain areas) on local perceptions of game abundance, the prey profile of the most consumed game species, and overall levels of local game depletion. Hunters consistently reported that game populations were less impacted within communal catchment areas containing larger amounts of floodplain habitat and farther from urban centers. In these areas the overall game abundance was perceived to be higher, low-fecundity species were most consumed, and harvest-sensitive species were least depleted. Local SUR communities within this context accrued higher benefits from higher wild-meat availability, but settlement age and size had no effects on hunted species. Evidence-based conservation management plans in tropical protected areas should focus on reducing wild meat demand in urban areas and managing both, the local aquatic animal protein in floodplain areas to relieve pressure on terrestrial game species, and the offtake of game populations at inland sites lacking access to aquatic animal protein.  相似文献   

6.
Cost–benefit considerations of wildlife monitoring are essential, particularly, in areas outside national park boundaries, where resources for conducting wildlife censuses are scarce, but that, at the same time, are subject to high pressure for wildlife utilization, such as hunting. Large mammal survey data from various sources were collated and analyzed to investigate which methods are best suited for monitoring purposes at low cost in the Tarangire–Manyara ecosystem, northern Tanzania. Our results indicate that primary data (from aerial and road transects counts) that involve direct species observations, although sometimes very expensive, are required for establishing the status of the target species in terms of density or population size. Concomitantly, secondary data from various sources, such as interviews, hunting quota, and damage reports, obtained over wide areas and over longer periods of time, can provide important information on presence/absence and distribution of species within an area. In addition, the study revealed that hunting quotas set did not correlate with species abundance/numbers from the primary data surveys for most of the large mammals hunted within the ecosystem. For a better conservation and management of wildlife, in particular with respect to the forthcoming formation of Wildlife Management Areas, we propose an integrated approach to wildlife monitoring using primary and secondary data sources through the involvement of local people’s knowledge.  相似文献   

7.
Sustainable legal subsistence hunting has a place in conservation. Nonetheless, the long-term success of such schemes depends on them being well managed. We assessed the effectiveness of legal subsistence hunting in the Ugalla ecosystem of western Tanzania using data from the local legal hunting scheme. The hunting in the ecosystem is conducted within the partially protected areas around Ugalla Game Reserve. The Wildlife Division of Tanzania supervises hunting activities in the area via local conservation authorities. We analysed hunting success (animals shot per quota per licence) across species in the period from 1997 to 2004. Our results revealed that 10,511 and 5,991 animals were licenced and shot, respectively. There were considerable variations in hunting success across wildlife species. With the exception of common duiker (Sylvicapra grimmia), hunting success trends for most of the species were declining. The documented decline in wildlife off-take should be further investigated to ensure the sustainable management of this area.  相似文献   

8.
Prey preferences of top carnivores in African ecosystems are well known, but far less is understood about the preferences of human hunters and the effects of their hunting activities. We interviewed 82 hunters living in Mpimbwe Division adjacent to Katavi National Park and Rukwa Game Reserve in western Tanzania. We compared stated preferences for different species of mammals with that reportedly hunted, and we used reportedly hunted species in Jacob's indices to examine proportional offtake of each species that would be expected as based on both encounters and density estimates of the wildlife species. Then, using general linear models, we tested whether the derived indices of preference were affected by the proportional density, habitat preference, and body mass of the mammalian prey species. We found that hunters would like to kill large mammals but, instead, hunt opportunistically when they cannot realize these preferences and so end up taking smaller species than would be expected. We found that a surprising amount of rarer species is taken in this ecosystem. Our study helps to unveil novel information that wildlife managers can use to predict what hunters take most from protected areas, and it highlights the importance of treating humans as apex predators in modern day Africa.  相似文献   

9.
Subsistence hunting has been a vital activity for local people across Neotropical rain forests (NRF). While providing a reliable source of protein, subsistence hunting also reflected the strong relationships that connected local people with the species and ecosystems in which they inhabited. However, the social and ecological context in which subsistence hunting can be sustainable has been altered. The relatively small groups that hunted in large and mostly undisturbed forests, using traditional weapons, have been replaced by a growing population using fragmented habitats and modern hunting methods. Thus, subsistence hunting is less likely to be sustainable, threatening the food security of local people and the persistence of species with critical roles in the functioning of NRF. Managing subsistence hunting in this changing context will require a more efficient combination of tools which might include banning the hunting of large and sensitive species, strengthening protected areas, alternatives to reduce the role of wildlife protein on local people's subsistence and, in some cases, voluntary resettlements of local people, from areas that could still be used as refuge for endangered species.  相似文献   

10.
Following the growth and geographic expansion of wolf (Canis lupus) populations reintroduced to Yellowstone National Park and central Idaho in 1995–1996, Rocky Mountain wolves were removed from the endangered species list in May 2009. Idaho and Montana immediately established hunting seasons with quotas equaling 20% of the regional wolf population. Combining hunting with predator control, 37.1% of Montana and Idaho wolves were killed in the year of delisting. Hunting and predator control are well-established methods to broaden societal acceptance of large carnivores, but it is unprecedented for a species to move so rapidly from protection under the Endangered Species Act to heavy direct harvest, and it is important to use all available data to assess the likely consequences of these changes in policy. For wolves, it is widely argued that human offtake has little effect on total mortality rates, so that a harvest of 28–50% per year can be sustained. Using previously published data from 21 North American wolf populations, we related total annual mortality and population growth to annual human offtake. Contrary to current conventional wisdom, there was a strong association between human offtake and total mortality rates across North American wolf populations. Human offtake was associated with a strongly additive or super-additive increase in total mortality. Population growth declined as human offtake increased, even at low rates of offtake. Finally, wolf populations declined with harvests substantially lower than the thresholds identified in current state and federal policies. These results should help to inform management of Rocky Mountain wolves.  相似文献   

11.
Wild animals are a primary source of protein (bushmeat) for people living in or near tropical forests. Ideally, the effect of bushmeat harvests should be monitored closely by making regular estimates of offtake rate and size of stock available for exploitation. However, in practice, this is possible in very few situations because it requires both of these aspects to be readily measurable, and even in the best case, entails very considerable time and effort. As alternative, in this study, we use high-resolution, environmental favorability models for terrestrial mammals (N = 165) in Central Africa to map areas of high species richness (hot spots) and hunting susceptibility. Favorability models distinguish localities with environmental conditions that favor the species'' existence from those with detrimental characteristics for its presence. We develop an index for assessing Potential Hunting Sustainability (PHS) of each species based on their ecological characteristics (population density, habitat breadth, rarity and vulnerability), weighted according to restrictive and permissive assumptions of how species'' characteristics are combined. Species are classified into five main hunting sustainability classes using fuzzy logic. Using the accumulated favorability values of all species, and their PHS values, we finally identify weak spots, defined as high diversity regions of especial hunting vulnerability for wildlife, as well as strong spots, defined as high diversity areas of high hunting sustainability potential. Our study uses relatively simple models that employ easily obtainable data of a species'' ecological characteristics to assess the impacts of hunting in tropical regions. It provides information for management by charting the geography of where species are more or less likely to be at risk of extinction from hunting.  相似文献   

12.
What determines the vulnerability of protected areas, a fundamental component of biodiversity conservation, to political instability and warfare? We investigated the efficacy of park protection at Garamba National Park (Democratic Republic of Congo) before, during and after a period of armed conflict. Previous analysis has shown that bushmeat hunting in the park increased fivefold during the conflict, but then declined, in conjunction with changes in the sociopolitical structures (social institutions) that controlled the local bushmeat trade. We used park patrol records to investigate whether these changes were facilitated by a disruption to anti-poaching patrols. Contrary to expectation, anti-poaching patrols remained frequent during the conflict (as bushmeat offtake increased) and decreased afterwards (when bushmeat hunting also declined). These results indicate that bushmeat extraction was determined primarily by the social institutions. Although we found a demonstrable effect of anti-poaching patrols on hunting pressure, even a fourfold increase in patrol frequency would have been insufficient to cope with wartime poaching levels. Thus, anti-poaching patrols alone may not always be the most cost-effective means of managing protected areas, and protected-area efficacy might be enhanced by also working with those institutions that already play a role in regulating local natural-resource use.  相似文献   

13.
The impact of unsustainable land-use conversions, changes in climate and anthropogenic activities on abundance and distribution of baobab populations was assessed in semi-arid regions of Tanzania. Baobabs were sampled in plots of 1 km long and a 50 m wide, which were carried out in 337 grids located in different land-use types. Transects for each land-use type were located using a stratified random sampling technique to compare baobab population variations and occurrences in semi-arid areas of Tanzania. Baobab density was found to be highest in strictly protected areas and the lowest density in unprotected areas, suggesting that anthropogenic activities coupled with local management practices within land-uses may be influencing its viability in semi-arid areas. In species like this, with less and slow recruitment rate, it takes a long time to bring the population to recovery when substantial disturbance and overutilisation have reduced the populations to certain levels. Thus, increased human and climate change pressures on land are likely to drive the species to extinction in these fragmented populations.  相似文献   

14.
Although being an important conservation tool in Africa, trophy hunting is known to influence risk perception in wildlife species, thus affecting the behaviour and fitness of most targeted species. We studied the effects of trophy hunting on the flight behaviour of impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in two closed ecosystems, Cawston Ranch (hunting area) and Stanley and Livingstone Private Game Reserve (tourist area), western Zimbabwe. Using standardized field procedures, we assessed the flight behavioural responses of the three species in two seasons: non‐hunting (December–March) and hunting (April–November) between March 2013 and November 2014. We tested the effect of habitat, group size, sex, season, start distance and alert distance on flight initiation distance using linear mixed models. Habitat, group size sex and alert distance did not have any effect on flight initiation distance for the three species. The three species were more alert and displayed longer flight initiation distances in the hunting area compared with the tourist area. Flight initiation distances for the three species were higher during the hunting season for the hunting area and low during the non‐hunting season. Flight distances of the three species did not differ between the hunting area and the tourist area. We concluded that trophy hunting increased perceived risk of wild ungulates in closed hunting areas, whereas ungulates in non‐hunting areas are less responsive and somehow habituated to human presence. Management plans should include minimum approach distances by tourists as well as establishing seasonal restrictions on special zones to promote species viability. Research aimed at integrating behavioural responses with physiological aspects of target species should be promoted to ensure that managers are able to deal with the behavioural trade‐offs of trophy hunting at local and regional scale.  相似文献   

15.
The brown bear (Ursus arctos) in Croatia is currently being managed through trophy hunting, with quotas allocated to local hunting organisations. Human–bear conflict is present at a low level, but any losses are compensated by the hunting organisations that benefit from bear hunting. Attitudes towards bears are generally positive, and the bear population appears stable, or even increasing. Croatia's current bear hunting policy relies upon both the ecological sustainability of the quotas and the economic sustainability of the hunting organisations. To address the first of these pillars of current policy, we used a two-sex matrix model of the bear population to investigate the biological sustainability of current hunting levels. The model suggests that if the annual allocated quota were fully realised, the population would suffer a considerable decrease over 10 years. A likely explanation for the mismatch between this result and the observed stability of the population is that the bear population size is underestimated. To address the second pillar, we quantified the current structure, costs and benefits of bear hunting to hunting organisations through an interview survey with hunting managers. We found that bear hunting is a substantial component of hunting organisations' income, supporting the other activities of the organisation. Croatia's recent accession to the EU will require changes in their bear management system, potentially stopping bear trophy hunting. Therefore, we assessed the changes in hunting organisations' budgets in the absence of bear hunting. Our results demonstrate that a loss of bear trophy hunting would result in a substantial loss of income to the hunting organisations. Moving bear hunting and compensation mechanisms from local management and responsibility to a more centralised system without trophy hunting, as suggested by EU legislation, will lead to considerable uncertainties. These include how to make centralised decisions on population targets and offtake levels for population control, given the uncertainty around population estimates, and on compensation payments given the loss of the current system which relies heavily on local income from trophy hunting, local relationships and informal monetary and non-monetary compensation.  相似文献   

16.
Bushmeat hunting is threatening wildlife populations across west-central Africa, and now poses a greater threat to primates than habitat loss or degradation does in some areas. However, species vary in their abilities to withstand hunting, either because hunters target them differentially or they vary in their vulnerability to a given level of hunting. We studied the impact of current levels of gun-hunting on diurnal primate species in the little-studied Monte Mitra area of Monte Alén National Park, continental Equatorial Guinea. Most bushmeat is currently trapped, but gun-hunting is increasing as shotguns become more available and affordable, allowing targeting of arboreal as well as terrestrial prey. We collected data over 15-mo, via hunter interviews, gun-hunter follows, an offtake survey recording 9374 individuals, and primate surveys covering 408 km of line transects in 2 sites with differing gun-hunting histories. Inside the park, where gun-hunting pressure was recent and light, we found high primate diversity, density, and biomass, with black colobus (Colobus satanas) particularly abundant at 57 individuals/km2. However, around the village, where gun-hunting was longer-established, though other species such as the guenons still persisted (albeit at lower densities), Colobus satanas were virtually absent. Being slow and large-bodied, Colobus satanas are preferred and susceptible prey, and an early indicator of overhunting. Monte Alén National Park is currently an important stronghold for primates, particularly Colobus satanas, but regulation of the trade and enforcement of hunting bans in the park are urgently needed to safeguard their future and that of other vulnerable species. An erratum to this article can be found at  相似文献   

17.
1. In Africa the majority of conservation areas sanction some sort of human activities within their borders but few of them are part of community-based conservation schemes. The effectiveness of these state-owned, partially protected areas in conserving mammalian fauna is largely unknown.
2. Large and medium-sized mammal densities in three different sorts of partially protected area were compared to mammal densities in an adjacent national park in western Tanzania by driving 2953 km of strip transects over a 14-month period.
3. In a Game Controlled Area that permitted temporary settlement, cattle grazing and tourist big game hunting, mammal diversity and mammal densities were relatively high. In a Forest Reserve that permitted limited hardwood extraction and resident hunting, most large species were absent. In a third, Open Area that allowed settlement, cattle grazing, firewood collection and beekeeping activities, mammal diversity and densities were again low but some large ungulates still used the area seasonally.
4. The chief factors responsible for lowered mammal densities outside the Park were illegal hunting, especially in close proximity to town, and to a lesser extent, resident hunting quotas that were too high.
5. These data suggest that state-owned conservation areas permitting human activities within their borders cannot be relied upon as a means of conserving large and middle-sized mammals in Africa.
6. Two methods are being employed to ameliorate this problem in Africa: excluding people from conservation areas while upgrading ground protection effort, and initiation of community-based conservation schemes. As yet, however, very few quantitative data are available to evaluate the efficacy of these methods in enhancing mammal populations.  相似文献   

18.
The blue duiker (Philantomba monticola) is an abundant and widely distributed ungulate in continental sub‐Saharan Africa. High hunting pressure throughout its range may be particularly threatening to the persistence of island populations of the species. In this study, we assessed offtake of blue duikers in Pico Basilé, Bioko Island, Equatorial Guinea. We recorded the number of animals shot or snared by 46 commercial hunters over a 33‐month period, and the location (elevation) of each animal hunted. From this, we estimated catch per hunter (CH), catch per hunting day (CD) and catch per unit effort (CPUE). The number of duikers shot or snared across the study period, significantly declined within the mid‐altitude range (901–1500 m). There were no significant drops in CH or CPUE at low or high altitudes for snared animals. The ratio of immature‐to‐adult animals hunted increased significantly over time within the mid‐altitude range. We suggest that these trends in offtake, especially in the more heavily hunted mid‐altitudes of the study area, indicate a decline in the population within this range. If this situation is widespread throughout the island, it is likely that unregulated bushmeat hunting will have devastating consequences to the biodiversity of Bioko Island, particularly for heavily hunted species that are naturally less abundant.  相似文献   

19.
Recent studies indicate that trophy hunting is impacting negatively on some lion populations, notably in Tanzania. In 2004 there was a proposal to list lions on CITES Appendix I and in 2011 animal-welfare groups petitioned the United States government to list lions as endangered under their Endangered Species Act. Such listings would likely curtail the trophy hunting of lions by limiting the import of lion trophies. Concurrent efforts are underway to encourage the European Union to ban lion trophy imports. We assessed the significance of lions to the financial viability of trophy hunting across five countries to help determine the financial impact and advisability of the proposed trade restrictions. Lion hunts attract the highest mean prices (US$24,000-US$71,000) of all trophy species. Lions generate 5-17% of gross trophy hunting income on national levels, the proportional significance highest in Mozambique, Tanzania, and Zambia. If lion hunting was effectively precluded, trophy hunting could potentially become financially unviable across at least 59,538 km(2) that could result in a concomitant loss of habitat. However, the loss of lion hunting could have other potentially broader negative impacts including reduction of competitiveness of wildlife-based land uses relative to ecologically unfavourable alternatives. Restrictions on lion hunting may also reduce tolerance for the species among communities where local people benefit from trophy hunting, and may reduce funds available for anti-poaching. If lion off-takes were reduced to recommended maximums (0.5/1000 km(2)), the loss of viability and reduction in profitability would be much lower than if lion hunting was stopped altogether (7,005 km(2)). We recommend that interventions focus on reducing off-takes to sustainable levels, implementing age-based regulations and improving governance of trophy hunting. Such measures could ensure sustainability, while retaining incentives for the conservation of lions and their habitat from hunting.  相似文献   

20.
To assess the effect of on-going and of previous or near by hunting pressure on game birds in a neotropical rain forest (French Guiana), I compared species abundances between six hunted and disturbed areas, seven non-hunted and pristine areas and eight intermediate areas, undisturbed and not currently hunted, but formerly hunted or close to current hunting areas. I recorded all birds detected within 100 m-wide strip transects, walked at random through every forest type all day long. The frequency of records per 10 h and flock sizes on each transect were averaged over all surveys in each study site (N = 3025 h). Censused groups included terrestrial (tinamous, woodquails, curassow and trumpeter) and arboreal species (guans, macaws, parrots, toucans), but not waterbirds. The abundance of all game birds was higher in non-hunted than in hunted areas, though not always significantly for secretive understorey species (tinamous, guans, wood-quail) or canopy frugivores (parrots, macaws, toucans). The Black Curassow and Gray-winged Trumpeter exhibited the highest and most consistent increases (7–10-fold) and more so between intermediate and non-hunted sites than between hunted and intermediate sites. The mean flock size also increased along the hunting gradient, especially in flocking species (macaws, parrots, trumpeter). Low reproductive rates and/or seasonal movements may explain that hunting pressure could still be felt after hunting has ceased or when it persists only away from a given area. Such a persistent effect would affect some populations in small protected areas.  相似文献   

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