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.     

Trophy hunting and perceived risk in closed ecosystems: Flight behaviour of three gregarious African ungulates in a semi‐arid tropical savanna

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.     

Evolutionary and ecological traps for brown bears Ursus arctos in human‐modified landscapes

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Large Mammals in an Agroforestry Mosaic in the Brazilian Atlantic Forest

The forest‐like characteristics of agroforestry systems create a unique opportunity to combine agricultural production with biodiversity conservation in human‐modified tropical landscapes. The cacao‐growing region in southern Bahia, Brazil, encompasses Atlantic forest remnants and large extensions of agroforests, locally known as cabrucas, and harbors several endemic large mammals. Based on the differences between cabrucas and forests, we hypothesized that: (1) non‐native and non‐arboreal mammals are more frequent, whereas exclusively arboreal and hunted mammals are less frequent in cabrucas than forests; (2) the two systems differ in mammal assemblage structure, but not in species richness; and (3) mammal assemblage structure is more variable among cabrucas than forests. We used camera‐traps to sample mammals in nine pairs of cabruca‐forest sites. The high conservation value of agroforests was supported by the presence of species of conservation concern in cabrucas, and similar species richness and composition between forests and cabrucas. Arboreal species were less frequently recorded, however, and a non‐native and a terrestrial species adapted to open environments (Cerdocyon thous) were more frequently recorded in cabrucas. Factors that may overestimate the conservation value of cabrucas are: the high proportion of total forest cover in the study landscape, the impoverishment of large mammal fauna in forest, and uncertainty about the long‐term maintenance of agroforestry systems. Our results highlight the importance of agroforests and forest remnants for providing connectivity in human‐modified tropical forest landscapes, and the importance of controlling hunting and dogs to increase the value of agroforestry mosaics.     

When hunting benefits raptors: a case study of game species and vultures

Management of hunting activity to serve as a tool for sustainable development has become a key issue in conservation biology. However, little evidence is available showing positive impacts of hunting on ecosystem conservation, limiting its capability to be used as a conservation tool. We analysed hunting and its positive influence on the ecology and conservation of the griffon vulture (Gyps fulvus), a scavenger with a relevant function in the ecosystem, in the Cantabrian Mountains, NW Spain. Use of the area by vultures was addressed by looking for cliffs used as roosts or colonies, and consumption of game species by vultures was evaluated through field surveys and questionnaires to hunters. Results revealed a strong spatiotemporal adjustment in the use of the area by vultures and hunting events, especially of red deer and wild boar. Vultures occupied roosting sites very close to the main hunting sectors of these game species and often were seen consuming their carcasses. The spatiotemporal pattern of roost use by vultures strongly overlapped with hunting of red deer. The numbers of both red deer and wild boar hunting episodes within 3.5 km around the roosts were the best predictors of vulture occurrence and number. Our estimates show that hunting could feed around 1,800 vultures/6 months. Hunting can thus influence species at the top of the ecosystem (scavengers) and could aid sustainable management of griffon vulture populations, reconciling hunting and conservation. However, negative and positive impacts should be taken into account simultaneously for an overall evaluation of hunting on ecosystem conservation.     

A pan-neotropical analysis of hunting preferences

Hunting in the neotropics is a widespread form of resource extraction. However, there is increasing concern that current activities are leading to the decline and extirpation of vulnerable species; particulary ateline primates, large ungulates (such as tapirs and white-lipped peccaries) and large birds such as curassows. Hunting patterns are expected to be a product of two principal influences: the value of return for a given amount of effort invested into hunting, and cultural factors that determine the prestige and usefulness of prey. Previous work has suggested that hunting profiles change in a predictable way over time, becoming more diverse and more dependent on smaller bodied species as preferred, large-bodied prey become scarcer. In this paper, we evaluate the hunting profiles of 78 neotropical communities in Central and South America. We investigate the uniformity of species preferences, whether communities that are geographically closer have similar hunting profiles, and whether the age and size of settlements can be used to predict the type and diversity of species targeted. We found that there was only a weak correlation between the structure of communities’ hunting profiles and their geographical proximity. Neither a community’s size nor age was a good predictor of the shape and structure of its hunting profile. Our data suggest that either the availability of prey or the cultural influences dictating the value of different species can change rapidly over small distances, and that older and larger settlements do not impact prey species distributions in a predictable way.     

Hunting,disturbance and roost persistence of bats in caves at Ankarana,northern Madagascar

Surveys and monitoring of 37 caves in and around the Ankarana Special Reserve, northern Madagascar, yielded evidence of hunting of bats and potential disturbance of bats by miners and tourists, and colony counts for several bat species of potential conservation concern. Colony size decreased by 95% and 14% for a colony of Hipposideros commersoni and a colony of Eidolon dupreanum, respectively, when recent evidence of hunting occurred at those colonies and those declines are probably attributable to hunting. Evidence of hunting occurred commonly at the roosts of those species and most commonly at the roosts of Rousettus madagascariensis. Hunting of pteropodids was associated with high vulnerability of roosts to hunters, little forest buffer between the cave and open savannah and the absence of tombs in the cave. Roost sites of the hunted species persisted for at least several years and this regularity may facilitate hunting. This work supports the ranking of E. dupreanum, R. madagascariensis and H. commersoni as species of conservation concern. Managers should consider the impact of tourist visits on bats and of increasing access to caves for tourism. Conservation efforts for the hunted species should also seek to protect vulnerable and unprotected cave roosts.     

Status of diurnal primate populations at the former settlement of a displaced village in Cameroon

To understand whether or not primate populations recover in areas of abandoned human settlements, data are required that allow for site‐specific comparison over time. Here, we present baseline information on the presence/absence and relative abundance of primate species at the abandoned settlement of the Ekundukundu village, relocated out of the Korup National Park in 2000. Between July 2007 and March 2008, 62 km of transects was surveyed for sightings and calls of primates. All eight species of diurnal primates reported in the KNP were confirmed: Cercopithecus nictitans ludio, C. mona, C. erythrotis camerunensis, C. pogonias, Procolobus pennantii preussi, Cercocebus torquatus, Mandrillus leucophaeus leucophaeus, and Pan troglodytes vellerosus. At old Ekundukundu, C. nictitans accounted for 65% of all primate group sightings. Overall, sighting frequency of primates (0.55 groups/km) was not significantly different from other park sectors surveyed by a previous observer (J. Linder) in 2004–2005. The data reported here will be useful in the long‐term monitoring of primate populations in regenerating forest habitats of earlier human settlements. Am. J. Primatol. 72:645–652, 2010. © 2010 Wiley‐Liss, Inc.     

Rapid Assessment of Distribution of Wildlife and Human Activities for Prioritizing Conservation Actions in a Patagonian Landscape

Large landscapes encompassing reserves and areas with other human uses are necessary for conservation of many species. Generating information for conservation planning over such landscapes may be expensive and time-consuming, though resources for conservation are generally limited and conservation is often urgent. We developed a sign-based occupancy survey to help prioritize conservation interventions by simultaneously assessing the distribution of 3 species, the lesser rhea, guanaco, and mara, and their association with human activities in a 20,000-km² landscape in the northern Patagonian steppe. We used a single-season occupancy model with spatial rather than temporal replication of surveys in order to reduce costs of multiple visits to sites. We used covariates related to detectability, environmental factors, and different human activities to identify the most plausible models of occupancy, and calculated importance weights of covariates from these models to evaluate relative impacts of human activities on each species. Abundance of goats had the strongest negative association with lesser rheas and guanacos, and road density with maras. With six months of fieldwork, our results provided initial hypotheses for adaptive conservation interventions for each species. Addressing high livestock densities for rheas and guanacos, poaching by urban hunters for all three species, and hunting by rural people for rheas are priorities for conservation in this landscape. Our methodology provided new insights into the responses of these species, although low detection probabilities for maras indicate that the sampling scheme should be altered for future monitoring of this species. This method may be adapted for any large landscape where a rapid, objective means for prioritizing conservation actions on multiple species is needed and data are scarce.     

Large Mammal Distribution in a Transfrontier Landscape: Trade‐offs Between Resource Availability and Human Disturbance

Understanding factors that affect the persistence of charismatic megafauna in human‐dominated landscapes is crucial to inform conservation decision‐making and reduce human‐wildlife conflict. We assessed the effect of environmental and anthropogenic factors at different landscape and management scales in predicting the distribution of African elephant (Loxodonta africana) within the Greater Mapungubwe Transfrontier Conservation Area in Southern Africa. We combined aerial distribution counts over a 12‐yr period with 14 variables, representing food availability, landscape, and anthropogenic effects, into generalized linear models. Generalized linear models were run for the broader landscape, as well as three separate management units within the broader landscape, namely ecotourism, trophy hunting, and a combination of hunting and ecotourism. Human activities within different management units forced elephant to trade‐off between disturbance avoidance, and good food and water availability. In addition, the important predictors of elephant distribution within each of the management units differed from the predictors at the broader landscape. Overall, our results suggest that at the fine scale, elephant are constraint by factors that may be masked at the broader landscape scale. We suggest that accounting for anthropogenic disturbance is important in determining the distribution of large, wide‐ranging, mammal species in increasingly human‐dominated landscapes, and that modeling needs to be done at the spatial scales at which conservation decisions are made.     

Remotely sensed forest understory density and nest predator occurrence interact to predict suitable breeding habitat and the occurrence of a resident boreal bird species

Habitat suitability models (HSM) based on remotely sensed data are useful tools in conservation work. However, they typically use species occurrence data rather than robust demographic variables, and their predictive power is rarely evaluated. These shortcomings can result in misleading guidance for conservation. Here, we develop and evaluate a HSM based on correlates of long‐term breeding success of an open nest building boreal forest bird, the Siberian jay. In our study site in northern Sweden, nest failure of this permanent resident species is driven mainly by visually hunting corvids that are associated with human settlements. Parents rely on understory nesting cover as protection against these predators. Accordingly, our HSM includes a light detection and ranging (LiDAR) based metric of understory density around the nest and the distance of the nest to the closest human settlement to predict breeding success. It reveals that a high understory density 15–80 m around nests is associated with increased breeding success in territories close to settlements (<1.5 km). Farther away from human settlements breeding success is highest at nest sites with a more open understory providing a favorable warmer microclimate. We validated this HSM by comparing the predicted breeding success with landscape‐wide census data on Siberian jay occurrence. The correlation between breeding success and occurrence was strong up to 40 km around the study site. However, the HSM appears to overestimate breeding success in regions with a milder climate and therefore higher corvid numbers. Our findings suggest that maintaining patches of small diameter trees may provide a cost‐effective way to restore the breeding habitat for Siberian jays up to 1.5 km from human settlements. This distance is expected to increase in the warmer, southern, and coastal range of the Siberian jay where the presence of other corvids is to a lesser extent restricted to settlements.     

When parks work: Effect of anthropogenic disturbance on occupancy of tropical forest mammals

Protected areas (PAs) in the tropics are vulnerable to human encroachment, and, despite formal protection, they do not fully mitigate anthropogenic threats to habitats and biodiversity. However, attempts to quantify the effectiveness of PAs and to understand the status and changes of wildlife populations in relation to protection efficiency remain limited. Here, we used camera‐trapping data collected over 8 consecutive years (2009–2016) to investigate the yearly occurrences of medium‐to‐large mammals within the Udzungwa Mountains National Park (Tanzania), an area of outstanding importance for biological endemism and conservation. Specifically, we evaluated the effects of habitat and proxies of human disturbance, namely illegal hunting with snares and firewood collection (a practice that was banned in 2011 in the park), on species' occurrence probabilities. Our results showed variability in species' responses to disturbance: The only species that showed a negative effect of the number of snares found on occurrence probability was the Harvey's duiker, a relatively widespread forest antelope. Similarly, we found a moderate positive effect of the firewood collection ban on only the suni, another common antelope, and a negative effect on a large opportunistic rodent, the giant‐pouched rat. Importantly, we found evidence of temporal stability in occurrence probability for all species over the 8‐year study period. Our findings suggest that well‐managed PAs can sustain mammal populations in tropical forests. However, variability among species in their responses to anthropogenic disturbance necessitates consideration in the design of conservation action plans for multiple taxa.     

Status and distribution of anthropogenic pressure in the buffer zone of Nanda Devi Biosphere Reserve in western Himalaya, India

Nanda Devi Biosphere Reserve (NDBR) (2236.74 km²), extending over three civil districts viz, Chamoli, Pithoragarh and Almora of the state of Uttar Pradesh, is an important protected area of the western Himalaya owing to its rich biological and cultural diversity. The human (n = 1856) and livestock population (n = 7785) of 19 settlements in the buffer zone as well as seasonal grazing by 15 000–20 000 migratory sheep and goats were the major sources of anthropogenic pressure in the reserve. The intensity of wood-cutting and lopping of a total of 35 sampled woody species was assessed in the buffer zone as parameters of anthropogenic pressure. Anthropogenic pressure showed restricted distribution due to the sparse location of human settlements and seasonal use of biomass resources by majority of the inhabitants, who live a trans-humane lifestyle. Intensive wood-cutting was limited to within 2 km radius of human settlements while tree lopping was mainly done by the migratory shepherds around timber-line (3600–3800 m). Of the total cut trees, the proportion of 20–60 cm girth class cut trees was recorded more. The regeneration percentage of tree species was higher in Chamoli and Pithoragarh sectors as compared to the Almora sector of the buffer zone. Fuelwood plantation in the degraded lands around villages through peoples participation, introduction of alternate fuel devices and employment opportunities have been suggested to minimize the dependence of local people on biomass resources and ensure the biodiversity conservation in the NDBR.     

Phylogenetic diversity and the conservation biogeography of African primates

Aim Phylogenetics has an important role in conservation biogeography. However, there are few data on the phylogenetic diversity of African primates. The phylogenetic diversity (PD) of a species is a measure of its taxonomic distinctness and can be estimated by looking at the phylogenetic relationships among taxa. Species‐specific metrics on PD can then be used to determine conservation priorities at various biogeographical scales. We used PD metrics to rank 55 African primate species according to their conservation priorities at the country level and within six African biogeographical regions. We also addressed the following question: are there differences in conservation rankings between the IUCN Red List and our PD metrics? Location Africa. Methods We created a consensus phylogeny for all African primate clades based on genetic studies. Analyses of species distributions were determined using presence/absence scores at two levels: country and biogeographical region. A node‐based method that standardizes for widespread taxa and endemicity was used to calculate PD indices. Hierarchical cluster analysis was used to convert one of the standardized, phylogenetic indices into three clusters that could be ranked and compared with the main IUCN conservation rankings of endangered, vulnerable, and lower risk. Results At the country and region levels, the top‐priority species in terms of PD are Pan paniscus, Macaca sylvanus, Arctocebus calabarensis, Gorilla beringei, Arctocebus aureus, Allenopithecus nigroviridis, Gorilla gorilla, Procolobus verus, Cercopithecus solatus, Cercocebus galeritus, Colobus angolensis, Theropithecus gelada, Galagoides zanzibaricus, Galagoides granti, and Procolobus (Piliocolobus) badius. Geographic rankings were highest for the Democratic Republic of the Congo (country level) and Central Africa (region level). Although there were no overall differences between IUCN conservation ranks and the PD rankings, there were significant differences between the two systems for vulnerable and endangered primate taxa. Main conclusions There are few ecological and behavioural data on populations of some of the African primates that represent the highest levels of phylogenetic diversity. Studies of primate taxa with high PD rankings should focus on identifying sites suitable for intensive studies of population densities, feeding ecology, and reproductive behaviour. We suggest that PD metrics can serve as an important, complementary data set in the IUCN ranking system for primates.     

Deactivation of snares by wild chimpanzees

Snare injuries to chimpanzees (Pan troglodytes) have been reported at many study sites across Africa, and in some cases cause the death of the ensnared animal. However, very few snare injuries have been reported concerning the chimpanzees of Bossou, Guinea. The rarity of snare injuries in this study group warrants further consideration, given the exceptionally close proximity of the Bossou chimpanzees to human settlements and the widespread practice of snare hunting in the area. Herein we report a total of six observations of chimpanzees attempting to break and deactivate snares, successfully doing so on two of these occasions. We observed the behavior in 5 males, ranging in age from juveniles to adults. We argue that such active responses to snares must be contributing to the rarity of injuries in this group. Based on our observations, we suggest that the behavior has transmitted down the group. Our research team at Bossou continues to remove snares from the forest, but the threat of ensnarement still remains. We discuss potential ways to achieve a good balance between human subsistence activities and the conservation of chimpanzees at Bossou, which will increasingly be an area of great concern in the future.     

Survival and Cause-Specific Mortality of Corsac and Red Foxes in Mongolia

ABSTRACT The corsac fox (Vulpes corsac) and red fox (Vulpes vulpes) range widely across northern and central Asia and may be declining in many regions due to overhunting and other causes. However, details of the fundamental causes of survival and mortality of both species remain largely unquantified, but may be crucial for understanding interspecific relationships and developing effective conservation actions. We studied a radiomarked population of sympatric corsac and red foxes in central Mongolia to quantify survival and cause-specific mortality rates from April 2005 to April 2007. Survival probability was 0.34 for corsacs (n = 18) and 0.46 for red foxes (n = 17) and did not vary by year within or between each species. Among both foxes, mortality occurred mainly from hunting by humans, but also from predation by larger canids and unknown causes. Our results suggest that illegal human hunting represents the principal source of mortality for both species and that a recently initiated ranger patrol program in the study area did not affect fox survival. As such, more stringent protective measures will likely be necessary to halt declines of both foxes. Our results also suggest that interference competition occurs between species as red foxes killed but did not consume corsacs. Our results will be useful for developing science-based management strategies to protect foxes in Mongolia, and in understanding the competitive relationships between them.     

Legal subsistence hunting trends in the Ugalla ecosystem of western Tanzania

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.     

Interactive effects of road salt and sediment disturbance on the productivity of seven common aquatic macrophytes

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Water quality and phytoplankton community structure in mangrove streams under different logging regimes in Cameroon

Mangrove logging is rampant, and its effects on phytoplankton dynamics have not been investigated. Phytoplankton are valuable in biomonitoring pollution in mangrove ecosystems. This study assessed the relationship between physico‐chemical characteristics of the water and observed phytoplankton community structure, in relation to anthropogenic activities. Water samples were collected from seven sites within the mangrove ecosystem that differed in wood harvesting age and proximity to human settlements. Characterization of samples followed standard methods. pH of all water samples indicated acidity. Phytoplankton species richness and soluble P were positively correlated (r = 0.822, P ≤ 0.023), but no correlations existed with logging age (r = ?0.273, P = 0553). The site with highest soluble phosphorus concentration (Site 4) had highest phytoplankton abundance, diversity and richness. A total of 127 species were identified in 58 families. Euglenaceae was the most abundant family (13 species) and Anacystis sp. the most frequent species (100%). The most common genera were Microcystis and Anacystis, bioindicators of pollution. The site at which harvesting was most recently performed had more eutrophic species, while site harvested earliest (Site 5) had the least. These results are discussed with respect to how anthropogenic activities influence water quality, phytoplankton community structure, mangrove conservation and management.     

Distribution and Conservation Status of the Red-Shanked Douc (Pygathrix nemaeus) in Lao PDR: An Update

The endangered red‐shanked douc (Pygathrix nemaeus), endemic to Lao PDR, Vietnam, and perhaps Cambodia, remains little known. The Lao population is highly threatened. To improve conservation prospects of the species there, we here update a status review from 1999. Subsequent literature (mostly not readily available to the outside scientific community) was reviewed critically. Doucs and their habitat in Lao PDR faced continuous, increasing threats in the past 10 years through large development projects and heavy hunting. Many locations with records from the 1990s were not surveyed in the last decade, so douc persistence remains uncertain in them. Given the poor status of the species in Vietnam and Cambodia, the Lao population is surely the world's largest and the best hope for the species’ global conservation. Resources for conserving species are very limited in the country, urging prioritization of populations, so available resources have maximum effect. Nakai–Nam Theun and Hin Namno National Protected Areas hold the largest populations of P. nemaeus, but face great threats from hunting. Management of these areas (and secondary priority areas) should focus on control of this illegal activity. Am. J. Primatol. 74:874‐889, 2012. © 2012 Wiley Periodicals, Inc.