Encounter data in resource management and ecology: pitfalls and possibilities

Community livelihoods and forest dependency: Tourism contribution in Nyungwe National Park, Rwanda

Introduction

Communities living adjacent to protected areas in Africa are characterized by high poverty rates and their well-being often depends on park resources. This often results in forest degradation and decline in wildlife populations, for example due to illegal hunting for bush meat. To counter this challenge in Rwanda, a tourism revenue sharing program was initiated in 2005, with 5% (doubled to 10% in 2017) of the park gate fees invested in community development projects. We evaluated the effectiveness of this tourism revenue sharing from 2005 to 2017, targeting communities adjacent to Nyungwe National Park located in south-western Rwanda.

Methods

We used questionnaires addressed to members of community associations and local government in 24 sectors around Nyungwe National Park. Additionally, data on illegal resource use and socio-economic status of the surrounding communities were obtained to quantitatively triangulate and draw insights from communities’perceptions. Using spatial analyses and spatial regression, we mapped trends in illegal activities relative to socio-economic characteristics.

Results and discussion

Both the qualitative and quantitative results indicate that the tourism revenue sharing program has not fully succeeded in improving community well-being around Nyungwe National Park. The tourism revenue sharing can consider targeting areas that demonstrate more need and reassessing prioritization of interventions supported by the program to achieve both poverty reduction around Nyungwe National Park and improved conservation outcomes in this protected area.

Detecting wildlife poaching: a rigorous method for comparing patrol strategies using an experimental design

Many studies of wildlife poaching acknowledge the challenges of detecting poaching activities, but few address the issue. Data on poaching may be an inaccurate reflection of the true spatial distribution of events because of low detection rates. The deployment of conservation and law enforcement resources based on biased data could be ineffective or lead to unintended outcomes. Here, we present a rigorous method for estimating the probabilities of detecting poaching and for evaluating different patrol strategies. We illustrate the method with a case study in which imitation snares were set in a private nature reserve in South Africa. By using an experimental design with a known spatial distribution of imitation snares, we estimated the detection probability of the current patrol strategy used in the reserve and compared it to three alternative patrol strategies: spatially focused patrols, patrols with independent observers, and systematic search patterns. Although detection probabilities were generally low, the highest proportion of imitation snares was detected with systematic search strategies. Our study provides baseline data on the probability of detecting snares used for poaching, and presents a method that can be modified for use in other regions and for other types of wildlife poaching.

Understanding spatial patterns of poaching pressure using ranger logbook data to optimize future patrolling strategies

Poaching is driving many species toward extinction, and as a result, lowering poaching pressure is a conservation priority. This requires understanding where poaching pressure is high and which factors determine these spatial patterns. However, the cryptic and illegal nature of poaching makes this difficult. Ranger patrol data, typically recorded in protected area logbooks, contain information on patrolling efforts and poaching detection and should thus provide opportunities for a better understanding of poaching pressure. However, these data are seldom analyzed and rarely used to inform adaptive management strategies. We developed a novel approach to making use of analog logbook records to map poaching pressure and to test environmental criminology and predator-prey relationship hypotheses explaining poaching patterns. We showcase this approach for Golestan National Park in Iran, where poaching has substantially depleted ungulate populations. We digitized data from >4800 ranger patrols from 2014 to 2016 and used an occupancy modeling framework to relate poaching to (1) accessibility, (2) law enforcement, and (3) prey availability factors. Based on predicted poaching pressure and patrolling intensity, we provide suggestions for future patrol allocation strategies. Our results revealed a low probability (12%) of poacher detection during patrols. Poaching distribution was best explained by prey availability, indicating that poachers target areas with high concentrations of ungulates. Poaching pressure was estimated to be high (>0.49) in 39% of our study area. To alleviate poaching pressure, we recommend ramping up patrolling intensity in 12% of the national park, which could be achievable by reducing excess patrols in about 20% of the park. However, our results suggest that for 27% of the park, it is necessary to improve patrolling quality to increase detection probability of poaching, for example, by closing temporal patrolling gaps or expanding informant networks. Our approach illustrates that analog ranger logbooks are an untapped resource for evidence-based and adaptive planning of protected area management. Using this wealth of data can open up new avenues to better understand poaching and its determinants, to expand effectiveness assessments to the past, and, more generally, to allow for strategic conservation planning in protected areas.

Individual and community-level impacts of the unarmed all-women Black Mamba Anti-Poaching Unit

In a conservation setting where escalating tension has been the norm, the unarmed primarily female-composed Black Mambas Anti-Poaching Unit (BMAPU) in South Africa are a successful counterpoint in that they have decimated poaching using only diplomacy and patrols. We sought to understand if the BMAPU is achieving its secondary goal of influencing support for conservation and wildlife among the nearby populace via community-based conservation actions including outreach and environmental education. We also determined the impact that the program has on the Mambas themselves. Using a mixed-methods survey we conducted structured in-person interviews with 120 community members from four communities where the women of the BMAPU live, and among all the women that were on active duty in the BMAPU at the time of the surveys. We found that all participants in the BMAPU program reported improved self and community perception of their societal role as financial providers, as well as their sense of agency and self-efficacy, relative to before becoming rangers. We also found that having BMAPU rangers living in the communities by itself did not contribute to community-level support for wildlife conservation or protected areas. However, one community with both a large-scale children's conservation education program and an equitable distribution of financial benefits paid by the nearby conservation concessionaires was significantly more supportive of wildlife conservation and protected areas than the other three. Further research to parse the relative contributions of the two contributing factors of education and financial benefit would help clarify their relative contributions. From this study, we conclude that a combination of child-focused conservation education programs and equitable distribution of financial benefits leads to increased community support for wildlife, conservation, and protected natural areas, and decreases support for poaching.

Evaluating the reliability of media reports for gathering information about illegal wildlife trade seizures

Illegal wildlife trade (IWT) is threatening many species across the world. It is important to better understand the scale and characteristics of IWT to inform conservation priorities and actions. However, IWT usually takes place covertly, meaning that the data on species, trade routes and volumes is limited. This means that conservationists often have to rely on publicly available law enforcement reports of seizures as potential indicators of the magnitude and characteristics of IWT. Still, even these data may be difficult to access, leading conservationists to use media reports of seizures instead. This is the case in countries like Nepal, which have limited capacity in data keeping and reporting, and no centralized data management system. Yet reliance on media reports risks introducing further biases, which are rarely acknowledged or discussed. Here we characterize IWT in Nepal by comparing data from three sources of information on IWT between January 2005 and July 2017: seizure reports from three Nepali national daily newspapers, official seizure records for Kathmandu district, and data on additional enforcement efforts against IWT in Nepal. We found a strong positive correlation between the number of official and media-reported seizures over time, but media under-reported seizure numbers, with 78% of seizures going unreported. Seizures of charismatic, protected species were reported more often and seizure reports involving tigers were most likely to be reported (57%). Media reports appeared to be a good indicator of trends and the species being seized but not overall seizure number, with the media largely underestimating total seizure numbers. Therefore, media reports cannot be solely relied upon when it comes to informing conservation decision-making. We recommend that conservationists triangulate different data sources when using seizure data reported in the media to more rigorously characterise IWT.

Protected Area Rangers as Cultural Brokers? Implications for Wildlife Crime Prevention in Viet Nam

The scope, scale, and socio-environmental impacts of wildlife crime pose diverse risks to people, animals, and environments. With direct knowledge of the persistence and dynamics of wildlife crime, protected area rangers can be both an essential source of information on, and front-line authority for, preventing wildlife crime. Beyond patrol and crime scene data collected by rangers, solutions to wildlife crime could be better built off the knowledge and situational awareness of rangers, in particular rangers' relationships with local communities and their unique ability to engage them. Rangers are often embedded in the communities surrounding the conserved areas which they are charged with protecting, which presents both challenges and opportunities for their work on wildlife crime prevention. Cultural brokerage refers to the process by which intermediaries, like rangers, facilitate interactions between other relevant stakeholders that are separate yet proximate to one another, or that lack access to, or trust in, one another. Cultural brokers can function as gatekeepers, representatives, liaisons, coordinators, or iterant brokers; these forms vary by how information flows and how closely aligned the broker is to particular stakeholders. The objectives of this paper are to use the example of protected area rangers in Viet Nam to (a) characterize rangers' cultural brokerage of resources, information, and relationships and (b) discuss ranger-identified obstacles to the prevention of wildlife crime as an example of brokered knowledge. Using in-depth face-to-face interviews with rangers and other protected area staff (N = 31, 71% rangers) in Pu Mat National Park, 2018, we found that rangers regularly shift between forms of cultural brokerage. We offer a typology of the diverse forms of cultural brokerage that characterize rangers' relationships with communities and other stakeholders. We then discuss ranger-identified obstacles to wildlife protection as an example of brokered knowledge. These results have implications for designing interventions to address wildlife crime that both improve community-ranger interactions and increase the efficiency of wildlife crime prevention.

Estimating hunting prevalence and reliance on wild meat in Cambodia's Eastern Plains

Hunting is a primary driver of biodiversity loss across South-east Asia. Within Cambodia, the use of wire snares to capture wildlife is a severe threat in protected areas but there have been few studies of the behaviour of hunters from local communities. Here, we combine the unmatched count technique with direct questioning to estimate the prevalence of hunting behaviours and wildlife consumption amongst 705 households living within Keo Seima Wildlife Sanctuary, Cambodia. We assessed respondents’ knowledge of rules, and their perceptions of patrols responsible for enforcing rules. Estimates of hunting behaviour were variable: results from the unmatched count technique were inconclusive, and direct questioning revealed 9% of households hunted, and 20% set snares around farms to prevent wildlife eating crops. Hunting with domestic dogs was the method most commonly used to catch wildlife (87% of households owned dogs). Wild meat was consumed by 84% of households, and was most frequently bought or caught, but also gifted. We detected a high awareness of conservation rules, but low awareness of punishments and penalties, with wildlife depletion, rather than the risk of being caught by patrols, causing the greatest reduction in hunting. Our findings demonstrate the challenges associated with reliably estimating rule-breaking behaviour and highlight the need to incorporate careful triangulation into study design.

Effects of integrated conservation–development projects on unauthorized resource use in Volcanoes National Park, Rwanda: a mixed-methods spatio-temporal approach

This study supplements spatial panel econometrics techniques with qualitative GIS to analyse spatio-temporal changes in the distribution of integrated conservation–development projects relative to poaching activity and unauthorized resource use in Volcanoes National Park, Rwanda. Cluster and spatial regression analyses were performed on data from ranger monitoring containing > 35,000 combined observations of illegal activities in Volcanoes National Park, against tourism revenue sharing and conservation NGO funding data for 2006–2015. Results were enriched with qualitative GIS analysis from key informant interviews. We found a statistically significant negative linear effect of overall integrated conservation–development investments on unauthorized resource use in Volcanoes National Park. However, individually, funding from Rwanda's tourism revenue sharing policy did not have an effect in contrast to the significant negative effect of conservation NGO funding. In another contrast between NGO funding and tourism revenue sharing funding, spatial analysis revealed significant gaps in revenue sharing funding relative to the hotspots of illegal activities, but these gaps were not present for NGO funding. Insight from qualitative GIS analysis suggests that incongruity in prioritization by decision makers at least partly explains the differences between the effects of revenue sharing and conservation NGO investment. Although the overall results are encouraging for integrated conservation–development projects, we recommend increased spatial alignment of project funding with clusters of illegal activities, which can make investment decision-making more data-driven and projects more effective for conservation.

Integrating models of human behaviour between the individual and population levels to inform conservation interventions

Conservation takes place within social-ecological systems, and many conservation interventions aim to influence human behaviour in order to push these systems towards sustainability. Predictive models of human behaviour are potentially powerful tools to support these interventions. This is particularly true if the models can link the attributes and behaviour of individuals with the dynamics of the social and environmental systems within which they operate. Here we explore this potential by showing how combining two modelling approaches (social network analysis, SNA, and agent-based modelling, ABM) could lead to more robust insights into a particular type of conservation intervention. We use our simple model, which simulates knowledge of ranger patrols through a hunting community and is based on empirical data from a Cambodian protected area, to highlight the complex, context-dependent nature of outcomes of information-sharing interventions, depending both on the configuration of the network and the attributes of the agents. We conclude by reflecting that both SNA and ABM, and many other modelling tools, are still too compartmentalized in application, either in ecology or social science, despite the strong methodological and conceptual parallels between their uses in different disciplines. Even a greater sharing of methods between disciplines is insufficient, however; given the impact of conservation on both the social and ecological aspects of systems (and vice versa), a fully integrated approach is needed, combining both the modelling approaches and the disciplinary insights of ecology and social science. This article is part of the theme issue 'Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation'.

Detecting deterrence from patrol data

The threat posed to protected areas by the illegal killing of wildlife is countered principally by ranger patrols that aim to detect and deter potential offenders. Deterring poaching is a fundamental conservation objective, but its achievement is difficult to identify, especially when the prime source of information comes in the form of the patrols' own records, which inevitably contain biases. The most common metric of deterrence is a plot of illegal activities detected per unit of patrol effort (CPUE) against patrol effort (CPUE-E). We devised a simple, mechanistic model of law breaking and law enforcement in which we simulated deterrence alongside exogenous changes in the frequency of offences under different temporal patterns of enforcement effort. The CPUE-E plots were not reliable indicators of deterrence. However, plots of change in CPUE over change in effort (ΔCPUE-ΔE) reliably identified deterrence, regardless of the temporal distribution of effort or any exogenous change in illegal activity levels as long as the time lag between patrol effort and subsequent behavioral change among offenders was approximately known. The ΔCPUE-ΔE plots offered a robust, simple metric for monitoring patrol effectiveness; were no more conceptually complicated than the basic CPUE-E plots; and required no specialist knowledge or software to produce. Our findings demonstrate the need to account for temporal autocorrelation in patrol data and to consider appropriate (and poaching-activity-specific) intervals for aggregation. They also reveal important gaps in understanding of deterrence in this context, especially the mechanisms by which it occurs. In practical applications, we recommend the use of ΔCPUE-ΔE plots in preference to other basic metrics and advise that deterrence should be suspected only if there is a clear negative slope. Distinct types of illegal activity should not be grouped together for analysis, especially if the signs of their occurrence have different persistence times in the environment.

Modelling the rate of successful search of red foxes during population control

Context Relative abundance indices of wildlife can be scaled to give estimates of absolute abundance. Choice of scaling parameter depends on the data available and assumptions made about the relationship between the index and absolute abundance. Predation-mechanics theory suggests that a parameterisation involving the rate of successful search, s, will be useful where the area searched is unknown. An example arises during fox culling on shooting estates in Britain, where detection and cull data from gamekeepers using a spotlight and rifle are available, and can potentially be used to understand the population dynamics of the local population. Aims We aimed to develop an informative prior for s for use within a Bayesian framework to fit a fox population-dynamics model to detection data. Methods We developed a mechanistic model with a rate of successful search parameter for the gamekeeper–fox system. We established a mechanistic prior for s, using Monte Carlo simulation to combine relevant information on its component factors (detection probability, observer field of view and speed of travel). We obtained empirical estimates of s from a distance-sampling study of fox populations using similar survey methods, and used these as data in a Bayesian model to develop a mechanistic–empirical prior. We then applied this informative prior within a state–space model to estimate fox density from fox-detection rate on four estates. Key results The mechanistic–empirical prior for the rate of successful search was lognormally distributed with a median of 2.01 km2 h–1 (CV = 0.56). Underlying assumptions of the parameterisation were met. Local fox-density estimates obtained using informative priors closely reflected regional density. Conclusions A mechanistic understanding of the search process leading to fox detections by gamekeepers, and the use of Bayesian models, allowed the use of diverse sources of information to develop an informative prior for s that was useful in estimating fox density from detection data. Implications Careful use of prior knowledge within a Bayesian modelling framework can reduce uncertainty in population estimates derived from index data, and lead to improved management decisions. The mechanistic approach we have used will have parallel applications in many other contexts.

Spatial variation in leopard (Panthera pardus) site use across a gradient of anthropogenic pressure in Tanzania's Ruaha landscape

Understanding large carnivore occurrence patterns in anthropogenic landscapes adjacent to protected areas is central to developing actions for species conservation in an increasingly human-dominated world. Among large carnivores, leopards (Panthera pardus) are the most widely distributed felid. Leopards occupying anthropogenic landscapes frequently come into conflict with humans, which often results in leopard mortality. Leopards' use of anthropogenic landscapes, and their frequent involvement with conflict, make them an insightful species for understanding the determinants of carnivore occurrence across human-dominated habitats. We evaluated the spatial variation in leopard site use across a multiple-use landscape in Tanzania's Ruaha landscape. Our study region encompassed i) Ruaha National Park, where human activities were restricted and sport hunting was prohibited; ii) the Pawaga-Idodi Wildlife Management Area, where wildlife sport hunting, wildlife poaching, and illegal pastoralism all occurred at relatively low levels; and iii) surrounding village lands where carnivores and other wildlife were frequently exposed to human-carnivore conflict related-killings and agricultural habitat conversion and development. We investigated leopard occurrence across the study region via an extensive camera trapping network. We estimated site use as a function of environmental (i.e. habitat and anthropogenic) variables using occupancy models within a Bayesian framework. We observed a steady decline in leopard site use with downgrading protected area status from the national park to the Wildlife Management Area and village lands. Our findings suggest that human-related activities such as increased livestock presence and proximity to human households exerted stronger influence than prey availability on leopard site use, and were the major limiting factors of leopard distribution across the gradient of human pressure, especially in the village lands outside Ruaha National Park. Overall, our study provides valuable information about the determinants of spatial distribution of leopards in human-dominated landscapes that can help inform conservation strategies in the borderlands adjacent to protected areas.

Who Wants to Save the Forest? Characterizing Community-Led Monitoring in Prey Lang, Cambodia

Community monitoring is believed to be successful only where there is sustained funding, legislation for communities to enforce rules, clear tenure rights, and an enabling environment created by the state. Against this backdrop, we present the case of an autonomous grassroots-monitoring network that took the initiative to protect their forest, in a context, where no external incentives and rule enforcement power were provided. The aim was to analyze the socio-demographic and economic backgrounds, motivations and achievements of forest monitors, compared to non-monitors in the same communities. A total of 137 interviews were conducted in four villages bordering Prey Lang forest in Cambodia. We used binary logit models to identify the factors that influenced the likelihood of being a monitor. Results show that there were few (22%, n = 30) active monitors. Active monitors were intrinsically motivated forest-users, and not specifically associated with a particular gender, ethnicity, or residence-time in that area. The most common interventions were with illegal loggers, and the monitors had a general feeling of success in stopping the illegal activities. Most (73%, n = 22) of them had been threatened by higher authorities and loggers. Our results show that despite the lack of power to enforce rules, absence of external funding and land-ownership rights, and enduring threats of violence and conflicts, autonomous community monitoring may take place when community members are sufficiently motivated by the risk of losing their resources.

Design, monitoring and evaluation of a direct payments approach for an ecotourism strategy to reduce illegal hunting and trade of wildlife in Lao PDR

Ecotourism as a strategy for achieving biodiversity conservation often results in limited conservation impact relative to its investment and revenue return. In cases where an ecotourism strategy has been used, projects are frequently criticized for not providing sufficient evidence on how the strategy has reduced threats or improved the status of the biodiversity it purports to protect. In Lao PDR, revenue from ecotourism has not been directly linked to or dependent on improvements in biodiversity and there is no evidence that ecotourism enterprises have contributed to conservation. In other developing countries, direct payments through explicit contracts in return for ecosystem services have been proposed as a more cost-effective means for achieving conservation, although further research is needed to evaluate the impact of this approach. To address this need, a new model was tested in the Nam Et-Phou Louey National Protected Area (NPA) in Lao PDR using a direct payments approach to create ecotourism incentives for villagers to increase wildlife populations. Over a four-year period, we monitored along a theory of change to evaluate assumptions about the linkages between intermediate results and biological outcomes. Preliminary results show a negative correlation between ecotourism benefits and hunting infractions in target villages; no increase in hunting sign in the ecotourism sector of the NPA relative to a three-fold increase in hunting sign across the NPA’s non-tourism sectors; and an overall increase in wildlife sightings. This case provides key lessons on the design of a direct payments approach for an ecotourism strategy, including how to combine threat monitoring and data on wildlife sightings to evaluate strategy effectiveness, on setting rates for wildlife sightings and village fees, and the utility of the approach for protecting very rare species.

Indicators of success for smart law enforcement in protected areas: A case study for Russian Amur tiger (Panthera tigris altaica) reserves

Although considerable conservation resources have been committed to develop and use law enforcement monitoring and management tools such as SMART, measures of success are ill-defined and, to date, few reports detail results post-implementation. Here, we present 4 case studies from protected areas with Amur tigers (Panthera tigris altaica) in Russia, in which indicators of success were defined and evaluated at each. The ultimate goal was an increase in tiger numbers to 1 individual/100 km(2) at each site. We predicted that improvements in law enforcement effectiveness would be followed by increases in prey numbers and, subsequently, tiger numbers. We used short-term and long-term indicators of success, including: (i) patrol team effort and effectiveness; (ii) catch per unit effort indicators (to measure reductions in threats); and (iii) changes in target species numbers. In addition to implementing a monitoring system, we focused on improving law enforcement management using an adaptive management process. Over 4 years, we noted clear increases in patrol effort and a partial reduction in threats. Although we did not detect clear trends in ungulate numbers, tiger populations remained stable or increased, suggesting that poaching of tigers may be more limiting than prey depletion. Increased effectiveness is needed before a clear reduction in threats can be noted, and more time is needed before detecting responses in target populations. Nonetheless, delineation of concrete goals and indicators of success provide a means of evaluating progress and weaknesses. Such monitoring should be a central component of law enforcement strategies for protected areas.

Effects of anthropogenic mortality on Critically Endangered red wolf Canis rufus breeding pairs: implications for red wolf recovery

Following precipitous population declines as a result of intensive hunting and 20th century predator-control programmes, hybridization of the Critically Endangered red wolf Canis rufus with coyotes Canis latrans posed a significant challenge for red wolf recovery efforts. Anthropogenic mortality and hybridization continue to pose challenges; the increasing number of wolf deaths caused by humans has limited wolf population growth, facilitated the encroachment of coyotes into eastern North Carolina, and affected the formation and disbandment of breeding pairs. We assessed the effects of anthropogenic mortality on Canis breeding units during a 22-year period (1991–2013). Our results show that deaths caused by people accounted for 40.6% of breeding pair disbandment, and gunshots were the primary cause of mortality. Red wolves replaced congeneric breeding pairs > 75% of the time when pairs disbanded under natural conditions or as a result of management actions. Since the mid 2000s anthropogenic mortality has caused annual preservation rates of red wolf breeding pairs to decline by 34%, and replacement of Canis breeders by red wolves to decline by 30%. Our results demonstrate that human-caused mortality, specifically by gunshots, had a strong negative effect on the longevity of red wolf pairs, which may benefit coyotes indirectly by removing their primary competitor. Coyotes are exacerbating the decline of red wolves by pair-bonding with resident wolves whose mates have been killed.

Spatiotemporal trends of illegal activities from ranger-collected data in a Ugandan national park

Within protected areas, biodiversity loss is often a consequence of illegal resource use. Understanding the patterns and extent of illegal activities is therefore essential for effective law enforcement and prevention of biodiversity declines. We used extensive data, commonly collected by ranger patrols in many protected areas, and Bayesian hierarchical models to identify drivers, trends, and distribution of multiple illegal activities within the Queen Elizabeth Conservation Area (QECA), Uganda. Encroachment (e.g., by pastoralists with cattle) and poaching of noncommercial animals (e.g., snaring bushmeat) were the most prevalent illegal activities within the QECA. Illegal activities occurred in different areas of the QECA. Poaching of noncommercial animals was most widely distributed within the national park. Overall, ecological covariates, although significant, were not useful predictors for occurrence of illegal activities. Instead, the location of illegal activities in previous years was more important. There were significant increases in encroachment and noncommercial plant harvesting (nontimber products) during the study period (1999-2012). We also found significant spatiotemporal variation in the occurrence of all activities. Our results show the need to explicitly model ranger patrol effort to reduce biases from existing uncorrected or capture per unit effort analyses. Prioritization of ranger patrol strategies is needed to target illegal activities; these strategies are determined by protected area managers, and therefore changes at a site-level can be implemented quickly. These strategies should also be informed by the location of past occurrences of illegal activity: the most useful predictor of future events. However, because spatial and temporal changes in illegal activities occurred, regular patrols throughout the protected area, even in areas of low occurrence, are also required.

Primates decline rapidly in unprotected forests: evidence from a monitoring program with data constraints

Growing threats to primates in tropical forests make robust and long-term population abundance assessments increasingly important for conservation. Concomitantly, monitoring becomes particularly relevant in countries with primate habitat. Yet monitoring schemes in these countries often suffer from logistic constraints and/or poor rigor in data collection, and a lack of consideration of sources of bias in analysis. To address the need for feasible monitoring schemes and flexible analytical tools for robust trend estimates, we analyzed data collected by local technicians on abundance of three species of arboreal monkey in the Udzungwa Mountains of Tanzania (two Colobus species and one Cercopithecus), an area of international importance for primate endemism and conservation. We counted primate social groups along eight line transects in two forest blocks in the area, one protected and one unprotected, over a span of 11 years. We applied a recently proposed open metapopulation model to estimate abundance trends while controlling for confounding effects of observer, site, and season. Primate populations were stable in the protected forest, while the colobines, including the endemic Udzungwa red colobus, declined severely in the unprotected forest. Targeted hunting pressure at this second site is the most plausible explanation for the trend observed. The unexplained variability in detection probability among transects was greater than the variability due to observers, indicating consistency in data collection among observers. There were no significant differences in both primate abundance and detectability between wet and dry seasons, supporting the choice of sampling during the dry season only based on minimizing practical constraints. Results show that simple monitoring routines implemented by trained local technicians can effectively detect changes in primate populations in tropical countries. The hierarchical Bayesian model formulation adopted provides a flexible tool to determine temporal trends with full account for any imbalance in the data set and for imperfect detection.

Breaking the vicious circle of illegal logging in Indonesia

The government of Indonesia, which presides over 10% of the world's tropical forests, has set ambitious targets to cut its high deforestation rates through an REDD+ scheme (Reducing Emissions from Deforestation and forest Degradation). This will require strong law enforcement to succeed. Yet, strategies that have accomplished this are rare and, along with past failures, tend not to be documented. We evaluated a multistakeholder approach that seeks to tackle illegal logging in the carbon-rich province of Aceh, Sumatra. From 2008 to 2009, Fauna & Flora International established and supported a community-based informant network for the 738,000 ha Ulu Masen ecosystem. The network reported 190 forest offenses to local law enforcement agencies, which responded with 86 field operations that confiscated illicit vehicles, equipment, and timber, and arrested 138 illegal logging suspects. From 45 cases subsequently monitored, 64.4% proceeded to court, from which 90.0% of defendants received a prison sentence or a verbal warning for a first offense. Spatial analyses of illegal logging and timber storage incidents predicted that illegal activities would be more effectively deterred by law enforcement operations that targeted the storage sites. Although numerous clusters of incidents were identified, they were still widespread reflecting the ubiquity of illegal activities. The multistakeholder results were promising, but illegal logging still persisted at apparently similar levels at the project's end, indicating that efforts need to be further strengthened. Nevertheless, several actions contributed to the law enforcement achievements: strong political will; strong stakeholder support; and funding that could be promptly accessed. These factors are highlighted as prerequisites for achieving Indonesia's ambitious REDD+ goals.

Hunting, law enforcement, and African primate conservation

Primates are regularly hunted for bushmeat in tropical forests, and systematic ecological monitoring can help determine the effect hunting has on these and other hunted species. Monitoring can also be used to inform law enforcement and managers of where hunting is concentrated. We evaluated the effects of law enforcement informed by monitoring data on density and spatial distribution of 8 monkey species in Taï National Park, Côte d'Ivoire. We conducted intensive surveys of monkeys and looked for signs of human activity throughout the park. We also gathered information on the activities of law-enforcement personnel related to hunting and evaluated the relative effects of hunting, forest cover and proximity to rivers, and conservation effort on primate distribution and density. The effects of hunting on monkeys varied among species. Red colobus monkeys (Procolobus badius) were most affected and Campbell's monkeys (Cercopithecus campbelli) were least affected by hunting. Density of monkeys irrespective of species was up to 100 times higher near a research station and tourism site in the southwestern section of the park, where there is little hunting, than in the southeastern part of the park. The results of our monitoring guided law-enforcement patrols toward zones with the most hunting activity. Such systematic coordination of ecological monitoring and law enforcement may be applicable at other sites.

Hierarchical multi-species modeling of carnivore responses to hunting, habitat and prey in a West African protected area

Protected areas (PAs) are a cornerstone of global efforts to shield wildlife from anthropogenic impacts, yet their effectiveness at protecting wide-ranging species prone to human conflict--notably mammalian carnivores--is increasingly in question. An understanding of carnivore responses to human-induced and natural changes in and around PAs is critical not only to the conservation of threatened carnivore populations, but also to the effective protection of ecosystems in which they play key functional roles. However, an important challenge to assessing carnivore communities is the often infrequent and imperfect nature of survey detections. We applied a novel hierarchical multi-species occupancy model that accounted for detectability and spatial autocorrelation to data from 224 camera trap stations (sampled between October 2006 and January 2009) in order to test hypotheses about extrinsic influences on carnivore community dynamics in a West African protected area (Mole National Park, Ghana). We developed spatially explicit indices of illegal hunting activity, law enforcement patrol effort, prey biomass, and habitat productivity across the park, and used a Bayesian model selection framework to identify predictors of site occurrence for individual species and the entire carnivore community. Contrary to our expectation, hunting pressure and edge proximity did not have consistent, negative effects on occurrence across the nine carnivore species detected. Occurrence patterns for most species were positively associated with small prey biomass, and several species had either positive or negative associations with riverine forest (but not with other habitat descriptors). Influences of sampling design on carnivore detectability were also identified and addressed within our modeling framework (e.g., road and observer effects), and the multi-species approach facilitated inference on even the rarest carnivore species in the park. Our study provides insight for the conservation of these regionally significant carnivore populations, and our approach is broadly applicable to the robust assessment of communities of rare and elusive species subject to environmental change.