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Rapid environmental change threatens to isolate the world’s wildlife populations and intensify biodiversity loss. Global policies have called for expanding and connecting the world’s protected areas (PAs) to curtail the crisis, yet how well PA networks currently support wildlife movement, and where connectivity conservation or restoration is most critical, have never been mapped globally. Here, we map the functional connectivity (how animals move through landscapes) of the world’s terrestrial PAs for the first time. Also, going beyond existing global connectivity indices, we quantify national PA-connectedness using an approach that meaningfully represents animal movement through anthropogenic landscapes. We find that reducing the human footprint may improve national PA-connectivity more than adding new PAs; however, both strategies are critical for improving and preserving connectivity in places where the predicted flow of animal movement is highly concentrated. We show that the majority of critical connectivity areas (CCAs) (defined as globally important areas of concentrated animal movements) remain unprotected. Of these, 72% overlap with previously-identified global conservation priority areas, while 3% of CCAs occur within moderate to heavily modified lands. Conservation and restoration of CCAs could safeguard connectivity of the world’s PAs, and dovetail with previously identified global conservation priorities.

Wildlife-based tourism poses opportunities and challenges for species conservation. Minimizing potential negative impacts of tourism is critical to ensure business and conservation enterprises can coexist. In north-western Namibia tourism is used as a conservation tool for the Critically Endangered black rhinoceros Diceros bicornis. However, black rhinoceroses are susceptible to human disturbance and may become displaced by tourist activities, which threatens not only the security and health of the rhinoceros population but also the sustainability of the business. We examined areas avoided by black rhinoceroses to understand how they respond to the type and extent of tourism development, and to evaluate management alternatives. We used spatial data on use of water sources by rhinoceroses to create a series of a priori candidate models that described the negative influences of tourist activities on rhinoceros habitat use. A model selection approach strongly supported a cumulative zones of influence model comprised of a 6 km buffer around the airstrip combined with a 1 km buffer around roads used daily. We compared alternative management scenarios using the best-performing model and found that an optimal road-use policy combined with airstrip relocation could minimize the total area avoided by the black rhinoceros to 7.1% and loss of high quality habitat to 20.7%. Under the worst-case scenario the area avoided and loss of high quality habitat were 153 and 85% greater, respectively, than under the scenario with optimal management. Our findings provide a novel framework and a practical, policy-relevant decision support tool to improve the contribution of tourism to wildlife conservation.

While corridors in conservation have a long history of use, evaluations of proposed or existing corridors in conservation landscapes are important to avoid the same fate as poorly-functioning “paper parks”. We used resistance surface modeling and circuit theory to evaluate a number of corridors developed at regional and at local scales that aim to improve connectivity for large wildlife in the central part of the Kavango-Zambezi transfrontier conservation area. We used hourly GPS data from 16 collared African elephants (Loxodonta africana), and associated environmental data at used versus available movement paths, to develop a hierarchical Bayesian path selection function model. We used the resulting resistance surface across the study area as an input into circuit theory modeling to assess how well connectivity levels were captured by both types of corridors relative to several alternative scenarios. We found that the majority of regional-scale corridors performed relatively well at capturing elevated levels of connectivity relative to non-corridor comparisons, with 7 of 9 corridors rated as good or better in terms of how they captured electrical current levels (a proxy for connectivity). In contrast, only 14 of 33 smaller-scale, local corridors captured significantly higher levels of connectivity than adjacent non-corridor areas. Our results have practical implications for the design and implementation of wildlife connectivity conservation efforts in the world's largest transfrontier conservation landscape. Modern connectivity science approaches can help evaluate which proposed corridors are likely to function as intended, and which may need further refinement.

The functional trait diversity of species assemblages can predict the provision of ecosystem services such as pollination and carbon sequestration, but it is unclear whether the same trait‐based framework can be applied to identify the factors that underpin cultural ecosystem services and disservices. To explore the relationship between traits and the contribution of species to cultural ecosystem services and disservices, we conducted 404 questionnaire surveys with birdwatchers and local residents in Guanacaste, Costa Rica. We used an information–theoretic approach to identify which of 20 functional traits for 199 Costa Rican bird species best predicted their cultural ecosystem service scores related to birdwatching, acoustic aesthetics, education and local identity, as well as disservices (e.g. harm to crops). We found that diet was the most important variable explaining perceptions of cultural ecosystem service and disservice providers. Aesthetic traits such as plumage colour and pattern were important in explaining birdwatching scores. We also found people have a high affinity for forest‐affiliated birds. The insight that functional traits can explain variation among cultural perspectives on values derived from birds offers a first step towards a trait‐based system for understanding the species attributes that underpin cultural ecosystem services and disservices.

Ensuring the persistence of biodiversity and ecosystem services represents a global challenge that need to be addressed with high urgency. Global priority areas can only be identified by means of an integrated prioritization approach that would not only preserve species numbers and ecosystem services, but also the evolutionary and functional components of diversity. In this study we combine global datasets on the distribution of mammals and birds with species traits and phylogenetic data and we identify conservation priorities for taxonomic, functional and phylogenetic diversity, as well as for three ecosystem services, including potential for carbon sequestration, pollination potential and groundwater recharge. We show that, when priority areas are identified based only on individual, e.g. functional diversity, or any combination of the three biodiversity components, these areas do not allow a sufficient protection of the three ecosystem services. However, an integrated approach whereby prioritization is based on all biodiversity components and ecosystem services would allow to identify areas that maximize protection of all ecosystem services with a minimal loss in biodiversity coverage. Our results highlight the need for an integrated conservation planning framework in order to optimally allocate resources and achieve the long-term preservation of the multiple dimensions of biodiversity and ecosystems services.

With increasing energy costs and renewed focus on using energy in ways that support the environment, a structured approach is required to ensure that energy is used efficiently. A comprehensive motor management strategy to reduce motor life cycle costs while increasing reliability is presented. The application of energy management principles is combined with benefits that can be obtained from using energy-efficiency motors. An economic model for determining the optimal time a motor should be replaced with a higher efficiency motor is proposed. The strategy presented incorporates benefits that can be obtained from using in-situ motor efficiency estimation and condition monitoring techniques as part of a motor management system.

An accurate method of estimating the efficiency of in-service motors is needed in order to determine the performance of installed motors without disrupting the motor driven process. In this paper, the motor efficiency is estimated using a non-intrusive implementation of the compensated slip method. The motor speed is accurately estimated using motor vibration signature analysis. A few other efficiency estimation techniques are implemented and their performance is compared to the proposed method. It was found that the non-intrusive compensated slip method produced relatively accurate results without having an adverse impact on the availability of the motor under test. This method provides an attractive alternative to highly intrusive techniques that offer similar accuracy.

We propose the wildlife premium mechanism as an innovation to conserve endangered large vertebrates. The performance-based payment scheme would allow stakeholders in lower-income countries to generate revenue by recovering and maintaining threatened fauna that can also serve as umbrella species (i.e., species whose protection benefits other species with which they co-occur). There are 3 possible options for applying the premium: option 1, embed premiums in a carbon payment; option 2, link premiums to a related carbon payment, but as independent and legally separate transactions; option 3, link premiums to noncarbon payments for conserving ecosystem services (PES). Each option presents advantages, such as incentive payments to improve livelihoods of rural poor who reside in or near areas harboring umbrella species, and challenges, such as the establishment of a subnational carbon credit scheme. In Kenya, Peru, and Nepal pilot premium projects are now underway or being finalized that largely follow option 1. The Kasigau (Kenya) project is the first voluntary carbon credit project to win approval from the 2 leading groups sanctioning such protocols and has already sold carbon credits totaling over $1.2 million since June 2011. A portion of the earnings is divided among community landowners and projects that support community members and has added over 350 jobs to the local economy. All 3 projects involve extensive community management because they occur on lands where locals hold the title or have a long-term lease from the government. The monitoring, reporting, and verification required to make premium payments credible to investors include transparent methods for collecting data on key indices by trained community members and verification of their reporting by a biologist. A wildlife premium readiness fund would enable expansion of pilot programs needed to test options beyond those presented here.

SUMMARYPayments for ecosystem services (PES) programmes are widely recognized as novel and innovative mechanisms that seek to promote the conservation of biodiversity while simultaneously improving human livelihoods. A number of national-level PES programmes have made significant contributions to advancing knowledge of these mechanisms. Namibia's community-based natural resources management (CBNRM) programme effectively operates as one such large-scale PES programme, making it one of the world's longest-standing schemes. In this review, Namibia's CBNRM scheme is compared and contrasted with the formal definition of a PES programme, some of the outcomes that the programme has produced illustrated by examples, and the challenges that must still be faced identified. Most of the requirements for a PES programme are present in Namibia's CBNRM programme, and when it does not meet these criteria, it is not exceptional. Notwithstanding the increases in wildlife populations and financial benefits that have been associated with the programme, a major challenge going forward revolves around diversifying the number of services produced. Namibia's CBNRM programme has much to contribute to the design of large-scale PES schemes.

Summary 1. The conservation of biodiversity is increasingly justified by claims that human livelihoods are improved through its protection. Nature’s ecosystem services do indeed benefit people, but how necessary is a diversity of living things to provide these services? Most studies cited as addressing this question in natural systems do not actually quantify relevant metrics (e.g. species richness) and assess their relationship with services and ⁄ or economic benefits. On the other hand, numerous small-scale experimental studies have demonstrated that more diverse systems do indeed tend to function better, but the relevance of these results to much larger, more complex socio-ecological systems is unclear. 2. Here, we investigate how biodiversity affects the gains from two ecosystem services, trophy hunting and ecotourism, in communal conservancies of Namibia, an arid country in southern Africa. We used statistical methods to explicitly control for confounding variables so that the effect of biodiversity per se on financial benefits to local communities was isolated. 3. Our results show that biodiversity exerts a positive effect on the economic benefits generated from these two ecosystem services produced on communal lands in Namibia. The richness of large wildlife species is positively related to income derived from ecotourism and trophy hunting after statistically controlling for potentially confounding variables such as a conservancy’s geographic characteristics and human population size. 4. Synthesis and applications. Our results demonstrate that the conservation of biodiversity can indeed generate increased services from real-world ecosystems, in this case for the benefit of impoverished rural communities in sub-Saharan Africa. More such studies are needed from various ecological and socioeconomic contexts in order to boost the evidence base for positive effects of biodiversity on ecosystem services.

There exist few quantitative assessments of the relationship between biodiversity per se and economic benefits at scales that are relevant for conservation. Similarly, the merits of Community-Based Natural Resource Management programs for both wildlife and people are contested. Here, we harness two databases, on wildlife surveys and financial benefits, to address these issues for communal conservancies in northwest Namibia. We use ordination methods to characterize the diversity and stability of large wildlife assemblages on conservancies, and demonstrate that diversity (but not stability) is an important explanator of conservancy financial benefits. Our results indicate that for this area of Namibia, biodiversity, as represented by large wildlife assemblages, has an important, positive effect on the tangible financial benefits that people derive from conservation programs.

Marine protected areas (MPAs) are a popular conservation strategy, but their impacts on human welfare are poorly understood. To inform future research and policy decisions, we reviewed the scientific literature to assess MPA impacts on five indicators of human welfare: food security, resource rights, employ- ment, community organization, and income. Following MPA establishment, food security generally remained stable or increased in older and smaller MPAs. The ability of most fishing groups to govern MPA resources changed. Increased resource rights were positively correlated with MPA zoning and compliance with MPA regulations. Small sample sizes precluded statistical tests of the impacts of MPAs on employment, community organization, and income. Our results demonstrate that MPAs shape the social well-being and political power of fishing communities; impacts (positive and negative) vary within and among social groups; and social impacts are correlated with some—but not all—commonly hypothesized explanatory factors. Accordingly, MPAs may represent a viable strategy for enhancing food security and empowering local communities, but current practices negatively affect at least a minority of fishers. To inform policy making, further research must better document and explain variation in the positive and negative social impacts of MPAs.

Designing conservation areas entails costs that, if considered explicitly, can be minimized while still achieving conservation targets. Here we focus on opportunity costs which measure forgone benefits from alternative land uses. Conservation planning studies often use partial estimates of costs, but the extent to which these result in actual efficiencies has not been demonstrated. Our study partitions land costs into three distinct opportunity costs to smallholder agriculture, soybean agriculture and ranching. We demonstrate that opportunity costs to single stakeholder groups can be inaccurate measures of true opportunity costs and can inadvertently shift conservation costs to affect groups of stakeholders disproportionately. Additionally, we examine how spatial correlations between costs as well as target size affect the performance of opportunity costs to single stakeholder groups as surrogate measures of true opportunity costs. We conclude that planning with opportunity costs to single stakeholder groups can result in cost burdens to other groups that could undermine the long-term success of conservation. Thus, an understanding of the spatial distributions of opportunity costs that are disaggregated to groups of stakeholders is necessary to make informed decisions about priority conservation areas.

Nature provides a wide range of benefits to people. There is increasing consensus about the importance of incorporating these “ecosystem services” into resource management decisions, but quantifying the levels and values of these services has proven difficult. We use a spatially explicit modeling tool, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), to predict changes in ecosystem services, biodiversity conservation, and commodity production levels. We apply InVEST to stakeholder-defined scenarios of land-use/land-cover change in the Willamette Basin, Oregon. We found that scenarios that received high scores for a variety of ecosystem services also had high scores for biodiversity, suggesting there is little tradeoff between biodiversity conservation and ecosystem services. Scenarios involving more development had higher commodity production values, but lower levels of biodiversity conservation and ecosystem services. However, including payments for carbon sequestration alleviates this tradeoff. Quantifying ecosystem services in a spatially explicit manner, and analyzing tradeoffs between them, can help to make natural resource decisions more effective, efficient, and defensible.

Research in systematic conservation planning has focused heavily on biological considerations, even though a growing number of studies demonstrate that integrating economic costs into the planning process markedly increases the efficiency of resulting plans. At the global scale, the availability of biodiversity maps is increasing, but analogous maps for economic factors that affect biodiversity conservation are rare, and no study has examined global conservation planning at high resolution using both biodiversity and cost information. Here, we integrate spatial information on crop productivity, livestock density, and prices to produce a global map of the gross economic rents from agricultural lands. We then illustrate the importance of including such opportunity costs in global planning for the conservation of endemic vertebrate species. Plans that consider costs represent endemic species at 10-33% of the opportunity cost of plans that do not, and produce priority sets that diverge from existing schemes. Given scarce resources and the great cost-effectiveness of plans that consider both biodiversity and costs, mapping of the economic costs of conservation should receive similar levels of research attention as mapping of biodiversity. (C) 2007 Elsevier Ltd. All rights reserved.

Community-based natural resource management (CBNRM) is a major global strategy for enhancing conservation outcomes while also seeking to improve rural livelihoods; however, little evidence of socioeconomic outcomes exists. We present a national-level analysis that empirically estimates socioeconomic impacts of CBNRM across Tanzania, while systematically controlling for potential sources of bias. Specifically, we apply a difference-indifferences model to national-scale, cross-sectional data to estimate the impact of three different CBNRM governance regimes on wealth, food security and child health, considering differential impacts of CBNRM on wealthy and poor populations. We also explore whether or not longer-standing CBNRM efforts provide more benefits than recently-established CBNRM areas. Our results show significant improvements in household food security in CBNRM areas compared with non-CBNRM areas, but household wealth and health outcomes in children are generally not significantly different. No one CBNRM governance regime demonstrates consistently different welfare outcomes than the others. Wealthy households benefit more from CBNRM than poor households and CBNRM benefits appear to increase with longer periods of implementation. Perhaps evidence of CBNRM benefits is limited because CBNRM hasn't been around long enough to yield demonstrable outcomes. Nonetheless, achieving demonstrable benefits to rural populations will be crucial for CBNRM's future success in Tanzania.

Biodiversity conservation, as an environmental goal, is increasingly recognized to be connected to the socioeconomic well-being of local communities. The development of a widespread community-based natural resource management (CBNRM) program in Namibia makes it an ideal location to analyze the connection between conservation and socioeconomic well-being of local communities. Namibia's CBNRM program involves the formation of communal conservancies within rural communities and previous studies have found it to be successful on both ecological and economic fronts. In order to broaden the understanding of the program's impact to include social factors, we have conducted a comparative analysis to determine the effects of this program on household welfare outcomes. Data from two rounds of the Namibia Demographic and Health Surveys (2000 and 2006/07) and quasi-experimental statistical methods were used to evaluate changes in various health, education and wealth outcomes of those living in conservancies, relative to non-conservancy comparison groups. Regression results indicate mixed effects of the conservancy program at the household level. The program had positive effects on some health outcome variables, including bednet ownership, which was twice as likely to increase over time in conservancy compared to non-conservancy households. Program impacts were negative for education outcomes, with the proportion of school attendance of conservancy children being 45% less likely to increase over time than non-conservancy children. Wealth outcome results were inconclusive. Our findings highlight the importance of analyzing community conservation programs at a variety of scales when evaluating overall impact, as community-level benefits may not necessarily extend down to the household level (and vice versa).

The benefits of nature-based tourism to biodiversity conservation are often presumed but rarely quantified. The relative value placed on attributes of nature parks is unknown, as is the contribution of biodiversity to tourists' willingness to visit a particular protected area. We surveyed tourists and foreign residents in Uganda to determine how preferences for particular protected areas are formed. We evaluated tourists' demand for elevated biodiversity levels (increased numbers of bird species seen), relative to other protected areas attributes. As the number of bird species increased, tourists demonstrated increased willingness to visit a protected area, independently of all other factors. We used these results to evaluate a revenue-maximizing park management strategy, and consider how revenues from nature-based tourism compare with those from local agricultural land-uses.

Prioritizing land for conservation often competes with other societal objectives, such as housing developments, recreation, agricultural or industrial development, and resource extraction. The number of potentially competing objectives can complicate conservation planning decisions. Although there are potential tradeoffs among conservation for biodiversity, ecosystem services (ecological processes benefiting people), and economic costs, a systemic planning framework can help to identify synergies. By comparing alternative options for prioritizing conservation efforts, tradeoffs among various objectives can be evaluated, including conserving biodiversity, supplying ecosystem services, and minimizing costs. Herein, the recent research that is advancing these frontiers is described.

In light of the significance that ecosystem service research is likely to play in linking conservation activities and human welfare, systematic approaches to measuring, modeling and mapping ecosystem services (and their value to society) are sorely needed. In this paper we outline one such approach, which we developed in order to understand the links between the functioning of the ecosystems of Tanzania’s Eastern Arc Mountains and their impact on human welfare at local, regional and global scales. The essence of our approach is the creation of a series of maps created using field-based or remotely sourced data, data-driven models, and socio-economic scenarios coupled with rule-based assumptions. Here we describe the construction of this spatial information and how it can help to shed light on the complex relationships between ecological and social systems. There are obvious difficulties in operationalizing this approach, but by highlighting those which we have encountered in our own case-study work, we have also been able to suggest some routes to overcoming these impediments.

Global efforts to conserve biodiversity have the potential to deliver economic benefits to people (i.e., “ecosystem services”). However, regions for which conservation benefits both biodiversity and ecosystem services cannot be identified unless ecosystem services can be quantified and valued and their areas of production mapped. Here we review the theory, data, and analyses needed to produce such maps and find that data availability allows us to quantify imperfect global proxies for only four ecosystem services. Using this incomplete set as an illustration, we compare ecosystem service maps with the global distributions of conventional targets for biodiversity conservation. Our preliminary results show that regions selected to maximize biodiversity provide no more ecosystem services than regions chosen randomly. Furthermore, spatial concordance among different services, and between ecosystem services and established conservation priorities, varies widely. Despite this lack of general concordance, “win–win” areas—regions important for both ecosystem services and biodiversity—can be usefully identified, both among ecoregions and at finer scales within them. An ambitious interdisciplinary research effort is needed to move beyond these preliminary and illustrative analyses to fully assess synergies and trade-offs in conserving biodiversity and ecosystem services.

It has become essential in policy and decision-making circles to think about the economic benefits (in addition to moral and scientific motivations) humans derive from wellfunctioning ecosystems. The concept of ecosystem services has been developed to address this link between ecosystems and human welfare. Since policy decisions are often evaluated through cost-benefit assessments, an economic analysis can help make ecosystem service research operational. In this paper we provide some simple economic analyses to discuss key concepts involved in formalizing ecosystem service research. These include the distinction between services and benefits, understanding the importance of marginal ecosystem changes, formalizing the idea of a safe minimum standard for ecosystem service provision, and discussing how to capture the public benefits of ecosystem services. We discuss how the integration of economic concepts and ecosystem services can provide policy and decision makers with a fuller spectrum of information for making conservation-conversion trade-offs. We include the results from a survey of the literature and a questionnaire of researchers regarding how ecosystem service research can be integrated into the policy process. We feel this discussion of economic concepts will be a practical aid for ecosystem service research to become more immediately policy relevant. © 2008 by the Ecological Society of America.

Despite increasing attention to the human dimension of conservation projects, a rigorous, systematic methodology for planning for ecosystem services has not been developed. This is in part because flows of ecosystem services remain poorly characterized at local-to-regional scales, and their protection has not generally been made a priority. We used a spatially explicit conservation planning framework to explore the trade-offs and opportunities for aligning conservation goals for biodiversity with six ecosystem services (carbon storage, flood control, forage production, outdoor recreation, crop pollination, and water provision) in the Central Coast ecoregion of California, United States. We found weak positive and some weak negative associations between the priority areas for biodiversity conservation and the flows of the six ecosystem services across the ecoregion. Excluding the two agriculture-focused services—crop pollination and forage production—eliminates all negative correlations. We compared the degree to which four contrasting conservation network designs protect biodiversity and the flow of the six services. We found that biodiversity conservation protects substantial collateral flows of services. Targeting ecosystem services directly can meet the multiple ecosystem services and biodiversity goals more efficiently but cannot substitute for targeted biodiversity protection (biodiversity losses of 44% relative to targeting biodiversity alone). Strategically targeting only biodiversity plus the four positively associated services offers much promise (relative biodiversity losses of 7%). Here we present an initial analytical framework for integrating biodiversity and ecosystem services in conservation planning and illustrate its application. We found that although there are important potential trade-offs between conservation for biodiversity and for ecosystem services, a systematic planning framework offers scope for identifying valuable synergies., A spatially explicit framework reveals whether areas important for the provision of ecosystem services align with areas important for biodiversity conservation and indicates the need to broaden current conservation goals.

Conservation scientists recognize the urgency of incorporating opportunity costs into conservation planning. Despite this, applications to date have been limited, perhaps partly because of the difficulty in determining costs in regions with limited data on land prices and ownership. We present methods for estimating opportunity costs of land preservation in landscapes or ecoregions that are a changing mix of agriculture and natural habitat. Our approach derives from the literature on estimating land values as opportunity costs of alternate land uses and takes advantage of general availability of necessary data, even in relatively data-poor regions. The methods integrate probabilities of habitat conversion with region-wide estimates of economic benefits from agricultural land uses and estimate land values with a discount rate to convert annual values into net present values. We applied our method in a landscape undergoing agricultural conversion in Paraguay. Our model of opportunity costs predicted an independent data set of land values and was consistent with implicit discount rates of 15-25%. Model-generated land values were strongly correlated with actual land values even after correcting for the effect of property size and proportion of property that was forested. We used the model to produce a map of opportunity costs and to estimate the costs of conserving forest within two proposed corridors in the landscape. This method can be applied to conservation planning in situations where natural habitat is currently being converted to market-oriented land uses. Incorporating not only biological attributes but also socioeconomic data can help in the design of efficient networks of protected areas that represent biodiversity at minimum costs.

Economic research on biodiversity conservation has focused on the costs of conservation reserves and the benefits of intact ecosystems; however, no study has simultaneously considered the costs and benefits of species diversity, a fundamental component of biodiversity. We quantified the costs and benefits of avian biodiversity at a rainforest reserve in Uganda through a combination of economic surveys of tourists, spatial land-use analyses, and species-area relationships. Our results show that revising entrance fees and redistributing ecotourism revenues would protect 114 of 143 forest bird species (80%) under current market conditions. This total would increase to 131 species (≈90%) if entrance fees were optimized to capture the tourist's willingness to pay for forest visits and the chance of seeing increased numbers of bird species. In contrast, the cost of purchasing agricultural land for ecological rehabilitation of the avian habitat would be economically prohibitive. These results suggest that local biodiversity markets could play a positive role in tropical conservation strategies if the appropriate institutions for redistribution can be developed.

Background Despite numerous programs to combat the global HIV and AIDS pandemic, infection rates remain high, especially in sub-Saharan Africa, where two-thirds of all people living with HIV reside. Here, we describe how we used rigorous program evaluation methods to assess the effectiveness of a community-based natural resource management program that “mainstreamed” HIV awareness and prevention activities within rural communities in Namibia. Findings We used data from two rounds of the Namibia Demographic and Health Surveys (2000 and 2006/2007) and quasi-experimental statistical methods to evaluate changes in critical health-related outcomes in men and women living in communal conservancies, relative to several non-conservancy comparison groups. Our final dataset included 117 men and 318 women in 2000, and 170 men and 357 women in 2006/2007. We evaluated the statistical significance of the main effects of survey year and conservancy residence, and a conservancy-year interaction term, using generalized linear models. Our analyses show that community-based conservation in Namibia has significantly reduced multiple sexual partnerships, the main behavioural determinant of HIV/AIDS infection in Africa. Conclusions Our results demonstrate the effectiveness of holistic community-based approaches centered on the preservation of lives and livelihoods, and highlight the potential benefits of integrating conservation and HIV prevention programming in other areas of communal land tenure in Africa.

Despite the connections between terrestrial and marine/freshwater livelihood strategies that we see in coastal regions across the world, the contribution of wild fisheries and fish farming is seldom considered in analyses of the global food system and is consequently underrepresented in major food security and nutrition policy initiatives. Understanding the degree to which farmers also consume fish, and how fishers also grow crops, would help to inform more resilient food security interventions. By compiling a dataset for 123,730 households across 6781 sampling clusters in 12 highly food-insecure countries, we find that between 10 and 45% of the population relies on fish for a core part of their diet. In four of our sample countries, fish-reliant households are poorer than their counterparts. Five countries show the opposite result, with fish-reliant households having higher household asset wealth. We also find that in all but two countries, fish-reliant households depend on land for farming just as much as do households not reliant on fish. These results highlight the need for food security interventions that combine terrestrial and marine/freshwater programming if we are going to be successful in building a more resilient food system for the world’s most vulnerable people.