Bayesian Belief Networks as a tool for evidence-based conservation management

Effective conservation management is dependent on accessing and integrating different forms of evidence regarding the potential impacts of management interventions. Here, we explore the application of Bayesian Belief Networks (BBN), which are graphical models that incorporate probabilistic relationships among variables of interest, to evidence-based conservation management. We consider four case studies, namely: (i) impacts of deer grazing on saltmarsh vegetation; (ii) impacts of burning on upland bog vegetation; (iii) control of the invasive exotic plant Rhododendron ponticum; and (iv) management of lowland heathland by burning. Each of these themes is currently a significant conservation issue in the UK, and yet the potential outcomes of management interventions are poorly understood. Through these examples, we demonstrate that BBNs can be used to integrate and explore evidence from a variety of sources, including expert opinion and quantitative results from research investigations. Incorporation of such information in BBNs enables different sources of evidence to be compared, the potential impacts of management interventions to be explored and management trade-offs to be identified. BBNs also offer a highly visual tool for communicating the uncertainty associated with potential management outcomes to conservation practitioners, and they can also be readily updated as new evidence becomes available. Based on these features, we suggest that BBNs have outstanding potential for supporting evidence-based approaches to conservation management.     

Maintaining customary harvesting of freshwater resources: sustainable Indigenous livelihoods in the floodplains of northern Australia

Freshwater resources underpin multiple livelihood systems around the world, particularly in highly productive tropical floodplain regions. Sustaining Indigenous people’s access to freshwater resources for customary harvesting, while developing alternative livelihood strategies can be challenging. The sustainable livelihoods approach was applied to examine the ways in which multiple livelihoods in the East Alligator River floodplain region in northern Australia influence Aboriginal people’s access to freshwater resources for customary harvesting. Interviews with Aboriginal residents were conducted to understand changes to freshwater customary harvesting practices. The dominant floodplain-based livelihoods analysed were pastoralism, biodiversity conservation and tourism and they were found to generate both opportunities and constraints for sustaining freshwater customary harvesting. Opportunities were provided through facilitating regular access to floodplain country and opportunistic access for harvesting, which assists in sustaining bio-cultural knowledge. Partnerships developed through these mainstream livelihoods built human capacity that enhanced all livelihood resource capitals (natural, human, social, financial and physical). Three key ways the dominant livelihoods constrained access to key freshwater resources were identified. Tourism required sacrificing certain hunting places and had to accommodate recreational fishing pressure. The successful recovery of the saltwater crocodile population through biodiversity conservation policy has inadvertently reduced people’s customary access to in-stream resources. Pastoralism on the floodplain had restricted traditional floodplain burning practices associated with accessing aestivating long-necked turtles, affecting access and abundance. These findings highlight the need for the development of remote Indigenous livelihood strategies to make explicit their influences on freshwater customary harvesting practices, to better support their maintenance amongst multiple, non-customary floodplain livelihoods.     

How good are Bayesian belief networks for environmental management? A test with data from an agricultural river catchment

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Gender Differentiated Preferences for a Community-Based Conservation Initiative

Community-based conservation (CBC) aims to benefit local people as well as to achieve conservation goals, but has been criticised for taking a simplistic view of “community” and failing to recognise differences in the preferences and motivations of community members. We explore this heterogeneity in the context of Kenya’s conservancies, focussing on the livelihood preferences of men and women living adjacent to the Maasai Mara National Reserve. Using a discrete choice experiment we quantify the preferences of local community members for key components of their livelihoods and conservancy design, differentiating between men and women and existing conservancy members and non-members. While Maasai preference for pastoralism remains strong, non-livestock-based livelihood activities are also highly valued and there was substantial differentiation in preferences between individuals. Involvement with conservancies was generally perceived to be positive, but only if households were able to retain some land for other purposes. Women placed greater value on conservancy membership, but substantially less value on wage income, while existing conservancy members valued both conservancy membership and livestock more highly than did non-members. Our findings suggest that conservancies can make a positive contribution to livelihoods, but care must be taken to ensure that they do not unintentionally disadvantage any groups. We argue that conservation should pay greater attention to individual-level differences in preferences when designing interventions in order to achieve fairer and more sustainable outcomes for members of local communities.     

Modelling informal Sand Forest harvesting using a Disturbance Index from Landsat,in Maputaland (South Africa)

Indigenous forests and savannah provide numerous benefits for rural communities and are utilised as a source of firewood, building material and for woodcraft production. Currently, there is insufficient information on the magnitude of human pressure affecting one such important forest community, namely Sand Forest, particularly in communal areas. The temporal monitoring of the spatial structures of forest areas, such as Sand Forest, within landscapes has been recommended in order to detect and model deteriorating trends in the forest structures and functioning. Remote sensing is critical in the generation of data that enables the identification and quantification of degraded and deforested areas.The constrained distribution and fragmented patches associated with Sand Forest, and the effects of a declining canopy closure, resulting from selective wood harvesting, requires the use of remote sensing techniques and procedures that could potentially account for these characteristics. A spectral index that has been widely successful in monitoring disturbances in forests is the Disturbance Index. The success of the Disturbance Index in detecting changes could be attributed to the components that comprise the Disturbance Index, in that it takes into account the relationship that exists between soil; vegetation; and canopy & soil moisture. The suitability of determining changes could also be attributed to the approach taken by the Disturbance Index i.e. monitoring disturbance versus a component of vegetation, such as the Normalised Difference Vegetation Index (biomass). The rates of change derived for the study period (1998 to 2014) provided quantified information on the magnitude of human pressure affecting Sand Forest throughout Maputaland. The rates of change showed that the accumulated total loss in the extent of Sand Forest, across the South African section of Maputaland, was 15.53 km² over a period of 16 years.     

Assessing Local Knowledge of Game Abundance and Persistence of Hunting Livelihoods in the Bolivian Amazon Using Consensus Analysis

We used cultural consensus models to test whether hunters shared perceptions of wildlife abundance and the relative importance of hunting and fishing in a Guarayo indigenous community in the Bolivian Amazon. Results show that highly prized animals that were considered rare are either those with lower reproductive rates and more sensitivity to land use changes and harvest (white-lipped peccary and spider monkey) or those with marked seasonal distribution patterns (barred sorubim and tiger-fish). Rapidly reproducing and resilient species (agouti and armored catfish) were perceived as abundant. More tapirs and red brocket deer were present than predicted by scientific models possibly because hunters were harvesting these species in new forest management areas. Residents identified hunting and fishing among their most important livelihood activities, recognized bush meat and fish as basic food resources, and expected wildlife harvests to be part of their future livelihoods, although market-based livelihoods and domestic replacements for bush meat were reported.     

Ecological outcomes and livelihood benefits of community‐managed agroforests and second growth forests in Southeast Brazil

The Forest and Landscape Restoration movement has emerged as an approach to reconcile biodiversity conservation, ecosystem services provisioning and human well‐being in degraded landscapes, but little is known so far about the potential of different reforestation methods to achieve these objectives. Based on this gap, we assessed the ecological outcomes and local livelihood benefits of community‐managed agroforests and second growth forests to assist natural regeneration in the coastal Atlantic Forest of Brazil. We investigated and compared agroforests and secondary forests according to their structure and floristic composition in 51 circular plots of 314 m², their role in supporting local livelihoods (45 semi‐structured interviews) and the use and cultural importance of plant species (61 interviews). Agroforests and, more remarkably, managed secondary forests (1) re‐established a well‐developed forest structure, with a higher density of tree‐sized individuals and similar basal area compared to nearby old growth forests; (2) were composed by a rich array of native species, including five threatened species, but had lower species richness than old growth remnants; and (3) improved local livelihoods by supplying market valuable and culturally important plants, including 231 native ethnospecies. Overall, local production systems showed remarkable potential to engage smallholders of developing tropical countries in Forest and Landscape Restoration and contribute to achieve its overall goals. We advocate the promotion of these systems as effective Forest and Landscape Restoration approaches in multi‐scale programs and policies.     

The complexity of the conservation-development nexus in Central African national parks and the perceptions of local populations

Conservation programmes of recent decades aimed to adopt an approach that addresses biodiversity conservation goals through socio-economic tools and to better integrate the human dimension into biodiversity conservation. Yet, to analyse this complex conservation-development nexus, studying conservation perceptions of local populations are crucial to understand the dynamics and establish sound conservation-development management policies. Therefore, we aim to identify the key determinants of conservation perceptions in the Central African context in order to implement successful local and regional conservation strategies. Conservation perceptions of two national parks’ adjacent populations were examined through household surveys, adapted from the Poverty-Environment Network (PEN), in Rwanda and Republic of Congo. Outcomes were statistically analysed to identify the most important factors affecting perceptions about conservation measures. Using a nonlinear canonical correlation analysis, we found that economic factors (e.g. salary, savings, cattle size) and education positively affect conservation perceptions while ecosystem-dependent factors such as hunting and gathering other non-timber forest products have negative effects. Though, we identified a significant difference between two sites, whereby, conservation perceptions are negatively affected by bushmeat factors in Republic of Congo, and NTFP in Rwanda. In addition, our study showed that resource use and rights play a major role in communities’ perceptions and that revenue-sharing projects have a key impact on the perceptions. To ensure sound conservation and development measures, revenue-sharing schemes focusing on material benefits and alternative livelihoods may provide the best approach if participation of communities in the decision-making process is ensured. In this optic, improving education levels will raise awareness and positive perceptions of conservation measures. Development measures should target poor households as they appear to be more conservation-adverse. We conclude that in depth research on local demands for ecosystem products, relationships among stakeholders and community decision power are crucial factors to understand the complexity of the conservation-development nexus.     

The effects of herbivory by a mega- and mesoherbivore on tree recruitment in sand forest, South Africa

Herbivory by megaherbivores on woody vegetation in general is well documented; however studies focusing on the individual browsing effects of both mega- and mesoherbivore species on recruitment are scarce. We determined these effects for elephant Loxodonta africana and nyala Tragelaphus angasii in the critically endangered Sand Forest, which is restricted to east southern Africa, and is conserved mainly in small reserves with high herbivore densities. Replicated experimental treatments (400 m(2)) in a single forest patch were used to exclude elephant, or both elephant and nyala. In each treatment, all woody individuals were identified to species and number of stems, diameter and height were recorded. Results of changes after two years are presented. Individual tree and stem densities had increased in absence of nyala and elephant. Seedling recruitment (based on height and diameter) was inhibited by nyala, and by elephant and nyala in combination, thereby preventing recruitment into the sapling stage. Neither nyala or elephant significantly reduced sapling densities. Excluding both elephant and nyala in combination enhanced recruitment of woody species, as seedling densities increased, indicating that forest regeneration is impacted by both mega- and mesoherbivores. The Sand Forest tree community approached an inverse J-shaped curve, with the highest abundance in the smaller size classes. However, the larger characteristic tree species in particular, such as Newtonia hildebrandtii, were missing cohorts in the middle size classes. When setting management goals to conserve habitats of key importance, conservation management plans need to consider the total herbivore assemblage present and the resulting browsing effects on vegetation. Especially in Africa, where the broadest suite of megaherbivores still persists, and which is currently dealing with the 'elephant problem', the individual effects of different herbivore species on recruitment and dynamics of forests and woodlands are important issues which need conclusive answers.     

The effect of herbivores and humans on the Sand Forest species of Maputaland,northern KwaZulu-Natal,South Africa

Sand Forest in the Maputaland region of KwaZulu-Natal in South Africa is deemed the most valuable, but also probably the most complex vegetation type of this part of the Maputaland–Pondoland–Albany hotspot of biodiversity. However, Sand Forest is under threat from the current human population growth in that region as well as from uncontrolled increases in wild herbivore numbers in conservation areas. The present study compares the impacts of herbivores and humans on the state of woody resources between two sites under differing utilisation regimes. Sand Forest was found to be a complex association of tree assemblages defined by different canopy and subcanopy properties. Although marked differences in the abundance of selected species were noted at the two sites, the Sand Forest remained dominated by fine-grained species under both utilisation regimes. The fine-grained nature of Sand Forest implies that regeneration depends on the creation of small canopy gaps either by natural processes, humans or elephants, while the creation of large gaps could transform it into woodland. Management of conservation areas where Sand Forest occurs should therefore concentrate efforts on regulating animal populations to levels that provide gap properties that favour forest regeneration.     

劳动力转移和森林管护水平对森林碳密度的影响——基于福建253个村的实证研究

森林生态系统具有重要的固碳功能,有效的森林管理是提升碳密度的重要方式。随着农村劳动力转移,森林管护水平也随之变化,进而可能影响森林碳密度。为了厘清劳动力转移和森林管护水平对森林碳密度的作用机理,以提升森林碳密度。利用福建5县（区）253个村1999年与2009年的林业二类调查数据和入村调研数据,采用转换因子连续函数法评价了森林碳密度,再运用层次回归模型分析了劳动转移对森林碳密度的影响,并检验了森林管护水平对二者的中介作用。结果表明：（1）10年间森林碳密度普遍提升,但区域差异明显;空间上森林碳密度呈由南向北递增,提升率呈由南向北递减。（2）劳动力转移对森林碳密度有显著促进作用,而森林管护水平对森林碳密度有显著削弱作用,并对劳动力转移与森林碳密度之间的关系具有显著中介效应。（3）劳动力特征、采伐方式及森林自然禀赋等因素,主要通过生计依赖、生境状况和生物量对森林碳密度产生显著影响。据此提出：适当减少对森林的人为干扰,丰富林农生计来源,转变林业经营目标,科学采伐成熟和过熟林,保护天然起源林,丰富人工林树种等政策建议。     

Forest protection in Central India: do differences in monitoring by state and local institutions result in diverse social and ecological impacts?

Protection of forests and wildlife outside protected areas (PAs) is necessary for the conservation of wildlife. Extension of conservation efforts outside the existing PA may result in restrictions on local forest resource use. Such situations arise due to differences in understanding of forest as a resource for communities and as a conservation space for endangered species. A clearer focus is needed on the functionality and socio-ecological outcomes of different forest management institutions to address such issues. We conducted a study in a forest landscape connecting Pench and Tadoba-Andhari Tiger Reserves (TRs) in Central India. The two main forest management institutions were the Forest Department (FD) and local communities managing forest resources. We conducted vegetation surveys and focus group discussions in 15 villages selected based on presence or absence of active protection and monitoring of forest resources by either FD or local people. We found that forests with monitoring had significantly higher tree density and vegetation species richness compared to forests without monitoring. Tree density was observed to be higher in sites monitored by villagers rather than those monitored by FD. Self-regulation and resource sharing in locally monitored forests were more acceptable to local communities. In forests monitored by the FD, local communities indicated a feeling of alienation from the forest that weakened their motivation to protect the forest and wildlife. Recognition of local community rights is essential to achieve conservation goals and reduce social conflicts outside PAs, requiring collaboration between state and local institutions.     

Livelihoods and Fisheries Governance in a Contemporary Pacific Island Setting

Inshore marine resources play an important role in the livelihoods of Pacific Island coastal communities. However, such reliance can be detrimental to inshore marine ecosystems. Understanding the livelihoods of coastal communities is important for devising relevant and effective fisheries management strategies. Semi-structured household interviews were conducted with householders in Langalanga Lagoon, Solomon Islands, to understand household livelihoods and resource governance in fishing-dependent communities. Households were engaged in a diverse range of livelihoods. Fishing, shell money production and gardening were the most important livelihoods. Proximity to an urban centre influenced how households accessed some livelihoods. Perceptions of management rules varied and different reasons were cited for why rules were broken, the most common reason being to meet livelihood needs. Current models of inshore small-scale fisheries management that are based on the notion of community-based resource management may not work in locations where customary management systems are weak and livelihoods are heavily reliant on marine resources. An important step for fisheries management in such locations should include elucidating community priorities through participatory development planning, taking into consideration livelihoods as well as governance and development aspirations.     

Visions from Local Populations for Livelihood-Based Solutions to Promote Forest Conservation Sustainability in the Congo Basin

Forest management practices that aim to mitigate the threats of deforestation and forest degradation can inadvertently threaten the ability of forest-dependent local populations to meet basic daily sustenance needs. Stakeholder engagement can help find common ground between environmental goals and the livelihood needs of local populations. A starting point for local stakeholder engagement is to gather insights into how forest management differentially impacts the livelihoods and well-being of these populations, which may be quite heterogeneous in their perspectives and livelihood needs. Towards this end, we conducted semi-structured first-person interviews in forest-dependent communities in Cameroon about perspectives on and suggestions about forest resources and management. This study provides insights into commonalities and differences of perspectives within and among local populations and supports the use of stakeholder engagement strategies that facilitate bidirectional communication and take into consideration diverse perspectives and priorities.     

滇西北藏区自然圣境与传统文化驱动下的生物多样性保护

本研究旨在将滇西北藏区传统生态文化应用于社区生物多样性保护之中, 以推动社区参与式生物多样性保护和森林生态系统的修复。应用民族植物学和民族生态学的方法, 调查了位于白马雪山国家级自然保护区及周边地区的3个藏族村寨(巴珠、柯功、追达)的自然圣境与生物多样性分布状况及其生态服务功能等, 应用SWOT分析法和社区参与式保护途径, 开展了生物多样性保护示范活动。本研究结果表明, 社区保护生物多样性的主要驱动力来源于民族传统文化, 社区生计依赖于生物多样性, 保护自然圣境是社区水平保护生物与文化多样性及社区发展的重要途径。藏族自然圣境是基于传统信仰文化并经过长期实践建立和发展起来的有利于生物多样性保护的社区保护形式, 藏民社区长期遵从和实践自然圣境对生物多样性保护做出了重要贡献。     

The paraty artisanal fishery (southeastern Brazilian coast): ethnoecology and management of a social-ecological system (SES)

ABSTRACT: This study intends to give recommendations to the management of Paraty fishery in Brazil through an interplay of local and scientific knowledge. In particular, the objectives are the following: 1) to describe the Paraty fishery; 2) to compare the fishermen's local ecological knowledge with recorded fish landings and previous studies in Paraty; 3) to combine the data on local fishing and on local/Caicara livelihoods with the SES (social-ecological systems) Model. The methods include a systematic survey of fishing in Tarituba and Praia Grande, which are located in the northern end and the central part of the Paraty municipality, respectively. For four days each month, systematic data on catches at landing points were collected, as well as macroscopic gonad analysis data for the fishes Centropomus parallelus and C. undecimalis (snook, robalo), Epinephelus marginatus (grouper, garoupa), Scomberomorus cavalla (King mackerel, cavala), and Lutjanus synagris (Lane snapper, vermelho). Spring and summer are important seasons during which some species reproduce, and the integration of fishing periods for some target species could assist in fishing management through the use of closed seasons. Fishermen could obtain complementary earnings from tourism and from the "defeso system" (closed season including a salary payment) to conserve fishing stocks. The SES model facilitates an understanding of the historical context of fishing, its economic importance for local livelihoods, the constraints from conservation measures that affect fishermen, and the management processes that already exist, such as the defeso. If used to integrate fishing with complementary activities (tourism), such a system could improve the responsibility of fishermen regarding the conservation of fish stocks.     

Diversifying Incomes and Losing Landscape Complexity in Quilombola Shifting Cultivation Communities of the Atlantic Rainforest (Brazil)

Shifting cultivation systems have been blamed as the primary cause of tropical deforestation and are being transformed through various forms of conservation and development policies and through the emergence of new markets for cash crops. Here, we analyze the outcomes of different policies on land use/land cover change (LUCC) in a traditional, shifting cultivation landscape in the Atlantic Forest (Brazil), one of the world’s top biodiversity hotspots. We also investigate the impacts of those policies on the environment and local livelihoods in Quilombola communities, which are formed by descendants of former Maroon colonies. Our findings show that conservation and social policies have had mixed effects both on the conservation of the Atlantic Forest and on the livelihoods of the Quilombola. We conclude that future interventions in the region need to build on the new, functional links between sustainable livelihoods and biodiversity, where less restrictive state policies leave room for new opportunities in self-organization and innovation.     

A community perspective on participatory conservation in western Tanzania

Local participation is a key component of sound management of protected areas. The starting point for achieving this goal is to establish factors influencing it. In the Ugalla ecosystem of western Tanzania, the government in collaboration with other conservation organisations has initiated efforts to engage local people in conservation. However, the area is under increasing pressure especially from local livelihood activities and exploitation of natural resources. This study used focus group discussions and key informants to explore factors that would promote local engagement in conservation. Fifty-two activities were mentioned and ranked in terms of their effectiveness in reducing illegal use of natural resources. Improving household-level livelihoods ranked highest, followed by improving subsistence agriculture and stopping game rangers from harassing villagers. Reducing land use conflicts between local people and conservation authorities was also commonly mentioned. Capacity building and alternative sources of livelihood cannot be overstated. Additionally, Ugalla should be managed appropriately and transparently, and used effectively to improve participatory conservation. Overall, local communities were interested in a participatory conservation that would strike a fair balance between the improvement of their living standards and the conservation of natural resources. Further, research should include household interviews to reveal household level factors that affect participation in conservation.     

Constraints and Opportunities for Sustainable Livelihoods and Cash Income Generation from NTFPs in the Mountains of Northern Parts of Pakistan

Pakistan′s forest resource base is mostly found in the mountains of the North-West Frontier Province (NWFP) supporting the livelihood of the rural poor and providing different ecological services. The present study was, therefore, initiated with the aim to evaluate different constraints and opportunities for sustainable livelihoods and cash income generation from NTFPs in the mountainous area of NWFP, Pakistan during 2008. Information was collected through questionnaire and interviews during field trips. A total of 117 NTFPs species have been recorded which are being used locally for various purposes such as fuel wood, fodder, medicinal plants, vegetables, mushroom, agricultural tools making, furniture, thatching, shade, fencing/ poles, ornamental purpose and animal products. The majority of plants are multi-functional like Pinus wallichiana provides timber, firewood, torch wood, the leaves/small branches are used as thatch for roofing, split logs are used for fencing and the decomposed needles are collected as humus for agricultural fields. These products were widely used by the indigenous community supporting their livelihood. The study proposes protection and sustainable management of these valuable resources for rural livelihoods, which might be useful for developing regional strategies of sustainable management of forest resources.     

Using Bayesian networks to incorporate uncertainty in habitat suitability index models

Habitat suitability index (HSI) models rarely characterize the uncertainty associated with their estimates of habitat quality despite the fact that uncertainty can have important management implications. The purpose of this paper was to explore the use of Bayesian belief networks (BBNs) for representing and propagating 3 types of uncertainty in HSI models—uncertainty in the suitability index relationships, the parameters of the HSI equation, and measurement of habitat variables (i.e., model inputs). I constructed a BBN–HSI model, based on an existing HSI model, using Netica™ software. I parameterized the BBN's conditional probability tables via Monte Carlo methods, and developed a discretization scheme that met specifications for numerical error. I applied the model to both real and dummy sites in order to demonstrate the utility of the BBN–HSI model for 1) determining whether sites with different habitat types had statistically significant differences in HSI, and 2) making decisions based on rules that reflect different attitudes toward risk—maximum expected value, maximin, and maximax. I also examined effects of uncertainty in the habitat variables on the model's output. Some sites with different habitat types had different values for E[HSI], the expected value of HSI, but habitat suitability was not significantly different based on the overlap of 90% confidence intervals for E[HSI]. The different decision rules resulted in different rankings of sites, and hence, different decisions based on risk. As measurement uncertainty in habitat variables increased, sites with significantly different (α = 0.1) E[HSI] became statistically more similar. Incorporating uncertainty in HSI models enables explicit consideration of risk and more robust habitat management decisions. © 2012 The Wildlife Society.