Warfare in Biodiversity Hotspots

Abstract:  Conservation efforts are only as sustainable as the social and political context within which they take place. The weakening or collapse of sociopolitical frameworks during wartime can lead to habitat destruction and the erosion of conservation policies, but in some cases, may also confer ecological benefits through altered settlement patterns and reduced resource exploitation. Over 90% of the major armed conflicts between 1950 and 2000 occurred within countries containing biodiversity hotspots, and more than 80% took place directly within hotspot areas. Less than one-third of the 34 recognized hotspots escaped significant conflict during this period, and most suffered repeated episodes of violence. This pattern was remarkably consistent over these 5 decades. Evidence from the war-torn Eastern Afromontane hotspot suggests that biodiversity conservation is improved when international nongovernmental organizations support local protected area staff and remain engaged throughout the conflict. With biodiversity hotspots concentrated in politically volatile regions, the conservation community must maintain continuous involvement during periods of war, and biodiversity conservation should be incorporated into military, reconstruction, and humanitarian programs in the world's conflict zones.     

Can Extractive Reserves Save the Rain Forest? An Ecological and Socioeconomic Comparison of Nontimber Forest Product Extraction Systems in Petén,Guatemala, and West Kalimantan,Indonesia

We compare existing nontimber forest product extraction systems in Petén, Guatemala, and West Kalimantan, Indonesia, to identify key ecological, socioeconomic, and political factors in the design and implementation of extractive reserves. Ecological parameters include the spatial and temporal availability of harvested products and the sustainability of harvesting practices from both a population and an ecosystem perspective. Socioeconomic and political factors include the presence or absence of well-defined resource tenure rights, physical and social infrastructure, markets, and alternative land uses. We conclude that although extractive reserves can play a significant role in preserving tropical forests as a part of a broader land-use spectrum, their effectiveness is highly dependent on prevailing local ecological, socioeconomic, and political conditions. Ultimately, extractive reserves should be regarded as one component of an overall approach to the problem of tropical deforestation.     

Conservation and Community Benefits from Traditional Coral Reef Management at Ahus Island, Papua New Guinea

Abstract:  We investigated traditional coral reef management practices at Ahus Island, Manus Province, Papua New Guinea, to evaluate their social role in the community and potential to conserve reef ecosystems. For generations, Ahus Islanders have prohibited spear and net fishing within six delineated areas of their reef lagoon. One to three times per year, fish are briefly harvested from the restricted areas to provide food for ceremonial occasions. Underwater visual censuses of fishes revealed a significantly greater biomass and average size of target species within the restricted areas (205 kg/ha ± 20 [SE]; 102 mm TL [total length]± 0.7) compared with areas without fishing restrictions (127 kg/ha ± 13 SE; 85 mm TL ± 0.7). We estimated the biomass of fish removed during one of the harvest events was 5 to 10% of the available biomass within the restricted area, and in underwater visual surveys conducted before and after a harvesting event we detected no effect of harvesting on fish stocks. Compliance with the fishing restriction is attributed to its perceived legitimacy, its ability to provide the community with direct and indirect benefits, and its reflection of local socioeconomic circumstances. Limited-take closure systems that can serve the needs of a community may provide a viable conservation alternative in situations where compliance with fully closed protected-area regulations is low and resources for proper enforcement are untenable.     

A density projection approach for non-trivial information dynamics: Adaptive management of stochastic natural resources

We demonstrate a density projection approximation method for solving resource management problems with imperfect state information. The method expands the set of partially-observed Markov decision process (POMDP) problems that can be solved with standard dynamic programming tools by addressing dimensionality problems in the decision maker's belief state. Density projection is suitable for uncertainty over both physical states (e.g. resource stock) and process structure (e.g. biophysical parameters). We apply the method to an adaptive management problem under structural uncertainty in which a fishery manager's harvest policy affects both the stock of fish and the belief state about the process governing reproduction. We solve for the optimal endogenous learning policy—the active adaptive management approach—and compare it to passive learning and non-learning strategies. We demonstrate how learning improves efficiency but typically follows a period of costly short-run investment.     

Assessment of traditional rights,local interference and natural resource management in Kedarnath Wildlife Sanctuary

An assessment of human interference in Kedarnath Wildlife Sanctuary (KWLS) showed huge dependence of local communities on forest fringes. KWLS is under active consideration as a national park because of its unique flora and fauna. Studies have evidenced habitat destruction and successional changes in the area because of ongoing unsustainable harvesting and logging. The present study provides an integrated approach towards evaluating resource extraction and management of the sanctuary. The study was based on in-depth semi-structured interviews and group discussions with local inhabitants of six villages and with forest officials. In addition, regeneration patterns and vegetation analysis was conducted in three land tenurial systems: community forest (CF), reserve forest (RF) and protected forest (PF). Key issues identified were wildlife offences, encroachment, pressure from unsustainable harvesting of resources and lack of livelihood opportunities. Ecological studies showed continuous change in regeneration patterns in forest patches/stands. The local survey stressed managing sanctuary fringes considering the village economy, social issues and resource requirements, and enhancing on-farm resource production to reduce pressure on forests. Forest personnel demanded more training on encroachment and poaching, these being major threats to biodiversity and bio-resources. Supporting and providing better livelihood opportunities is a viable option for minimizing pressure and managing biodiversity of the area through active community participation. This study generated useful outcomes and strategies for advancing policies to reduce pressure and overcome management constraints in the sanctuary.     

Salvage Logging, Ecosystem Processes, and Biodiversity Conservation

Abstract:  We summarize the documented and potential impacts of salvage logging—a form of logging that removes trees and other biological material from sites after natural disturbance. Such operations may reduce or eliminate biological legacies, modify rare postdisturbance habitats, influence populations, alter community composition, impair natural vegetation recovery, facilitate the colonization of invasive species, alter soil properties and nutrient levels, increase erosion, modify hydrological regimes and aquatic ecosystems, and alter patterns of landscape heterogeneity. These impacts can be assigned to three broad and interrelated effects: (1) altered stand structural complexity; (2) altered ecosystem processes and functions; and (3) altered populations of species and community composition. Some impacts may be different from or additional to the effects of traditional logging that is not preceded by a large natural disturbance because the conditions before, during, and after salvage logging may differ from those that characterize traditional timber harvesting. The potential impacts of salvage logging often have been overlooked, partly because the processes of ecosystem recovery after natural disturbance are still poorly understood and partly because potential cumulative effects of natural and human disturbance have not been well documented. Ecologically informed policies regarding salvage logging are needed prior to major natural disturbances so that when they occur ad hoc and crisis-mode decision making can be avoided. These policies should lead to salvage-exemption zones and limits on the amounts of disturbance-derived biological legacies (e.g., burned trees, logs) that are removed where salvage logging takes place. Finally, we believe new terminology is needed. The word salvage implies that something is being saved or recovered, whereas from an ecological perspective this is rarely the case.     

Conservation and Management of a Threatened Madagascar Palm Species, Neodypsis decaryi, Jumelle

The dynamics of a remnant population of the palm Neodypsis decaryi were characterized using a linear, stage-structured demographic model. This palm is a threatened keystone species restricted to a narrow ecological zone in southeastern Madagascar. The population showed high mortality rates in the early stages of the life cycle, followed by a period of lower adult mortality. Demographic results indicated that the population was either stable or increasing inside the reserve (λ _m close to 1.0). Sensitivity and elasticity analyses indicated that adult stage classes were the most sensitive to producing changes in population growth rates. Continued biological monitoring is appropriate for the long-term conservation management of this palm inside the reserve. Outside the protected area the population appears to be declining rapidly, mainly because of anthropogenic effects (especially fire and grazing). If the conservation of Neodypsis decaryi is to be successful in the long term, then conservation methods must be carried out in cooperation with local villagers, and the species should be managed as a renewable resource in situ and ex situ. In situ conservation should include cultivation of this species throughout its natural range and protection of the existing viable natural populations. Alternative conservation management practices, both ecologically and economically sustainable, may be useful to alleviate the human pressures on this renewable resource. If leaves of N. decaryi are to be harvested by local people, we recommend restricting annual harvesting to about 25% of leaves per tree per year. Based on sensitivity analysis, seed collection should be kept well below 95% of the yearly crop if harvesting is not to have a significant impact on population growth rates.     

Dissecting the tragedy: A spatial model of behavior in the commons

Much of the discussion of the tragedy of the commons focuses on aggregate impacts, often in data-poor developing country settings. Few non-experimental empirical studies shed light on contextual circumstances driving the extent of rent dissipation and overexploitation. We utilize a high-resolution data set to estimate a behavioral model of fishermen's spatial choices. A unique policy setting allows us to measure the degree to which individual fishermen's choices appear aimed at mitigating the tragedy of the commons in a small numbers setting. We find evidence of partial mitigation in excess of what we would expect under pure self-interest but short of what would occur under group-maximizing behavior. We also examine how contextual factors in the fishery shape the degree of cooperation within the fishing season and find evidence that competition for the common pool resource distorts fishermen's implicit cost of distance—creating a form of “common property inertia”.     

Coalition formation in fisheries with potential regime shift

A system can undergo rapid regime shift in which the growth of natural resources suddenly and permanently declines. We examine how the threat of such a shift alters the strategic management of a common pool renewable resource. We consider exogenous and endogenous threats and examine their effects on both incentives to join a coalition and harvest decisions. We find that an exogenous threat of reduced resource growth may cause the coalition to grow in size, and, perhaps of most interest, we identify conditions under which members of the stable coalition reduce harvest while non-members increase harvest in response to the threat. In contrast, an exogenous threat of total stock collapse may destabilize coalitions, resulting in higher harvest from former members, but reduced harvest by non-members. When the threat of either type of shift is endogenous, the threat of regime shift can induce stable coalitions with more than two members. In particular, we identify cases in which the first best (full cooperation) is sustained as an equilibrium outcome. Finally, we find that the relation between the magnitude of the shift and the size of stable coalitions may be negative.     

Strategic investment in reputation

Although collective efforts are common in both animal and human societies, many human and probably animal social dilemmas have no obvious cooperative solution, which is a challenge for evolutionary biologists. In public goods games, i.e. the experimental paradigm for studying the sustainability of a public resource with human subjects, initial cooperation usually declines quickly. Recently, it has been shown that the interaction with another social game in which good reputation attracts help, can maintain a high level of cooperation in the public goods game. Here we show experimentally that humans use different strategies in the public goods game conditional on whether the player knows that his decisions will be either known or unknown in another social game. The knowledge of being recognized as the same individual in both scenarios motivates players to invest in their reputation and thus sustain the public resource. However, cooperation declines immediately when individual identities switch from being recognizable to being unrecognizable between the two interacting games.Communicated by M. Borgerhoff-Mulder     

Acceptance of Scientific Management by Natural Resource Dependent Communities

We explore the reaction of two resource dependent communities, west Texas ranchers and Gulf Coast oyster fishers, to scientific resource management. We examine the criteria these two social groups use to judge scientific claims, and by extension, scientific resource management. Although scientists rely on factors internal to the scientific enterprise (e.g., methodological rigor), natural resource dependent communities such as ranchers and fishers may rely on factors external to the scientific process. Such factors include the historical relationship the community has had with the managing agency, the extent to which scientific explanations match local experience, the conceptual fit between managers' and communities' views of the appropriate relationship between humans and nature, and the resources available to the community to argue against regulation. We conclude that (1) agencies should explore the possibility of including the experiential knowledge of natural resource users where applicable and (2) agencies should recognize that communication skills can be as important as scientific skills in reaching management goals.     

Demographic Side Effects of Selective Hunting in Ungulates and Carnivores

Abstract:  Selective harvesting regimes are often implemented because age and sex classes contribute differently to population dynamics and hunters show preferences associated with body size and trophy value. We reviewed the literature on how such cropping regimes affect the demography of the remaining population (here termed demographic side effects ). First, we examined the implications of removing a large proportion of a specific age or sex class. Such harvesting strategies often bias the population sex ratio toward females and reduce the mean age of males, which may consequently delay birth dates, reduce birth synchrony, delay body mass development, and alter offspring sex ratios. Second, we reviewed the side effects associated with the selective removal of relatively few specific individuals, often large trophy males. Such selective harvesting can destabilize social structures and the dominance hierarchy and may cause loss of social knowledge, sexually selected infanticide, habitat changes among reproductive females, and changes in offspring sex ratio. A common feature of many of the reported mechanisms is that they ultimately depress recruitment and in some extreme cases even cause total reproductive collapse. These effects could act additively and destabilize the dynamics of populations, thus having a stronger effect on population growth rate than first anticipated. Although more experimental than observational studies reported demographic side effects, we argue that this may reflect the quite subtle mechanisms involved, which are unlikely to be detected in observational studies without rigorous monitoring regimes. We call for more detailed studies of hunted populations with marked individuals that address how the expression of these effects varies across mating systems, habitats, and with population density. Theoretical models investigating how strongly these effects influence population growth rates are also required.     

The development of secondary industries through the sustainable utilisation of reeds and forest timber in the Tembe Elephant Park,Maputaland, South Africa

The harvesting of Phragmites australis reeds in the Tembe Elephant Park has to be managed pro-actively. Solutions to potential problems should be sought before they arise. This paper offers a potential solution to the problem of instating a winter-only reed harvest in the Muzi Swamp. The potential for manufacturing finished products such as prefabricated huts from sustainably harvested reeds and forest timber is examined and a cost estimate is presented. A prefabricated reed hut is three-times cheaper than a similarly-sized house made of bricks and cement. The manufacturing of finished products from the harvested material will add secondary value to the resource and also offer an alternative employment to harvesting reeds in the summer. The higher prices obtained for a processed article will also, hopefully, reduce the demand for the resource in its raw form, thereby increasing the perceived value of the resource and reducing wastage from raw materials that are not sold.     

Model of coral population response to accelerated bleaching and mass mortality in a changing climate

We model coral community response to bleaching and mass mortality events which are predicted to increase in frequency with climate change. The model was parameterized for the Arabian/Persian Gulf, but is generally applicable. We assume three species groups (Acropora, faviids, and Porites) in two life-stages each where the juveniles are in competition but the adults can enter a size-refuge in which they cannot be competitively displaced. An aggressive group (Acropora species) dominates at equilibrium, which is not reached due to mass mortality events that primarily disadvantage this group (compensatory mortality, >90% versus 25% in faviids and Porites) roughly every 15 years. Population parameters (N individuals, carrying capacity) were calculated from satellite imagery and in situ transects, vital rates (fecundity, mortality, and survival) were derived from the model, field observations, and literature. It is shown that populations and unaltered community structure can persist despite repeated 90% mortality, given sufficiently high fecundity of the remaining population or import from connected populations. The frequency of disturbance determines the dominant group—in low frequency Acropora, in high frequency Porites. This is congruent with field observations. The model of an isolated population was more sensitive to parameter changes than that of connected populations. Highest sensitivity was to mortality rate and recruitment rate. Community composition was sensitive to spacing of disturbances and level of catastrophic mortality. Decreased mortality led to Acropora dominance, increased mortality led to Acropora extinction. In nature, closely spaced disturbances have severely disadvantaged Acropora populations over the last decade. Unless a longer (>10 years) disturbance-free interval can be maintained, a permanent shift away from Acropora dominance will be observed. A mortality rate of 99% in Acropora, as observed in 1996, is not sustainable if repetitive and neither is a disturbance frequency <15 years—each leading to population collapse. This shows that the severity and/or the spacing of the 1996–1998–2002 disturbances were unusual in frequency and duration.     

Reframing the concept of alternative livelihoods

Alternative livelihood project (ALP) is a widely used term for interventions that aim to reduce the prevalence of activities deemed to be environmentally damaging by substituting them with lower impact livelihood activities that provide at least equivalent benefits. ALPs are widely implemented in conservation, but in 2012, an International Union for Conservation of Nature resolution called for a critical review of such projects based on concern that their effectiveness was unproven. We focused on the conceptual design of ALPs by considering their underlying assumptions. We placed ALPs within a broad category of livelihood‐focused interventions to better understand their role in conservation and their intended impacts. We dissected 3 flawed assumptions about ALPs based on the notions of substitution, the homogenous community, and impact scalability. Interventions based on flawed assumptions about people's needs, aspirations, and the factors that influence livelihood choice are unlikely to achieve conservation objectives. We therefore recommend use of a sustainable livelihoods approach to understand the role and function of environmentally damaging behaviors within livelihood strategies; differentiate between households in a community that have the greatest environmental impact and those most vulnerable to resource access restrictions to improve intervention targeting; and learn more about the social–ecological system within which household livelihood strategies are embedded. Rather than using livelihood‐focused interventions as a direct behavior‐change tool, it may be more appropriate to focus on either enhancing the existing livelihood strategies of those most vulnerable to conservation‐imposed resource access restrictions or on use of livelihood‐focused interventions that establish a clear link to conservation as a means of building good community relations. However, we recommend that the term ALP be replaced by the broader term livelihood‐focused intervention. This avoids the implicit assumption that alternatives can fully substitute for natural resource‐based livelihood activities.     

Reputation is valuable within and outside one’s own social group

To find conditions under which humans cooperate within groups of unrelated individuals has been of major interest in the behavioral sciences. The experimental paradigm for studying potential cooperation in social dilemmas is the public goods game. Here humans regularly fail to sustain a public resource cooperatively. However, the need to maintain good reputation for other social interactions, such as indirect reciprocity, has been identified as an effective mechanism to sustain cooperation in public goods situations. As a side effect of building a good reputation through cooperative actions, an individual provides direct benefits to members of his/her own social group. These benefits could be an incentive to reward a good reputation of group members. Here we show experimentally that building a good reputation through cooperative behavior in a public goods situation is rewarded in future social interactions, not only within ones own social group but also, at a similar level, in other social groups: humans regard cooperative behavior of others as an honest signal irrespective of past direct personal benefits. Reputation gained within as well as outside ones own social group can be a driving force for selfish individuals to cooperate in public goods situations, and thereby sustain any public resource.Communicated by T. Czeschlik     

Social network properties within a fish assemblage invaded by non-native sunbleak Leucaspius delineatus

Network theory is commonly used to reveal social interactions and the organisation of interconnected nodes—but has not yet been applied to animal invasions. Non-native species invasions are now considered one of the foremost threats to natural ecosystems and biodiversity. This is the first attempt to assess social network properties within a freshwater fish assemblage invaded by a non-native fish species. We show that invasive sunbleak Leucaspius delineatus is socially more strongly interconnected with native species than the native species with each other. The social networks also reveal characteristics of a ‘small world’ such as low clustering coefficients C and short path lengths L. The findings may indicate potential traits of successful invaders and the implication for the spread of pathogens between individuals within a group of animals that contain a non-native invasive species. The success of establishment and subsequent invasion may be highlighted not only by the capacity of the new species to adapt to the new environment, but also in its capacity to penetrate the social circle of the native community.     

Association patterns among wild chimpanzees (<Emphasis Type="Italic">Pan troglodytes schweinfurthii</Emphasis>) reflect sex differences in cooperation

Theory predicts that frequent dyadic association should promote cooperation through kin selection or social tolerance. Here we test the hypothesis that sex differences in the strength and stability of association preferences among free-ranging chimpanzees conform to sex differences in cooperative behavior. Using long-term data from the Kanyawara chimpanzee (Pan troglodytes schweinfurthii) community (Kibale National Park, Uganda), we calculated indices of intra-sexual dyadic association over a 10-year period. We found that (1) male–male dyads had significantly stronger association indices than female–female dyads, (2) the pattern of association preferences in both sexes changed little over the entire study period, and (3) when comparing periods with different alpha males, changes in association strength were more frequent among males. These results demonstrate that both the strength and stability of association patterns are important components of social relationships. Male chimpanzees, which are characterized by frequent cooperation, had association preferences that were both strong and stable, suggesting that forming long-term bonds is an important dominance strategy. However, the fact that male association patterns were sensitive to upheaval in the male dominance hierarchy suggests that males also take advantage of a changing social climate when choosing association partners. By contrast, the overall strength of female associations was relatively weak. Female association preferences were equally stable as males’; however, this reflected a dyad’s tendency to be found in the same party rather than to associate closely within that party. Therefore, in this community, female association patterns appear to be more a consequence of individual ranging behavior rather than a correlate of cooperation.