Free-Riding in Plant Health: A Social-Ecological Systems Approach to Collective Action.

Plant disease epidemics often transcend land management boundaries, creating a collective-action problem where a group must cooperate in a common effort to maximize individual and group benefits. Drawing upon the social-ecological systems framework and associated design principles, we review variables of resource systems, resource units, actors, and governance systems relevant to collective action in plant health. We identify a need to better characterize how attributes of epidemics determine the usefulness of collective management, what influences actors' decisions to participate, what governance systems fit different plant health threats, and how these subsystems interact to lead to plant health outcomes. We emphasize that there is not a single governance structure that ensures collective action but rather a continuum of structures that depend on the key system variables identified. An integrated social-ecological systems approach to collective action in plant health should enable institutional designs to better fit specific plant health challenges.

Pro-environmental behavior regarding single-use plastics reduction in urban-rural communities of Thailand: Implication for public policy.

The study investigates residents' behavior towards reducing the use of single-use plastic (SUP), specifically in the context of food packaging. The widespread view holds that pro-environmental behavior (PB) results from a person's moral and rational deliberations. In reducing single-use plastic (SUP) consumption and waste, the relative roles of rationality and morality models in validating PB among rural and urban residents are not yet clear. In this empirical study, we compared the relative efficacy of two models for explaining people's SUP reduction behavior: the theory of planned behavior (TPB; rationality) and the value belief norm (VBN; morality). We investigated Thailand's rural (Sichang Island) and metropolitan (Nonthaburi city) areas. As a result, we surveyed people living on Sichang Island (n = 255) and in Nonthaburi city (n = 310). We employed structural equation modeling (SEM) for data analysis in this study. Findings showed that while morality better justified all the study participants' SUP reduction behavior, rationality underpinned behaviors of rural residents, while morality better explained the actions of city residents. We discussed future theoretical development and a policy roadmap based on these findings.

Using Bayesian Belief Networks to Investigate Farmer Behavior and Policy Interventions for Improved Nitrogen Management.

Increasing farmers' adoption of sustainable nitrogen management practices is crucial for improving water quality. Yet, research to date provides ambiguous results about the most important farmer-level drivers of adoption, leaving high levels of uncertainty as to how to design policy interventions that are effective in motivating adoption. Among others, farmers' engagement in outreach or educational events is considered a promising leverage point for policy measures. This paper applies a Bayesian belief network (BBN) approach to explore the importance of drivers thought to influence adoption, run policy experiments to test the efficacy of different engagement-related interventions on increasing adoption rates, and evaluate heterogeneity of the effect of the interventions across different practices and different types of farms. The underlying data comes from a survey carried out in 2018 among farmers in the Central Valley in California. The analyses identify farm characteristics and income consistently as the most important drivers of adoption across management practices. The effect of policy measures strongly differs according to the nitrogen management practice. Innovative farmers respond better to engagement-related policy measures than more traditional farmers. Farmers with small farms show more potential for increasing engagement through policy measures than farmers with larger farms. Bayesian belief networks, in contrast to linear analysis methods, always account for the complex structure of the farm system with interdependencies among the drivers and allow for explicit predictions in new situations and various kinds of heterogeneity analyses. A methodological development is made by introducing a new validation measure for BBNs used for prediction.

Perceived Vulnerability and Propensity to Adopt Best Management Practices for Huanglongbing Disease of Citrus in California.

Huanglongbing (HLB) disease of citrus, which is associated with the bacterium 'Candidatus Liberibacter asiaticus', has been confined to residential properties in Southern California 8 years after it was first detected in the state. To prevent the spread of HLB to commercial citrus groves, growers have been asked to adopt a portfolio of voluntary best management practices. This study evaluates the citrus industry's propensity to adopt these practices using surveys and a novel multivariate ordinal regression model. We estimate the impact on adoption of perceived vulnerability to HLB, intentions to stay informed and communicate about the disease and various socio-economic factors, and reveal what practices are most likely to be jointly adopted as an integrated approach to HLB. Survey participants were in favor of scouting and surveying for HLB symptoms, but they were reluctant to test trees, use early detection technologies (EDTs), and install barriers around citrus groves. Most practices were perceived as complementary, particularly visual inspections and some combinations of preventive practices with tests and EDTs. Participants who felt more vulnerable to HLB had a higher propensity to adopt several practices, as did those who intended to stay informed and communicate with the coordinators of the HLB control program, although this effect was modulated by the perceived vulnerability to HLB. Communication with neighbors and the size of citrus operations also influenced practice adoption. Based on these results, we provide recommendations for outreach about HLB management in California and suggest future directions for research about the adoption of plant disease management practices.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Improving inferences about private land conservation by accounting for incomplete reporting.

Private lands provide key habitat for imperiled species and are core components of function protectected area networks; yet, their incorporation into national and regional conservation planning has been challenging. Identifying locations where private landowners are likely to participate in conservation initiatives can help avoid conflict and clarify trade-offs between ecological benefits and sociopolitical costs. Empirical, spatially explicit assessment of the factors associated with conservation on private land is an emerging tool for identifying future conservation opportunities. However, most data on private land conservation are voluntarily reported and incomplete, which complicates these assessments. We used a novel application of occupancy models to analyze the occurrence of conservation easements on private land. We compared multiple formulations of occupancy models with a logistic regression model to predict the locations of conservation easements based on a spatially explicit social-ecological systems framework. We combined a simulation experiment with a case study of easement data in Idaho and Montana (United States) to illustrate the utility of the occupancy framework for modeling conservation on private land. Occupancy models that explicitly accounted for variation in reporting produced estimates of predictors that were substantially less biased than estimates produced by logistic regression under all simulated conditions. Occupancy models produced estimates for the 6 predictors we evaluated in our case study that were larger in magnitude, but less certain than those produced by logistic regression. These results suggest that occupancy models result in qualitatively different inferences regarding the effects of predictors on conservation easement occurrence than logistic regression and highlight the importance of integrating variable and incomplete reporting of participation in empirical analysis of conservation initiatives. Failure to do so can lead to emphasizing the wrong social, institutional, and environmental factors that enable conservation and underestimating conservation opportunities in landscapes where social norms or institutional constraints inhibit reporting.

La incorporación de las tierras privadas a la planeación de la conservación regional y nacional ha sido un reto a pesar de su importancia como hábitat para especies en peligro y como componentes nucleares de las redes funcionales de áreas protegidas. La identificación de las localidades en donde sea probable que los propietarios privados participen en las iniciativas de conservación puede ayudar a evitar conflictos costosos y a aclarar las compensaciones entre los beneficios ecológicos y los costos sociopolíticos. La evaluación empírica y espacialmente explícita de los factores asociados con la conservación en tierras privadas es una herramienta emergente usada para la identificación de oportunidades de conservación en el futuro. Sin embargo, la mayoría de los datos sobre la conservación en tierras privadas es reportada voluntariamente y está incompleta, lo cual complica realizar estas evaluaciones. Usamos una aplicación novedosa de los modelos de ocupación para analizar la presencia de la mitigación por conservación en tierras privadas. Comparamos diferentes formulaciones de los modelos de ocupación con un modelo de regresión logística para predecir las localidades de la mitigación por conservación con base en un marco de trabajo de un sistema socioecológico espacialmente explícito. Combinamos un experimento de simulación con un estudio de caso sobre datos de mitigación en Idaho y Montana (Estados Unidos) para ilustrar la utilidad del marco de trabajo de ocupación para el modelado de la conservación en tierras privadas. Los modelos de ocupación que consideraron explícitamente la variación en los reportes produjeron estimados de los predictores que estuvieron sustancialmente menos sesgados que los estimados producidos por la regresión logística bajo todas las condiciones simuladas. Los modelos de ocupación produjeron estimaciones para seis predictores que evaluamos en nuestro estudio de caso, los cuales fueron mayores en magnitud pero menos certeros que aquellos producidos por la regresión logística. Estos resultados sugieren que los modelos de ocupación tienen como resultado inferencias cualitativamente diferentes a la regresión logística con respecto a los efectos de los predictores sobre la presencia de mitigación por conservación y resaltan la importancia de la integración de los reportes variables e incompletos sobre la participación dentro del análisis empírico de las iniciativas de conservación. Si se falla en lo anterior se puede terminar enfatizando el factor social, institucional y ambiental equivocado que permite la conservación, además de subestimar las oportunidades de conservación en paisajes en donde las normas sociales o las restricciones institucionales inhiben el reporte de datos.

Sustainability partnerships and viticulture management in California.

Agricultural regions in the United States are experimenting with sustainability partnerships that, among other goals, seek to improve growers' ability to manage their vineyards sustainably. In this paper, we analyze the association between winegrape grower participation in sustainability partnership activities and practice adoption in three winegrowing regions of California. Using data gathered from a survey of 822 winegrape growers, we find a positive association between participation and adoption of sustainable practices, which holds most strongly for practices in which the perceived private benefits outweigh the costs, and for growers with relatively dense social networks. We highlight the mechanisms by which partnerships may catalyze sustainable farm management, and discuss the implications of these findings for improving sustainability partnerships. Taken together, we provide one of the most comprehensive quantitative analyses to date regarding the effectiveness of agricultural sustainability partnerships for improving farm management.

Identifying climate risk perceptions, information needs, and barriers to information exchange among public land managers.

Meeting ecosystem management challenges posed by climate change requires building effective communication channels among researchers, planners and practitioners to focus research on management issues requiring new knowledge. We surveyed resource managers within two regions of the western United States regions to better understand perceived risks and vulnerabilities associated with climate change and barriers to obtaining and using relevant climate science information in making ecosystem management decisions. We sought to understand what types of climate science information resource managers find most valuable, and the formats in which they prefer to receive climate science information. We found broad concern among natural resource managers in federal agencies that climate change will make it more difficult for them to achieve their management goals. Primary barriers to incorporating climate science into planning are distributed among challenges identifying, receiving, and interpreting appropriate science and a lack of direction provided by agency leadership needed to meaningfully use this emerging science in resource planning.

Adaptive social strategies in a solitary carnivore.

Cost-benefit trade-offs for individuals participating in social behaviors are the basis for current theories on the evolution of social behaviors and societies. However, research on social strategies has largely ignored solitary animals, in which we assume that rare interactions are explained by courtship or territoriality or, in special circumstances, resource distributions or kinship. We used directed network analysis of conspecific tolerance at food sources to provide evidence that a solitary carnivore, the puma (Puma concolor), exhibited adaptive social strategies similar to more social animals. Every puma in our analysis participated in the network, which featured densely connected communities delineated by territorial males. Territorial males also structured social interactions among pumas. Contrary to expectations, conspecific tolerance was best characterized by direct reciprocity, establishing a fitness benefit to individuals that participated in social behaviors. However, reciprocity operated on a longer time scale than in gregarious species. Tolerance was also explained by hierarchical reciprocity, which we defined as network triangles in which one puma (generally male) received tolerance from two others (generally females) that also tolerated each other. Hierarchical reciprocity suggested that males might be cheating females; nevertheless, we suspect that males and females used different fitness currencies. For example, females may have benefited from tolerating males through the maintenance of social niches that support breeding opportunities. Our work contributes evidence of adaptive social strategies in a solitary carnivore and support for the applicability of theories of social behavior across taxa, including solitary species in which they are rarely tested.

Preventative Disease Management and Grower Decision Making: A Case Study of California Wine-Grape Growers.

Preventative disease management is challenging to farmers because it requires paying immediate costs in the hopes of returning uncertain future benefits. Understanding farmer decision making about prevention has the potential to reduce disease incidence and minimize the need for more costly postinfection practices. For example, the grapevine trunk-disease complex (esca, Botryosphaeria dieback, Eutypa dieback, and Phomopsis dieback) significantly affects vineyard productivity and longevity. Given the chronic nature of the infections and inability to eradicate the fungal pathogens, the preventative practices of delayed pruning, applications of pruning-wound protectants, and double pruning (also known as prepruning) are the most effective means of management. We surveyed wine-grape growers in six regions of California on their use of these three practices. In spite of acknowledging the yield impacts of trunk diseases, a substantial number of respondents either choose not to use preventative practices or incorrectly adopted them in mature vineyards, too late in the disease cycle to be effective. Growers with more negative perceptions of cost efficacy were less likely to adopt preventative practices or were more likely to time adoption incorrectly in mature vineyards. In general, preventative management may require strong intervention in the form of policy or extension to motivate behavioral change.

The Role of Pest Control Advisers in Preventative Management of Grapevine Trunk Diseases.

Vineyards with trunk diseases (Botryosphaeria dieback, Esca, Eutypa dieback, and Phomopsis dieback) can have negative returns in the long run. Minimizing economic impacts depends on effective management, but adopting a preventative practice after infection occurs may not improve yields. Pest control advisers may reduce grower uncertainty about the efficacy of and need for prevention, which often entails future and unobservable benefits. Here, we surveyed advisers in California to examine their influence over grower decision-making, in the context of trunk diseases, which significantly limit grape production and for which curative practices are unavailable. Our online survey revealed adviser awareness of high disease incidence, and reduced yields and vineyard lifespan. Advisers rated both preventative and postinfection practices positively. Despite higher cost estimates given to postinfection practices, advisers did not recommend preventative practices at higher rates. High recommendation rates were instead correlated with high disease incidence for both preventative and postinfection practices. Recommendation rates declined with increasing cost for preventative, but not for postinfection, practices. Our findings suggest that even when advisers acknowledge the risks of trunk diseases, they may not recommend preventative practices before infection occurs. This underscores the importance of clear outreach, emphasizing both the need for prevention and its long-term cost efficacy.

Linking knowledge and action through mental models of sustainable agriculture.

Linking knowledge to action requires understanding how decision-makers conceptualize sustainability. This paper empirically analyzes farmer "mental models" of sustainability from three winegrape-growing regions of California where local extension programs have focused on sustainable agriculture. The mental models are represented as networks where sustainability concepts are nodes, and links are established when a farmer mentions two concepts in their stated definition of sustainability. The results suggest that winegrape grower mental models of sustainability are hierarchically structured, relatively similar across regions, and strongly linked to participation in extension programs and adoption of sustainable farm practices. We discuss the implications of our findings for the debate over the meaning of sustainability, and the role of local extension programs in managing knowledge systems.

Institutions and cooperation in an ecology of games.

Social dilemmas have long been studied formally as cooperation games that pit individual gains against those of the group. In the real world, individuals face an ecology of games where they play many such games simultaneously, often with overlapping co-players. Here, we study an agent-based model of an ecology of public goods games and compare the effectiveness of two institutional mechanisms for promoting cooperation: a simple institution of limited group size (capacity constraints) and a reputational institution based on observed behavior. Reputation is shown to allow much higher relative payoffs for cooperators than do capacity constraints, but only if (1) the rate of reputational information flow is fast enough relative to the rate of social mobility, and (2) cooperators are relatively common in the population. When these conditions are not met, capacity constraints are more effective at protecting the interests of cooperators. Because of the simplicity of the limited-group-size rule, capacity constraints can also generate social organization, which promotes cooperation much more quickly than can reputation. Our results are discussed in terms of both normative prescriptions and evolutionary theory regarding institutions that regulate cooperation. More broadly, the ecology-of-games approach developed here provides an adaptable modeling framework for studying a wide variety of problems in the social sciences.

Cooperation due to cultural norms, not individual reputation.

Increased cooperation in groups that are allowed to communicate (engage in "cheap talk") has been attributed to reputation-building and to cultural norms or culturally normal behavior. We tested these two theories by exposing groups of undergraduates to a public-goods social dilemma. Five groups were permitted to communicate via anonymous written messages that were read aloud. The groups with messaging contributed substantially more to the common good than the groups without messaging. Because the messages were anonymous, their efficacy cannot be explained by effects on reputation. Instead, the results point to the participants' histories of giving and receiving exhortations to cooperate - i.e., to culturally normal behavior (cultural norms).

Global and local concerns: what attitudes and beliefs motivate farmers to mitigate and adapt to climate change?

In response to agriculture's vulnerability and contribution to climate change, many governments are developing initiatives that promote the adoption of mitigation and adaptation practices among farmers. Since most climate policies affecting agriculture rely on voluntary efforts by individual farmers, success requires a sound understanding of the factors that motivate farmers to change practices. Recent evidence suggests that past experience with the effects of climate change and the psychological distance associated with people's concern for global and local impacts can influence environmental behavior. Here we surveyed farmers in a representative rural county in California's Central Valley to examine how their intention to adopt mitigation and adaptation practices is influenced by previous climate experiences and their global and local concerns about climate change. Perceived changes in water availability had significant effects on farmers' intention to adopt mitigation and adaptation strategies, which were mediated through global and local concerns respectively. This suggests that mitigation is largely motivated by psychologically distant concerns and beliefs about climate change, while adaptation is driven by psychologically proximate concerns for local impacts. This match between attitudes and behaviors according to the psychological distance at which they are cognitively construed indicates that policy and outreach initiatives may benefit by framing climate impacts and behavioral goals concordantly; either in a global context for mitigation or a local context for adaptation.

An institutional mechanism for assortment in an ecology of games.

Recent research has revived Long's "ecology of games" model to analyze how social actors cooperate in the context of multiple political and social games. However, there is still a paucity of theoretical work that considers the mechanisms by which large-scale cooperation can be promoted in a dynamic institutional landscape, in which actors can join new games and leave old ones. This paper develops an agent-based model of an ecology of games where agents participate in multiple public goods games. In addition to contribution decisions, the agents can leave and join different games, and these processes are de-coupled. We show that the payoff for cooperation is greater than for defection when limits to the number of actors per game ("capacity constraints") structure the population in ways that allow cooperators to cluster, independent of any complex individual-level mechanisms such as reputation or punishment. Our model suggests that capacity constraints are one effective mechanism for producing positive assortment and increasing cooperation in an ecology of games. The results suggest an important trade-off between the inclusiveness of policy processes and cooperation: Fully inclusive policy processes reduce the chances of cooperation.

Contaminated fish consumption in California's Central Valley Delta.

Extensive mercury contamination and angler selection of the most contaminated fish species coincide in California's Central Valley. This has led to a policy conundrum: how to balance the economic and cultural impact of advising subsistence anglers to eat less fish with the economic cost of reducing the mercury concentrations in fish? State agencies with regulatory and other jurisdictional authority lack sufficient data and have no consistent approach to this problem. The present study focused on a critical and contentious region in California's Central Valley (the Sacramento-San Joaquin Rivers Delta) where mercury concentrations in fish and subsistence fishing rates are both high. Anglers and community members were surveyed for their fish preferences, rates of consumption, the ways that they receive health information, and basic demographic information. The rates of fish consumption for certain ethnicities were higher than the rates used by state agencies for planning pollution remediation. A broad range of ethnic groups were involved in catching and eating fish. The majority of anglers reported catching fish in order to feed to their families, including children and women of child-bearing age. There were varied preferences for receiving health information and no correlation between knowledge of fish contamination and rates of consumption. Calculated rates of mercury intake by subsistence anglers were well above the EPA reference dose. The findings here support a comprehensive policy strategy of involvement of the diverse communities in decision-making about education and clean-up and an official recognition of subsistence fishers in the region.

Beyond existence and aiming outside the laboratory: estimating frequency-dependent and pay-off-biased social learning strategies.

The existence of social learning has been confirmed in diverse taxa, from apes to guppies. In order to advance our understanding of the consequences of social transmission and evolution of behaviour, however, we require statistical tools that can distinguish among diverse social learning strategies. In this paper, we advance two main ideas. First, social learning is diverse, in the sense that individuals can take advantage of different kinds of information and combine them in different ways. Examining learning strategies for different information conditions illuminates the more detailed design of social learning. We construct and analyse an evolutionary model of diverse social learning heuristics, in order to generate predictions and illustrate the impact of design differences on an organism's fitness. Second, in order to eventually escape the laboratory and apply social learning models to natural behaviour, we require statistical methods that do not depend upon tight experimental control. Therefore, we examine strategic social learning in an experimental setting in which the social information itself is endogenous to the experimental group, as it is in natural settings. We develop statistical models for distinguishing among different strategic uses of social information. The experimental data strongly suggest that most participants employ a hierarchical strategy that uses both average observed pay-offs of options as well as frequency information, the same model predicted by our evolutionary analysis to dominate a wide range of conditions.

Resolving conflict and building cooperation in the National Estuary program.

Since its beginning in 1987, researchers and policymakers have touted the US Environmental Protection Agency National Estuary program (NEP) as one of the leading examples of collaborative institutions designed to resolve conflict and build cooperation at the watershed level. Using the NEP as an example, I summarize the advantages and disadvantages of collaborative institutions. Using data gathered from focused surveys of policy elites in 22 estuaries, I estimate statistical models that show the NEP does a better job of resolving conflict and building project-level cooperation than similar estuaries without the NEP. I also describe the activities of the NEP mentioned by respondents as contributing to this outcome.