Georgina G. Gurney

A multi-scale biophysical model to inform regional management of coral reefs in the western Philippines and South China Sea

The health and functioning of coral reef ecosystems worldwide is in decline, and in the face of increasing anthropogenic stress, the rate of decline of these important ecosystems is set to accelerate. Mitigation strategies at regional scales are costly, but nevertheless critical, as reef systems are highly connected across regions by ocean transport of both larval propagules and pollutants. It is essential that these strategies are informed by sound science, but the inherent complexity of coral reef systems confers significant challenges for scientists and managers. Models are useful tools for dealing with complexity and can inform decision making for coral reef management. We develop a spatially explicit biophysical model for a general coral reef system. The model couples dynamics from local (10^2 m) to regional (10^6 m) scales, and explicitly incorporates larval connectivity patterns derived from sophisticated larval dispersal models. Here, we instantiate and validate the model for coral reefs in the Philippines region of the South China Sea. We demonstrate how the model can be used in decision support for coral reef management by presenting two examples of regional-scale scenario projection relating to key management issues in the Philippines: (i) marine reserve design and the recovery of fish stocks; and (ii) synergistic effects between coral bleaching and poor water quality. These scenarios highlight the importance of considering multiple stressors to reef health and patterns of larval connectivity in regional-scale management decisions.

Modelling Coral Reef Futures to Inform Management: Can Reducing Local-Scale Stressors Conserve Reefs under Climate Change?

Climate change has emerged as a principal threat to coral reefs, and is expected to exacerbate coral reef degradation caused by more localised stressors. Management of local stressors is widely advocated to bolster coral reef resilience, but the extent to which management of local stressors might affect future trajectories of reef state remains unclear. This is in part because of limited understanding of the cumulative impact of multiple stressors. Models are ideal tools to aid understanding of future reef state under alternative management and climatic scenarios, but to date few have been sufficiently developed to be useful as decision support tools for local management of coral reefs subject to multiple stressors. We used a simulation model of coral reefs to investigate the extent to which the management of local stressors (namely poor water quality and fishing) might influence future reef state under varying climatic scenarios relating to coral bleaching. We parameterised the model for Bolinao, the Philippines, and explored how simulation modelling can be used to provide decision support for local management. We found that management of water quality, and to a lesser extent fishing, can have a significant impact on future reef state, including coral recovery following bleaching-induced mortality. The stressors we examined interacted antagonistically to affect reef state, highlighting the importance of considering the combined impact of multiple stressors rather than considering them individually. Further, by providing explicit guidance for management of Bolinaos reef system, such as which course of management action will most likely to be effective over what time scales and at which sites, we demonstrated the utility of simulation models for supporting management. Aside from providing explicit guidance for management of Bolinaos reef system, our study offers insights which could inform reef management more broadly, as well as general understanding of reef systems.

Integrated conservation and development: evaluating a community-based marine protected area project for equality of socioeconomic impacts.

Despite the prevalence of protected areas, evidence of their impacts on people is weak and remains hotly contested in conservation policy. A key question in this debate is whether socioeconomic impacts vary according to social subgroup. Given that social inequity can create conflict and impede poverty reduction, understanding how protected areas differentially affect people is critical to designing them to achieve social and biological goals. Understanding heterogeneous responses to protected areas can improve targeting of management activities and help elucidate the pathways through which impacts of protected areas occur. Here, we assessed whether the socioeconomic impacts of marine protected areas (MPAs)—designed to achieve goals for both conservation and poverty alleviation—differed according to age, gender or religion in associated villages in North Sulawesi, Indonesia. Using data from pre-, mid- and post-implementation of the MPAs for control and project villages, we found little empirical evidence that impacts on five key socioeconomic indicators related to poverty differed according to social subgroup. We found suggestive empirical evidence that the effect of the MPAs on environmental knowledge differed by age and religion; over the medium and long terms, younger people and Muslims showed greater improvements compared with older people and Christians, respectively.

Efficient and equitable design of marine protected areas in Fiji through inclusion of stakeholder‐specific objectives in conservation planning

The efficacy of protected areas varies, partly because socioeconomic factors are not sufficiently considered in planning and management. Although integrating socioeconomic factors into systematic conservation planning is increasingly advocated, research is needed to progress from recognition of these factors to incorporating them effectively in spatial prioritization of protected areas. We evaluated 2 key aspects of incorporating socioeconomic factors into spatial prioritization: treatment of socioeconomic factors as costs or objectives and treatment of stakeholders as a single group or multiple groups. Using as a case study the design of a system of no-take marine protected areas (MPAs) in Kubulau, Fiji, we assessed how these aspects affected the configuration of no-take MPAs in terms of trade-offs between biodiversity objectives, fisheries objectives, and equity in catch losses among fisher stakeholder groups. The achievement of fisheries objectives and equity tended to trade-off concavely with increasing biodiversity objectives, indicating that it is possible to achieve low to mid-range biodiversity objectives with relatively small losses to fisheries and equity. Importantly, the extent of trade-offs depended on the method used to incorporate socioeconomic data and was least severe when objectives were set for each fisher stakeholder group explicitly. We found that using different methods to incorporate socioeconomic factors that require similar data and expertise can result in plans with very different impacts on local stakeholders.

Practical recommendations to help students bridge the research-implementation gap and promote conservation.

Seasoned conservation researchers often struggle to bridge the research-implementation gap and promote the translation of their work into meaningful conservation actions. Graduate students face the same problems and must contend with obstacles such as limited opportunities for relevant interdisciplinary training and a lack of institutional support for application of research results. However, students also have a crucial set of opportunities (e.g., access to academic resources outside their degree programs and opportunities to design research projects promoting collaboration with stakeholders) at their disposal to address these problems. On the basis of results of breakout discussions at a symposium on the human dimensions of the ocean, a review of the literature, and our own experiences, we devised recommendations on how graduate students can create resources within their academic institutions, institutionalize resources, and engage with stakeholders to promote real-world conservation outcomes. Within their academic institutions, graduate students should foster links to practitioners and promote knowledge and skill sharing among students. To institutionalize resources, students should cultivate student leaders and faculty sponsors, systematically document their program activities, and engage in strategic planning to promote the sustainability of their efforts. While conducting research, students should create connections to and engage actively with stakeholders in their relevant study areas and disseminate research results both to stakeholders and the broader public. Our recommendations can serve as a template for graduate students wishing to bridge the research-implementation gap, both during their current studies and in their future careers as conservation researchers and practitioners.

Designing connected marine reserves in the face of global warming

Marine reserves are widely used to protect species important for conservation and fisheries and to help maintain ecological processes that sustain their populations, including recruitment and dispersal. Achieving these goals requires well-connected networks of marine reserves that maximize larval connectivity, thus allowing exchanges between populations and recolonization after local disturbances. However, global warming can disrupt connectivity by shortening potential dispersal pathways through changes in larval physiology. These changes can compromise the performance of marine reserve networks, thus requiring adjusting their design to account for ocean warming. To date, empirical approaches to marine prioritization have not considered larval connectivity as affected by global warming. Here, we develop a framework for designing marine reserve networks that integrates graph theory and changes in larval connectivity due to potential reductions in planktonic larval duration (PLD) associated with ocean warming, given current socioeconomic constraints. Using the Gulf of California as case study, we assess the benefits and costs of adjusting networks to account for connectivity, with and without ocean warming. We compare reserve networks designed to achieve representation of species and ecosystems with networks designed to also maximize connectivity under current and future ocean-warming scenarios. Our results indicate that current larval connectivity could be reduced significantly under ocean warming because of shortened PLDs. Given the potential changes in connectivity, we show that our graph-theoretical approach based on centrality (eigenvector and distance-weighted fragmentation) of habitat patches can help design better-connected marine reserve networks for the future with equivalent costs. We found that maintaining dispersal connectivity incidentally through representation-only reserve design is unlikely, particularly in regions with strong asymmetric patterns of dispersal connectivity. Our results support previous studies suggesting that, given potential reductions in PLD due to ocean warming, future marine reserve networks would require more and/or larger reserves in closer proximity to maintain larval connectivity.

Redefining community based on place attachment in a connected world

Significance Effective environmental policy requires public participation in management, typically achieved through engaging community defined by residential location or resource use. However, current social and environmental change, particularly increasing connectedness, demands new approaches to community. We draw on place attachment theory to redefine community in the context of Australia’s Great Barrier Reef. Using a large dataset on place attachment, our analysis of local, national, and international stakeholders identified four communities differing in their attachment to the reef and spanning location and use communities. Our results suggest that place attachment can bridge geographic and social boundaries, and communities of attachment could thus be leveraged to foster transnational stewardship, which is crucial to addressing modern sustainability challenges in our globalized world. The concept of community is often used in environmental policy to foster environmental stewardship and public participation, crucial prerequisites of effective management. However, prevailing conceptualizations of community based on residential location or resource use are limited with respect to their utility as surrogates for communities of shared environment-related interests, and because of the localist perspective they entail. Thus, addressing contemporary sustainability challenges, which tend to involve transnational social and environmental interactions, urgently requires additional approaches to conceptualizing community that are compatible with current globalization. We propose a framing for redefining community based on place attachment (i.e., the bonds people form with places) in the context of Australia’s Great Barrier Reef, a World Heritage Area threatened by drivers requiring management and political action at scales beyond the local. Using data on place attachment from 5,403 respondents residing locally, nationally, and internationally, we identified four communities that each shared a type of attachment to the reef and that spanned conventional location and use communities. We suggest that as human–environment interactions change with increasing mobility (both corporeal and that mediated by communication and information technology), new types of people–place relations that transcend geographic and social boundaries and do not require ongoing direct experience to form are emerging. We propose that adopting a place attachment framing to community provides a means to capture the neglected nonmaterial bonds people form with the environment, and could be leveraged to foster transnational environmental stewardship, critical to advancing global sustainability in our increasingly connected world.

Gravity of human impacts mediates coral reef conservation gains

Significance Marine reserves that prohibit fishing are a critical tool for sustaining coral reef ecosystems, yet it remains unclear how human impacts in surrounding areas affect the capacity of marine reserves to deliver key conservation benefits. Our global study found that only marine reserves in areas of low human impact consistently sustained top predators. Fish biomass inside marine reserves declined along a gradient of human impacts in surrounding areas; however, reserves located where human impacts are moderate had the greatest difference in fish biomass compared with openly fished areas. Reserves in low human-impact areas are required for sustaining ecological functions like high-order predation, but reserves in high-impact areas can provide substantial conservation gains in fish biomass. Coral reefs provide ecosystem goods and services for millions of people in the tropics, but reef conditions are declining worldwide. Effective solutions to the crisis facing coral reefs depend in part on understanding the context under which different types of conservation benefits can be maximized. Our global analysis of nearly 1,800 tropical reefs reveals how the intensity of human impacts in the surrounding seascape, measured as a function of human population size and accessibility to reefs (“gravity”), diminishes the effectiveness of marine reserves at sustaining reef fish biomass and the presence of top predators, even where compliance with reserve rules is high. Critically, fish biomass in high-compliance marine reserves located where human impacts were intensive tended to be less than a quarter that of reserves where human impacts were low. Similarly, the probability of encountering top predators on reefs with high human impacts was close to zero, even in high-compliance marine reserves. However, we find that the relative difference between openly fished sites and reserves (what we refer to as conservation gains) are highest for fish biomass (excluding predators) where human impacts are moderate and for top predators where human impacts are low. Our results illustrate critical ecological trade-offs in meeting key conservation objectives: reserves placed where there are moderate-to-high human impacts can provide substantial conservation gains for fish biomass, yet they are unlikely to support key ecosystem functions like higher-order predation, which is more prevalent in reserve locations with low human impacts.

Local management actions can increase coral resilience to thermally-induced bleaching

Recent large-scale analyses suggest that local management actions may not protect coral reefs from climate change, yet most local threat-reduction strategies have not been tested experimentally. We show that removing coral predators is a common local action used by managers across the world, and that removing the corallivorous snail Coralliophila abbreviata from Caribbean brain corals (Pseudodiploria and Diploria species) before a major warming event increased coral resilience by reducing bleaching severity (resistance) and post-bleaching tissue mortality (recovery). Our results highlight the need for increased evaluation and identification of local interventions that improve coral reef resilience.Experimental removal of corallivorous snails from corals in the Caribbean Sea shows that this local management action can improve coral resilience to severe warming through reducing bleaching severity and post-bleaching tissue mortality.

Implementation strategies for systematic conservation planning

The field of systematic conservation planning has grown substantially, with hundreds of publications in the peer-reviewed literature and numerous applications to regional conservation planning globally. However, the extent to which systematic conservation plans have influenced management is unclear. This paper analyses factors that facilitate the transition from assessment to implementation in conservation planning, in order to help integrate assessment and implementation into a seamless process. We propose a framework for designing implementation strategies, taking into account three critical planning aspects: processes, inputs, and context. Our review identified sixteen processes, which we broadly grouped into four themes and eight inputs. We illustrate how the framework can be used to inform context-dependent implementation strategies, using the process of ‘engagement’ as an example. The example application includes both lessons learned from successfully implemented plans across the engagement spectrum, and highlights key barriers that can hinder attempts to bridge the assessment-implementation gap.