Advancing conservation planning for persistence: design of a conservation strategy for Brazilian coral reefs

Multiple stressors threaten coral reefs globally, causing severe declines of biodiversity and detrimental changes in the provision of associated ecosystem services. To counteract the ongoing biodiversity loss, systematic conservation planning provides a powerful framework to foster conservation and optimise allocation of conservation resources. However, conservation planning in the marine realm has focused mostly on representation of static elements of biodiversity within a system of marine protected areas (MPAs). The general failure of conservation planning to directly address persistence might impair the effectiveness of conservation plans. To ensure the efficacy of MPAs for future benefit, conservation planning must be capable of addressing ecological processes amenable to spatial management and mitigating threats to the long-term maintenance of biodiversity.\ud \ud The overarching objective of my thesis is to enhance the procedures by which conservation features related to processes - those both promoting and threatening the persistence of biodiversity - can be incorporated into MPA design. To enhance this integration, I focus on two influences on biological persistence, which are particularly important for fostering coral-reef conservation, but not yet well developed and interpreted in terms of conservation planning: connectivity and climate warming. By using Brazilian coral reefs as a case study, I developed methodological approaches to MPA network design that improve upon previous approaches to marine conservation for persistence in several ways: (i) by demonstrating how to formulate conservation objectives to specifically address connectivity and climate warming (Chapters 2-5); (ii) by interpreting and combining modelling tools with MPA network design that help make conservation planning more effective in addressing processes (Chapters 4 and 5); and (iii) by showing the value of setting these conservation objectives from the outset of planning (Chapter 6).\ud \ud I first quantified the spatial extent of Brazilian MPAs to protect coral reefs and investigated their spatial and geographic attributes (Chapter 2). Based on the bias in the distribution of MPAs, my study highlights that a systematic expansion of MPAs in Brazil is urgently needed to move toward an ecologically representative and functioning MPA system. Because I interpreted principles of connectivity and climate warming through generic design criteria, I next investigated more specific and tailored recommendations to formulate better conservation requirements for persistence (Chapter 3). By reviewing the conservation literature, I outlined a framework for setting marine conservation planning objectives. The framework describes six key approaches to more effectively integrating connectivity and climate warming into conservation plans, aligning opportunities and minimizing trade-offs between both goals.\ud \ud Building on this framework, I then developed methodological approaches that could be taken by planners to inform more effective planning with respect to connectivity and climate warming. In Chapter 4, I showed how functional demographic connectivity for four reef-associated species with varying dispersal abilities and a suite of connectivity metrics weighted by habitat quality can be used to set conservation objectives and inform MPA placement. Similarly, I developed an MPA design approach in Chapter 5 that includes spatially- and temporally-varying sea-surface temperature data, integrating both observed and projected time-series, to derive quantitative objectives for thermal-stress regimes.\ud \ud In Chapter 6, I re-examined the performance of Brazilian MPAs to achieve a well-balanced set of conservation objectives, explored interactions between different sets of objectives, and evaluated the consequences of pursuing single sets objectives separately in marine planning. Despite large spatial extent of MPAs protecting Brazilian coral reefs, I found the existing MPAs are placed in sub-optimal locations, unable to accumulate larvae, to function as migratory pathways, and to promote resilience to warming disturbances.\ud \ud Overall, my thesis demonstrates that stronger methodological frameworks can operationalize marine conservation planning for ecological connectivity and climate warming, resulting in improved conservation outcomes in the sea. The key requirement for this incorporation is to formulate quantitative conservation objectives underpinned by ecologically-informed parameters in the initial stages of planning