Expectations about ecosystem based management (EBM) differ due to diverging perspectives about what EBM should be and how it should work. While EBM by its nature requires trade-offs to be made between ecological, economic and social sustainability criteria, the diversity of cross-sectoral perspectives, values, stakes, and the specificity of each individual situation determine the outcome of these trade-offs. The authors strive to raise awareness of the importance of interaction between three stakeholder groups (decision makers, scientists, and other actors) and argue that choosing appropriate degrees of interaction between them in a transparent way can make EBM more effective in terms of the three effectiveness criteria salience, legitimacy, and credibility. This article therefore presents an interaction triangle in which three crucial dimensions of stakeholder interactions are discussed: (A) between decision makers and scientists, who engage in framing to foster salience of scientific input to decision making, (B) between decision makers and other actors, to shape participation processes to foster legitimacy of EBM processes, and (C) between scientists and other actors, who collaborate to foster credibility of knowledge production. Due to the complexity of EBM, there is not one optimal interaction approach; rather, finding the optimal degrees of interaction for each dimension depends on the context in which EBM is implemented, i.e. the EBM objectives, the EBM initiator’s willingness for transparency and interaction, and other context-specific factors, such as resources, trust, and state of knowledge.
In 2011 humans caught and consumed 78.9 million tonnes of fish, crustaceans, molluscs and other species groups from the world’s oceans, accounting for 16.6% of the world’s animal protein intake (FAO 2012). This is projected to increase further, to over 93 million tonnes by 2030 (World Bank 2013). Global demand for fish products has increased dramatically over recent decades. Fishing is also an important livelihood, globally providing employment to 38.4 million people of whom 90% are employed in small-scale fisheries (FAO 2012). The importance of fisheries continues to rise as coastal populations are increasing, and rapidly growing economies are driving up demand for fish. While aquaculture is increasing to meet some of this demand, wild capture fisheries continue to be critically important.
This review of the scientific literature provides a deep exploration of the importance of mangroves for wild capture fisheries. While mangroves are widely recognized for their role in enhancing both small scale and commercial fisheries, they are rapidly disappearing. A fuller understanding of this ecosystem service and its value in both social and economic terms will help enhance the sustainable management of both mangroves and fisheries.
The report firstly discusses some of the ecological processes which underpin the key role of mangroves in fisheries enhancement, followed by an exploration of the different mangrove- associated fishery types. As the fisheries value of mangroves is highly site specific, the report explores the drivers and mechanisms which can help to explain for different locations how many fish a mangrove produces, how many are caught by humans, and what the fisheries value is, both in economic terms, as a food supply or through the livelihoods that they support. Decision-makers can use this information to determine where fish productivity is highest, which allows them to make adequate decisions relating to conservation and restoration actions and sustainable fishing. We conclude with management recommendations for maintaining or enhancing the value of mangroves for fisheries for the long-term.
The role of mangroves in protecting our coasts against natural hazards such as storms, tsunamis and coastal erosion has been widely promoted. But the supposed coastal protection services of mangroves have also been subject to debate. The Nature Conservancy and Wetlands International together with the University of Cambridge set out to map the current state of knowledge about the role of mangroves in coastal defence and put the different findings and views in perspective. The conclusion is that mangroves can indeed reduce the risk from a large number of hazards. This practical guidebook summarises the findings of the reviews and provides practical management recommendations to coastal zone managers and policymakers. These are the key messages:
Section 1. Is my shore at risk?
Section 2. The role of mangroves in coastal risk reduction
Section 3. Managing mangroves for coastal defence
Section 4. Recognizing the multiple values of mangroves
Despite many biotic, physical, and political challenges for place-based conservation in open ocean environments, conservation of discrete oceanic regions by designating pelagic marine protected areas (PMPAs) has gained considerable traction. In the oligotrophic central Pacific, a patchy and dynamic ecosystem, a robust network of PMPAs has recently been established. However, evaluations of PMPA efficacy in providing appropriate habitat coverage for pelagic species are lacking, particularly in the tropics. Here, we used high resolution GPS tracking and home range analyses of tropical boobies to determine the distribution and foraging habitat use of three sympatric species (Sula sula,Suladactylatra, and Sulaleucogaster) in two PMPAs that varied substantially in size and shape. At each site we characterized the extent and use of foraging habitat inside and outside the PMPA that surrounded each breeding colony. We found profound variation within and among species in foraging behavior and habitat use across the two sites; this was partially explained by variation in bathymetry. Yet, despite variation both in PMPA size and shape, and in foraging behavior of the birds, we determined that the PMPAs each encapsulated more than 85% (n = 216 trips) of foraging habitat for each species, indicating that these PMPAs provided important habitat coverage for highly mobile tropical species. While this study highlights the challenges in effectively designing PMPAs even for relatively well-studied, central place foragers, given strong variation in foraging ecologies across sites, it also suggests that PMPAs do provide meaningful habitat coverage for at least some pelagic species.
Giant clams (Hippopus and Tridacna species) are thought to play various ecological roles in coral reef ecosystems, but most of these have not previously been quantified. Using data from the literature and our own studies we elucidate the ecological functions of giant clams. We show how their tissues are food for a wide array of predators and scavengers, while their discharges of live zooxanthellae, faeces, and gametes are eaten by opportunistic feeders. The shells of giant clams provide substrate for colonization by epibionts, while commensal and ectoparasitic organisms live within their mantle cavities. Giant clams increase the topographic heterogeneity of the reef, act as reservoirs of zooxanthellae (Symbiodinium spp.), and also potentially counteract eutrophication via water filtering. Finally, dense populations of giant clams produce large quantities of calcium carbonate shell material that are eventually incorporated into the reef framework. Unfortunately, giant clams are under great pressure from overfishing and extirpations are likely to be detrimental to coral reefs. A greater understanding of the numerous contributions giant clams provide will reinforce the case for their conservation.
We argue that stakeholder commitment and cooperation is essential for the success of strategic coastal and marine management initiatives and draw upon social identity theory to explain how inter-group relationships can either support or hinder cooperation across stakeholder groups. We analyse data from interviews carried out with 24 coastal and marine stakeholders from the Northern Territory, Australia, looking at how stakeholders describe their objectives for coastal and marine management and evidence of social identity effects either facilitating or impeding cooperation between stakeholders. While most participants sought improvements to coastal and marine management, only some were thinking in terms of a more regional-scale, forward-looking and integrated approach. Strong social identity effects inhibiting cooperation between stakeholders were evident in many of the interviews. However, the interviews also revealed shared objectives (e.g., the need for more data, to avoid duplication of effort, and more transparent and systematic decision-making) that could serve as a basis for developing a common social identity, and fostering the commitment and cooperation needed for strategic coastal and marine management initiatives.
This paper illustrates an index-based coastal risk assessment that was performed on a micro-tidal alluvial plain taking into account the relative sea level rise (RSLR) for the evaluation of coastal vulnerability and exposure. This process took into account both the inundation of inshore land and the beach retreat due to storm surge, calculated on the basis of geomorphological data (bathymetry, sedimentology and beach width) and wave climate. The evaluation process was conceived with reference to a low and high hazard, associated with a wave storm with 1 year and 50 years return period. For the latter case, the response to RSLR was calculated taking into account both isostatic response and ice cap melting due to global warming, while the vertical land movement was assessed taking into account the different its rates in the northern and southern coastal area. The exposure and the damage of the coastal assets were evaluated with a simplified conceptual framework, which uses land cover data and a statistical population dataset.
The risk assessment procedure was applied to Sele coastal plain, which involves numerous properties and important infrastructures, and is strongly susceptible to marine inundations. A sensitivity analysis of the vulnerability and the risk relative to different hazards and to RSLR was performed. Moreover, the final risk assessment classification was validated with a conceptual framework based on the observed damage ranking related to the tested coastal area.
The obtained results showed that the northern high density urban areas were characterized by the highest risk, followed by some central areas with strong localized erosive focus. On the contrary, the southern zones, with wider beaches and almost intact dunes, were characterized by the lowest risk level. The results of this study were used for the development of a coastal protection project which, in fact, provided a different scheme for the coastline northwards and southwards of the Sele river mouth, according to the different risk ranking established.
Managed retreat is rarely implemented on exposed sandy coasts because of public interest in beach recreation and the great human-use value of existing beaches and dunes. The feasibility of retreat on the sandy coast of the Adriatic Sea in the Region of Emilia-Romagna was evaluated at a site with a single user facility (a beach concession) backed by public parkland. A conceptual scenario of changes to landforms and habitats was developed for the retreat option. Interviews with key stakeholders revealed perceptions of alternatives for addressing erosion and flooding by managed retreat or by protecting existing features in place.
The beach concession occupies a segment of shore between an eroding (−9.3 m yr−1) washover barrier updrift and an accreting beach downdrift. Landward of the concession is a portion of the Po Delta Park, consisting of a brackish lagoon and marsh and an artificially-created freshwater lake. Shore protection projects have maintained the concession and the integrity of a dike protecting the lake. Allowing retreat to occur would cause (1) loss of the concession in its present location; (2) erosion of the dike, converting the lake to brackish habitat; and (3) migration of the shoreline to a pine forest, campground and residences that are now 500 m from the shoreline. Freshwater and pine forest habitat would be lost, but salt water wetland and pioneer coastal species would be restored. The beach and campground could still be used as the shoreline migrates inland, but with less fixed infrastructure. Landward facilities could be protected by a ring dike.
At issue is whether normally dynamic and short-term landforms and habitats should be protected as static features in perpetuity and whether human actions should be taken to protect human-created nature (lake, pine forest) against natural evolutionary processes. Stakeholders indicated that managed retreat should occur eventually but existing features should be protected now. The retreat option is compatible with Regional ICZM plans, but differs from the standard engineering designs actually suggested for implementation. The benefits of managed retreat on exposed sandy shores can only be presented in conceptual terms until demonstration projects provide concrete answers, so it is not surprising that the undocumented benefits of a more dynamic shoreline have little appeal relative to maintaining the status quo.
Similar to many coastal or island countries, the waters around St. Kitts and Nevis, an island nation in the Eastern Caribbean, are home to multiple, cumulative, and often conflicting uses of the sea. Marine spatial planning and marine zoning hold great promises for addressing and balancing a number of marine management objectives in St. Kitts and Nevis under a common framework. We outline the key activities that led to the development of a draft marine zoning design for St. Kitts and Nevis, and discuss outcomes of the planning process and possible next steps towards implementation of a marine zoning plan. The key activities were focused around: 1) engaging stakeholders; 2) establishing clear objectives; 3) building an information base that spatially represents marine uses (i.e., a multi-objective geodatabase); 4) generating tools to assist stakeholders and decision makers in generating a zoning design and considering options and tradeoffs (i.e., decision support products); and 5) outlining the location of zones via a participatory process. The vision and foundation for marine zoning we outline here can continue to be leveraged by the citizen of St. Kitts and Nevis and serve as a model in other places engaged in similar efforts.
A significant barrier to the use of public participation GIS (PPGIS) and crowd-sourcing for conservation planning is uncertainty about the quality of the spatial data generated. This study examines the quality of PPGIS data for use in conservation planning. We evaluate two dimensions of spatial data quality, positional accuracy and data completeness using empirical PPGIS data from a statewide study of public lands in Victoria, Australia. Using an expert-derived spatial conservation model for Victoria as a benchmark, we quantify the performance of a crowd-sourced public in their capacity to accurately and comprehensively identify areas of high conservation importance in the PPGIS process. About 70% of PPGIS points that identified biological/conservation values were spatially coincident (position accurate) with modeled areas of high conservation importance, with greater accuracy associated with locations in existing protected areas. PPGIS data had less positional accuracy when participants identified biological values in urban areas and on non-public lands in general. The PPGIS process did not comprehensively identify all the largest, contiguous areas of high conservation importance in the state, missing about 20% of areas, primarily on small public land units in less densely populated regions of the state. Preferences for increased conservation/protection were over-represented in areas proximate to the Melbourne urban area and under-represented in more remote statewide locations. Our results indicate that if PPGIS data is to be integrated into spatial models for conservation planning, it is important to account for the spatial accuracy and completeness limitations identified in this study (i.e., urban areas, non-public lands, and smaller remote locations). The spatial accuracy and completeness of PPGIS data in this study suggests spatial data quality may be “good enough” to complement biological data in conservation planning but perhaps not good enough to overcome the mistrust associated with crowd-sourced knowledge. Recommendations to improve PPGIS data quality for prospective conservation planning applications are discussed.