Conservation Of Marine Ecosystems Research Articles

Biomonitoring of Benthic Organisms for Coastal Protection: A Checklist Study from Pantai Remis and Blue Lagoon on the West Coast of Peninsular Malaysia

The objective of the study was to provide an updated checklist of benthic marine organisms in Pantai Remis (Selangor) and Blue Lagoon (Negeri Sembilan) in November 2022. The research areas comprised a total of 26 species of marine benthic organisms, which were divided into 12 orders, 18 families, and 22 genera. Benthic macrophytes formed the largest group (11 species), followed by other benthic macrofauna (molluscs, with eight species). In addition, three coral species, two gastropods, and two crabs were also recorded. The findings revealed that both sites are fertile and suitable habitats for marine benthic organisms. The established checklist of benthic organisms can serve as an ongoing basis for future reference as part of our efforts to develop coastal marine ecosystem management and conservation on the west coast of Peninsular Malaysia. In summary, the checklist of benthic organisms provides the basic information that is much needed for the protection of coastal ecosystems.

Integrating indigenous environmental and scientific knowledge for ecosystem-based adaptation of Muro Practices on Lembata Island

Previous studies argued that indigenous environmental knowledge was only part of local wisdom and tended to pay attention to the threat of its extinction. Indigenous environmental knowledge has not yet received recognition as an alternative perspective in dealing with the complexities of environmental management and climate change, along with the dominance of the western paradigm and current knowledge systems. This study aims to assemble the indigenous environmental knowledge systems of fisheries from communities along the coast of Lembata Island to assist in the conservation of marine ecosystems. Desk studies were used for information gathering, and the results were analyzed within the Ecosystem-based Adaptation (EbA) framework. Our results indicate that local communities in Lembata island have Muro as a temporary closure measure to manage coastal resources initiated by indigenous people that are valuable for the local people and simultaneously benefit the coastal ecosystem, including biodiversity. The results have implications for considering indigenous environmental knowledge to maintain the balance and continuity of coastal ecosystems and the main foundation in natural resource management.

Lagrangian Characterization of Surface Transport From the Equatorial Atlantic to the Caribbean Sea Using Climatological Lagrangian Coherent Structures and Self‐Organizing Maps

AbstractThis study presents an assessment of the transport of suspended material by surface ocean currents, which have a critical role in determining the connectivity and distribution of living and non‐living material. Lagrangian experiments reveal pathways from the Equatorial Atlantic to 10 strategic regions within the Caribbean Sea, determined by considering the space‐time variability of climatological Lagrangian Coherent Structures, which act as recurrent attracting pathways and transport barriers. Due to windage or Stokes drift, wind forcing is a significant factor in determining the spatial locations where particles cluster and the time needed to reach the Caribbean from the Equatorial Atlantic. Pathways shift westward within the Caribbean and take less time to arrive with increasing wind influence. Depending on the wind effect, the particles show higher confluence in different areas of the Caribbean. A case study is presented for the Mexican Caribbean nearshore area, isolated from ocean‐current trajectories. Here, wind weakens the transport barrier responsible for this isolation and causes particle confluence toward that region. Spatial patterns of the Eulerian velocity identified through Self‐Organizing Maps, with time dependence given by their best matching units, can reproduce the characteristic Lagrangian patterns of surface current climate variability. Our study demonstrates the application of tools from dynamical systems and unsupervised neural networks to understand Lagrangian patterns and identify the processes that drive them. These findings improve our understanding of transport mechanisms of suspended material by surface ocean currents in the Western Atlantic and the Caribbean Sea, which is essential for managing and conserving marine ecosystems.

A Preliminary Checklist of Molluscs in the Kelanang Coast at Banting: An Observational Study

This research aims to determine the updated species list of molluscs (Gastropods and Bivalves) populating the Kelanang coast at Banting (Selangor) in November 2022. Nine gastropod species and eight bivalve species were discovered in this study, with Pisania striata, Cominella quoyana, and Mereterix casta as the dominant species. This preliminary investigation could provide a continuous baseline for future taxonomical and biodiversity references as part of our efforts to develop coastal marine ecosystem management and conservation in the Banting coastal area. Further ecotoxicological studies to establish the potential biomonitors as good heavy metal pollution in the coastal waters of Banting are highly recommended.

The IUCN Global Standard for Nature-based Solutions™ as a tool for enhancing the sustainable development of marine aquaculture

This paper applies the IUCN Global Standard for Nature based Solutions™ self-assessment tool (published in 2020) to two aquaculture case studies. Data from the case studies were compiled by the authors. In Zanzibar, secondary data were obtained through a previous project, which included a stakeholder workshop in Zanzibar (in 2019) and one deliverable published by the IUCN on Zanzibar of their catalogue “Aquaculture and Marine Conservation”. In Indonesia, the original data were provided by the Blue Natural Capital Funding Facility (BNCFF) and the associated local teams. The analysis of the data, the information provided, and the scoring itself were done by the authors, in association with local teams in both areas. The results of the two assessments, discussed in the paper and presented in detail in the Supplementary materials, can be considered original research, never previously published in a scientific journal. The concept of Nature-based Solutions (NbS) was proposed by the International Union for Conservation of Nature (IUCN) to protect, restore, and sustainably manage natural and modified ecosystems for achieving a variety of societal benefits. The IUCN released the IUCN Global Standard for NbS™ to help design, assess, strengthen, and upscale NbS interventions. In the current context of growing uncertainties for the future of coastlines and oceans, aquaculture has been recognized as a positive activity for achieving sustainable development in coastal communities; supporting food security, poverty alleviation, and economic resilience; and contributing to the conservation of marine ecosystems in some cases. However, the sustainability of aquaculture systems has often been criticized. Aquaculture initiatives in coastal areas can achieve both nature conservation and sustainable development objectives, but reflection on the conditions under which this would happen is needed. This article examines aquaculture systems through the lens of the NbS concept and the IUCN Global Standard for NbS™, along with other sustainability concepts and instruments currently used in the context of aquaculture. The application of the IUCN Global Standard for NbS™’s to two case studies is explored: seaweed farming in Zanzibar in marine conservation areas and shrimp farming coupled with mangrove restoration in Indonesia. The results show that the NbS concept underpinning the IUCN Global Standard for NbS™ could help in the overall assessment of aquaculture systems and improve their sustainability by highlighting both their positive outcomes and issues requiring further examination in relation to marine biodiversity benefits, socio-economic development, and/or governance. The IUCN Global Standard for NbS™ could provide an operational framework to implement existing concepts, such as the Ecosystem Approach to Aquaculture, contribute to clarifying critical issues in aquaculture development, and provide guidance for the development of a new type of aquaculture project, specifically designed as NbS. This finding advocates the context-dependent exploration and promotion of aquaculture projects as NbS.

Increasing global oceanic wind speed partly counteracted water clarity management effectiveness: A case study of Hainan Island coastal waters

A sustainable coastal “blue economy” is one of the most significant opportunities and challenges in the new era. However, the management and conservation of marine ecosystems must recognize the interdependence in the coupled human and natural systems. In this study, we employed satellite remote sensing to map the spatial and temporal distribution of Secchi disk depth (SDD) in Hainan coastal waters, China for the first time, and quantitatively revealed the impacts of environmental investments on the coastal water environment in the context of global climate change. Based on the moderate resolution imaging spectroradiometer (MODIS) in situ concurrent matchups (N = 123), a simple green band (555 nm)-based quadratic algorithm was first developed to estimate the SDD for the coastal waters of Hainan Island in China (R2 = 0.70, root mean square error (RMSE) = 1.74 m). The long time-series SDD dataset (2001–2021) for Hainan coastal waters was reconstructed from MODIS observations. Spatially, SDD showed a pattern of high water clarity in eastern and southern coastal waters and low water clarity in the western and northern coastal areas. This pattern is attributed to unbalanced distributions of bathymetry and pollution from seagoing rivers. Seasonally, the humid tropical monsoon climate drove the SDD into a general pattern of high in the wet season and low in the dry season. Annually, the SDD in Hainan coastal waters improved significantly (p < 0.1), benefiting from environmental investments over the last 20 years. However, the increasing global oceanic wind speed in recent years has exacerbated sediment resuspension and deep ocean mixing, counteracting approximately 14.14% of the remedial management's effectiveness in protecting and restoring the coastal ecosystem. This study offers ways to improve the ecological and environmental regulations under global changes and to strengthen the public service capacity for aquatic management authorities with methods that support the sustainable development of coastal areas.

Pursuing sustainability? Ecosystem considerations in Japan’s fisheries governance

In pursuit of sustainable fisheries governance, global agreements have developed an ecosystem approach that requires countries to consider not only target fish stocks but also non-target species and their habitats, and to assess and mitigate the impacts of fisheries on the marine ecosystem as a whole. This study explores to what extent Japan, a major fisheries-dependent country, has incorporated such ecosystem considerations into its domestic fisheries laws and policies. Furthermore, this work examines attributes of ecosystem considerations in Japan’s fisheries policy and their consistency with established ecosystem perspectives and guidelines embedded in multilateral institutional settings. A significant feature of Japan’s fisheries policy is that it focuses on conserving fishing grounds to enhance the productivity of resources, but less on reducing bycatch or discards of non-target species and regulating practices that negatively affect habitats, unless required by regional fisheries management organizations. Therefore, Japan has not yet established a national policy or institutional framework to address the negative impacts of fisheries on ecosystems. The scope of ecosystem consideration in Japan’s fisheries governance and its inconsistencies with international instruments demonstrate substantial challenges for Japan in achieving sustainable fisheries and conserving marine ecosystems.

Strengthening Local Community in Mangrove Ecotourism at Pangandaran, West Java Province, Indonesia

This research aims to analyze Strengthening Local Community in Mangrove Ecotourism at Pangandaran, West Java Province, Indonesia. This research period was conducted in June - November 2022 Local Community in Mangrove Ecotourism at Pangandaran, West Java Province, Indonesia. The data used in this research are primary and secondary data. This research used a case study method with direct interviews using a questionnaire with ranting to scale. The sampling method used is purposive sampling method. The number of respondents in this research were 40 respondents. Analysis tool used SWOT (Strengths, Weaknesses, Opportunities and Threat). Based on research results strengthening local community in mangrove ecotourism at Pangandaran, West Java Province, Indonesia in quadrant I, then produces a strategy of strengths – opportunities (S-O), strategy showed that strength can take advantage of existing opportunities; (1) increasing public awareness of the importance of mangrove ecosystems as habitats and producers in the food chain for fish, shrimp and mollusk species; (2) mangroves are able to withstand and slow down currents and waves; (3) the marine ecosystem will be protected so that it does not mix with the mud, this is because mangrove plants have the ability to deposit mud; (4) it has an economic function as a natural tourist attraction which attracts tourists; (5) education is needed for the surrounding community and tourists who come to visit regarding the role of mangrove ecosystems in coastal areas. Based on the results of the research can be recommended Mangrove ecotourism is seen as synergizing with the conservation of fisheries and marine resource ecosystems by applying local wisdom in the community. The development of mangrove ecotourism is an effort to utilize environmental services from coastal areas sustainable by involving local institutions that aim to have socio-economic and cultural values for the community.

Tracking integrated ecosystem assessments in the ICES network: a social network analysis of the ICES expert groups

AbstractThe advice the International Council for the Exploration of the Sea (ICES) provides to its member countries is crucial for the sustainable management of shared marine resources, and the conservation of relevant marine ecosystems. In 2014, ICES made a strategic decision to integrate marine and social sciences in a new type of assessment framework called “integrated ecosystem assessments” (IEA) to deliver advice on societal trade-offs between different policy options. The IEA-focused expert groups formed before and after this period now cover all major ecoregions. To track the progression of IEAs in the ICES network over time, we conducted a social network analysis (SNA) on expert group attendance for the years 2015–2019. The IEA-focused expert groups generally ranked lower in the overall ICES network. Our study shows that some IEA-groups become more connected over time, while others decline. We also evaluated the role of workshops in the ICES network, particularly their role in the development of IEA knowledge. Our study shows that workshops play an important role in ICES network connectivity. The study demonstrates how social network analysis can be used to study an organization such as ICES and determine the effectiveness, or impact, of that organizational function.

Stakeholder perspectives on socio-economic challenges and recommendations for better management of the Aliwal Shoal Marine Protected Area in South Africa

Marine Protected Areas (MPAs) regulate human behaviour within their boundaries to support long-term conservation of marine ecosystems and associated human benefits. As complex socio-ecological systems, the success of MPAs is fundamentally reliant upon community and stakeholder engagement, support, and compliance. Using the Aliwal Shoal MPA in South Africa as a case study, 48 stakeholder interviews were conducted to explore perceptions of existing challenges and potential solutions relating to management of the MPA. Analysis identified several challenges including: i) non-compliance with existing laws; ii) insufficient marine law enforcement; iii) national corruption; iv) poor physical infrastructure, and v) perceived racially biased MPA regulations. To address these challenges, interviewees highlighted the following potential solutions: i) development of awareness raising initiatives to foster marine stewardship and support for the MPA; ii) improving the visibility of marine conservation and MPA management activities; iii) investing finances generated by the Aliwal Shoal MPA regulations (such as diving permit fees) directly into MPA management; iv) identifying and enhancing local skills and knowledge that could contribute to enhancing conservation activities; and v) exploring innovative technical solutions that can improve community awareness and compliance with MPA regulations. While not representative of the entire spectrum of stakeholders, this paper provides useful insights that can be used by national MPA implementing agencies, local management bodies and conservation organisations as they try to improve engagement with local stakeholders to optimise social, economic, and ecological benefits, and contribute to improved governance. Additionally, the paper contributes to the global call for improved communication and engagement with stakeholders about MPAs, especially considering the increased emphasis placed on protected areas for global conservation.

Apparent survival probability and abundance of juvenile green turtles in the foraging ground at Kuroshima Island, Ryukyu Archipelago

An understanding of the survival probability and abundance of endangered species is critical for their effective conservation and management. In this study, long-term capture-mark-recapture data were used to estimate the apparent survival probability and abundance of green turtles Chelonia mydas at Kuroshima Island in the Yaeyama Islands, Japan. A total of 453 turtles were captured from 2009 to 2020 using entangling nets. All captured turtles were juveniles and subadults; no adult turtles were captured during this study. The estimated apparent survival rate of this aggregation was 0.82 (95% CI = 0.76-0.86) using the Cormack-Jolly-Seber model, which accounts for both permanent emigration and death. Annual abundance was estimated using the Horvitz-Thompson estimator. Estimated abundance increased from 234 (95% CI = 182-286) in 2009 to 418 (95% CI = 325-510) in 2020. This trend in abundance for green turtles in the foraging ground may result from the increasing nesting population in this region. Our study provides information for understanding the life cycle of green turtles in the Yaeyama Islands and for the conservation and management of marine ecosystems in this region.

Fishing for biodiversity by balanced harvesting

AbstractFisheries are damaging and seemingly incompatible with the conservation of marine ecosystems. Yet fish are an important source of food and support the lives of many people in coastal communities. This paper considers an idea that a moderate intensity of fishing, appropriately scaled across species, could help in maintaining biodiversity, rather than reducing it. The scaling comes from an intuition that rates of fishing mortality of species should be kept in line with production rates of the species, a notion known as balanced harvesting. This places species conservation and exploitation on an equal footing in a single equation, showing quantitatively the relative levels of fishing mortality that species of different abundance can support. Using a dynamic model of a marine ecosystem, we give numerical evidence showing for the first time that fishing, if scaled in this way, can protect rarer species, while allowing some exploitation of species with greater production. This works because fishing mortality rates, when scaled by production, are density‐dependent. Such fishing, operating adaptively to follow species' production rates over time, contains a feedback that would help to protect species from overfishing in the presence of uncertainty about how marine ecosystems work.

Spatial protection tools as indicators of the ‘health’ of the Antarctic Treaty system

AbstractWhat do ongoing discussions about Antarctic spatial protection tools tell us about the ‘health’ or overall condition of the Antarctic Treaty system 60 years after its entry into force? The Antarctic Treaty (1959, in force 1961) resulted from the alignment of common international interests (e.g., maintenance of peace, freedom of scientific investigation) with the national interests of original signatory states (e.g., ‘freezing’ of diverging positions on territorial claims). Later instruments adopted by Antarctic Treaty states replicated this scheme and allowed agreement on, among other issues, environmental protection, and marine ecosystem conservation. This paper draws on an examination of the series of spatial protection tools in force established by the main Antarctic Treaty system bodies, and observations conducted in annual decision‐making meetings. Issues of conflict emerge as the size, complexity, and conservation ambitions of spatial protection tools increase, resulting in a weakening of the proposals and lack of consensus. This paper argues that establishing spatial protection tools reflects an intent by Antarctic Treaty states to engage with the Antarctic Treaty system for the longer term; however, the establishment trajectory of spatial protection tools is sensitive to resource interests and broader Antarctic geopolitics. Ongoing difficulties of Antarctic Treaty fora to reach consensus on the spatial protection tools they agreed to establish – and on other important issues – bring into question the current effectiveness of the Antarctic Treaty system. The path to recovery requires Antarctic Treaty states to negotiate in good faith with a view to finding consensus, while upholding the environmental objectives of Antarctic Treaty system instruments.

Stakeholders’ perceptions on environmental quality and threats to subtropical marine reserves

Marine Protected Areas (MPAs) have been one of the main strategies for the conservation of marine ecosystems and an attempt to buffer or revert anthropogenic and natural disturbances. However, only the implementation of an MPA does not guarantee effectiveness in the maintenance of these environments. The involvement of the stakeholders in the whole process is crucial for the MPAs to achieve their conservation goals. With this, we provide here an understanding of the dynamics on how different stakeholders engage in marine reserves management, to inform courses of action and improve conservation and governance at multiple scales. Through semi-structured questionnaires, we investigated which anthropogenic threats were mostly perceived by stakeholders in three Brazilian marine reserves. We compare the perceptions of the members of the management councils and the staff of each reserve, in addition to verifying whether there were differences among their perceptions and to identify correlations between perceptions on management effectiveness and environmental quality. Illegal fishing and exotic species were the most important threats identified. No differences were verified between the perceptions of managers and members of the management board of the marine reserve and there was also no relationship between the perception of effectiveness and quality of environmental attributes. The different stakeholders’ interests and their socioeconomic and cultural background is discussed as influencing the perceptions of management effectiveness. However, the similarity in threat perceptions reported in this study may be explained by the lower level of complexity and subjectivity in opinions in comparison with management effectiveness evaluations. Our results provide an overview of perceptions on threats and on the environmental quality of subtropical marine reserves in the Southwestern Atlantic, which can be used to guide funding and policy priorities that mitigate the effects of anthropogenic threats on marine reserves and thus contribute to creating a win–win scenario.

Evaluation of the effect and investment benefit of Marine ecosystem protection and restoration

In order to explore the effectiveness of Marine ecosystem conservation and restoration, an evaluation method based on the effectiveness and investment benefit of Marine ecosystem conservation and restoration was proposed. This method recommends key technical problems and solutions based on the information represented by Marine ecosystem protection to explore the effectiveness of Marine ecosystem protection and restoration. The results show that the evaluation efficiency of Marine ecosystem protection and restoration and investment benefit is about 30% higher than that of traditional methods. Due to the uncertainty of Marine ecological restoration, the role of adaptive management in Marine ecological restoration has been paid more and more attention, and the systematic process of improved management adapted to new knowledge and information has been explored.

Artificial intelligence and automated monitoring for assisting conservation of marine ecosystems: A perspective

Conservation of marine ecosystems has been highlighted as a priority to ensure a sustainable future. Effective management requires data collection over large spatio-temporal scales, readily accessible and integrated information from monitoring, and tools to support decision-making. However, there are many roadblocks to achieving adequate and timely information on both the effectiveness, and long-term success of conservation efforts, including limited funding, inadequate sampling, and data processing bottlenecks. These factors can result in ineffective, or even detrimental, management decisions in already impacted ecosystems. An automated approach facilitated by artificial intelligence (AI) provides conservation managers with a toolkit that can help alleviate a number of these issues by reducing the monitoring bottlenecks and long-term costs of monitoring. Automating the collection, transfer, and processing of data provides managers access to greater information, thereby facilitating timely and effective management. Incorporating automation and big data availability into a decision support system with a user-friendly interface also enables effective adaptive management. We summarise the current state of artificial intelligence and automation techniques used in marine science and use examples in other disciplines to identify existing and potentially transferable methods that can enable automated monitoring and improve predictive modelling capabilities to support decision making. We also discuss emerging technologies that are likely to be useful as research in computer science and associated technologies continues to develop and become more accessible. Our perspective highlights the potential of AI and big data analytics for supporting decision-making, but also points to important knowledge gaps in multiple areas of the automation processes. These current challenges should be prioritised in conservation research to move toward implementing AI and automation in conservation management for a more informed understanding of impacted ecosystems to result in successful outcomes for conservation managers. We conclude that the current research and emphasis on automated and AI assisted tools in several scientific disciplines may mean the future of monitoring and management in marine science is facilitated and improved by the implementation of automation.

Seagrass meadows in the Greek Seas: presence, abundance and spatial distribution

Abstract Combined use of optical (satellite imagery) and acoustic (sidescan sonar) remote sensing techniques, as well as in situ methodologies (visual census; SCUBA diving, Towed Underwater Cameras, and Remotely Operated Vehicles) was employed to map the spatial distribution of seagrass habitats in the coastal waters of the Greek territory. Seagrass meadows were recorded over approximately 70% of the Greek coastline (Eastern Ionian, Aegean and Levantine Seas), and their surface area exceeded 2749.07 km2. Posidonia oceanica is clearly the dominant seagrass species in Greek Seas, covering the vast majority of seabed at depths between the shoreline and 25–30 m (or deeper in insular areas), followed by the species Cymodocea nodosa, Zostera noltei, and Halophila stipulacea, that are not widely distributed but are locally abundant in specific areas. Habitat suitability in terms of the of the seabed that is available for the growth of seagrass meadows (i.e., the spatial extent of coastal areas between the shoreline and the isobath of 20 m) and the seawater clarity conditions are highlighted as the critical factors for the formation of well-structured and extensive meadows. The results of this study are of great importance and usefulness for the effective management and conservation of valuable marine ecosystems and are given in the form of an openly accessible shapefile.

Forecasting shifts in habitat suitability of three marine predators suggests a rapid decline in inter-specific overlap under future climate change.

Understanding how environmental and climate change can alter habitat overlap of marine predators has great value for the management and conservation of marine ecosystems. Here, we estimated spatiotemporal changes in habitat suitability and inter‐specific overlap among three marine predators: Baltic gray seals (Halichoerus grypus), harbor seals (Phoca vitulina), and harbor porpoises (Phocoena phocoena) under contemporary and future conditions. Location data (>200 tagged individuals) were collected in the southwestern region of the Baltic Sea; one of the fastest‐warming semi‐enclosed seas in the world. We used the maximum entropy (MaxEnt) algorithm to estimate changes in total area size and overlap of species‐specific habitat suitability between 1997–2020 and 2091–2100. Predictor variables included environmental and climate‐sensitive oceanographic conditions in the area. Sea‐level rise, sea surface temperature, and salinity data were taken from representative concentration pathways [RCPs] scenarios 6.0 and 8.5 to forecast potential climate change effects. Model output suggested that habitat suitability of Baltic gray seals will decline over space and time, driven by changes in sea surface salinity and a loss of currently available haulout sites following sea‐level rise in the future. A similar, although weaker, effect was observed for harbor seals, while suitability of habitat for harbor porpoises was predicted to increase slightly over space and time. Inter‐specific overlap in highly suitable habitats was also predicted to increase slightly under RCP scenario 6.0 when compared to contemporary conditions, but to disappear under RCP scenario 8.5. Our study suggests that marine predators in the southwestern Baltic Sea may respond differently to future climatic conditions, leading to divergent shifts in habitat suitability that are likely to decrease inter‐specific overlap over time and space. We conclude that climate change can lead to a marked redistribution of area use by marine predators in the region, which may influence local food‐web dynamics and ecosystem functioning.

Marine Protected Areas Management in the Mediterranean Sea—The Case of Croatia

Marine protected areas (MPAs) are widely used tools to conserve marine ecosystems and their services. They are complex socio-ecological systems where human activities and nature interact. Croatia has 409 protected areas, of which 19 are coastal-marine. The aim of this paper is to analyze the management model of MPAs in Croatia and to identify their strengths and weaknesses. For this purpose, three MPAs have been chosen: Brijuni National Park, Telašćica Nature Park, and Pakleni Islands Significant Landscape. The methodology used assesses 26 specific indicators to analyze the status of 4 key factors: management body, planning subprocess, public participation, and implementation subprocess. The results of this evaluation are 5 possible scenarios: proactive (1), learning (2), interactive (3), centralized (4), and formal (5) management. The results show that Brijuni presents a proactive scenario (1), Telašćica an interactive scenario (3), and Pakleni Islands a centralized scenario (4). A series of measures are presented, which can improve the score. In general, MPA management in Croatia tends towards a proactive model, where the management body is its greatest strength. There is a shift from a top-down to a bottom-up approach, which implies a greater involvement of the population in decision-making. However, public participation is not yet fully consolidated.

Multiscale mechanical consequences of ocean acidification for cold-water corals

Ocean acidification is a threat to deep-sea corals and could lead to dramatic and rapid loss of the reef framework habitat they build. Weakening of structurally critical parts of the coral reef framework can lead to physical habitat collapse on an ecosystem scale, reducing the potential for biodiversity support. The mechanism underpinning crumbling and collapse of corals can be described via a combination of laboratory-scale experiments and mathematical and computational models. We synthesise data from electron back-scatter diffraction, micro-computed tomography, and micromechanical experiments, supplemented by molecular dynamics and continuum micromechanics simulations to predict failure of coral structures under increasing porosity and dissolution. Results reveal remarkable mechanical properties of the building material of cold-water coral skeletons of 462 MPa compressive strength and 45–67 GPa stiffness. This is 10 times stronger than concrete, twice as strong as ultrahigh performance fibre reinforced concrete, or nacre. Contrary to what would be expected, CWCs retain the strength of their skeletal building material despite a loss of its stiffness even when synthesised under future oceanic conditions. As this is on the material length-scale, it is independent of increasing porosity from exposure to corrosive water or bioerosion. Our models then illustrate how small increases in porosity lead to significantly increased risk of crumbling coral habitat. This new understanding, combined with projections of how seawater chemistry will change over the coming decades, will help support future conservation and management efforts of these vulnerable marine ecosystems by identifying which ecosystems are at risk and when they will be at risk, allowing assessment of the impact upon associated biodiversity.