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This thesis develops analytical frameworks for evaluating the validity of MBES data with comparable ground truthing and hydrodynamic data with respect to geomorphology and marine biodiversity in two Special Areas of Conservation (SAC) in the Malin-Hebrides Sea off the north-Irish coast. First, a modelling framework based on Generalised Linear Modelling (GLM) is developed to test the validity of multi-frequency MBES backscatter data (30, 95, 300 kHz) to characterise sediment grain size in the Hempton's Turbot Bank (HTB) SAC. The results demonstrate that the single-frequency sources have a marginal gain on the multi-frequency model, with the 30 kHz model driving the significance of the multi-frequency model, and the inclusion of the higher frequencies diminishes the level of agreement. Secondly, a combination of K-Means unsupervised classification and GLM based on MBES backscatter (95, 300 kHz) and bathymetry analysis are successfully used to predict different levels of sandeel Hyperoplus lanceolatus densities with respect to geomorphology in the HTB SAC. The study demonstrates that the lower frequency source is more adept at capturing the variety inherent in shallow sub-surface sedimentary environments, which this species prefers. Finally, multidisciplinary modelling and analysis approaches using MBES data, hydrodynamic data and theodolite tracking observations are used to assess the spatial dynamics of harbour porpoise Phocoena phocoena in the Skerries and Causeway SAC. Generalised Additive Modelling (GAM) identifies that slope, aspect and backscatter intensity are the most statistically significant variables accounting for the highest deviance in porpoise sighting density. Models predict a high probability (> 0.6) of porpoise encounters in nearshore areas, particularly concentrated around headlands where local flow acceleration results in coarser beds. The robust workflows developed in this thesis, provides a proof of concept for developing robust monitoring strategies for Marine Protected Areas and associated species. Respective recommendations will inform marine policy, marine spatial planning and management.

Although deep-sea science continues to progress, the southern hemisphere represents a vast and yet understudied area, and the South Atlantic is no exception to this. However, as with other ocean basins, blue growth and the potential for expansion of new and emerging industries mean that information is required to characterise the ecology of the basin to inform sustainable management. Furthermore, novel tools will be required to assist in translating ecological knowledge into usable products that can facilitate marine spatial planning. The aims of this thesis were to contribute to our understanding of the benthic ecology of seamount and oceanic island ecosystems in the South Atlantic, and to trial new methodologies for the development of tools to facilitate sustainable management of the deep sea. The results of this thesis show that productivity and substrate hardness are both significant drivers of α-diversity on seamount and oceanic island ecosystems, manifesting in significantly higher α-diversity in temperate latitudes. Interestingly, no consistent relationship between α-diversity and depth was identified, upon further exploration, significant bathymetric β-diversity (turnover) gradients were identified. Further developing our ecological understanding of the basin, similarities and dissimilarities in community structure across the South Atlantic were explored, again linking ecological distributions with environmental parameters. Significant differences between deep-sea communities from temperate and tropical latitudes were identified, with latitude and depth considered the key environmental drivers of community composition. Vulnerable Marine Ecosystems (VMEs) were identified in both tropical and temperate latitudes, often displaying strong similarities to faunal assemblages described in the North Atlantic. These findings suggest that South Atlantic seamounts and oceanic islands may harbour significant abundance and diversity of deep-sea species and assemblages including those protected through various legal instruments. This thesis also addresses how to appropriately inform sustainable management of data-poor ocean basins in multiple ways: the first explores the use of a model transfer approach across a data gradient from rich to poor and ascertains the ecological relevance of modelled predictions through independent validation using data from the South Atlantic. The second uses ecological variables known to drive species distributions to develop a global habitat classification. The final output is evaluated against faunal zonation literature and other modelled outputs, considering both our current understanding of drivers of global species and habitat distribution, and the drivers and distributions identified within this thesis for the South Atlantic.

Without a substantial and sustained reduction in greenhouse gas emissions, climatic change will increase the likelihood of severe, and irreversible impacts for people and ecosystems. Such change requires the acceleration of multilevel (social, political and technological) and cross-sectoral transformation towards a low-emissions world. This transition to a low carbon economy is particularly pertinent in the marine environment, comprising a range of measures (e.g. area-based conservation, and spatial planning) and activities including offshore wind deployment, habitat restoration, and technological innovation (e.g. electric ships). Facilitating the low carbon transition thus requires the resolution of highly interrelated economic, environmental, social, and cultural conflicts of interests. Spatial management of these activities, via mechanisms such as marine spatial planning (MSP) will be central to realising the transition by integrating decision-making. Advanced as an accessible and ecosystem approach to marine management, MSP has quickly become adopted as a rational governance process for addressing spatial and temporal distributions of marine activities and issues. In practice, however, MSP initiatives appear to repackage the status quo in empty participatory rhetoric providing the appearance of democratic legitimacy to neoliberal exploitation. The collaborative and contested nature of the low carbon transition compels this study to consider how leading MSP initiatives function to create cross-community understanding and coordinated action. In response, this thesis claims to make three key contributions to knowledge. The first relates to a better understanding of institutional resistance in MSP. An analysis of political texts (speeches and documents), marine plan documents, and semi-structured interviews illustrates how realisation of the low carbon transition within the UK's MSP programme was fundamentally restricted by the broader institutional context and political regime. This thesis thus challenges the notion that MSP can be re-politicised so as to facilitate a step-wise change in the governance of the marine area. The second relates to a comparative analyse of MSP in England and Scotland in which the constitutional complexity of the UK's pioneering climate and MSP legislative frameworks is foregrounded. The justification and realisation of MSP the low carbon transition is reflective of the asymmetrical distribution of legal powers to Devolved Administrations. MSP thus propagates the centralisation of decision-making and returns. Finally, the thesis makes a theoretical contribution by developing a theoretical framework - distinguishing between boundary and pseudo-boundary objects - for examining the dynamic process of multi-community cooperation where there is the expectation of obstructive collaboration. The concept of 'boundary objects' has provided a rich framework for analysing collaborative processes involving heterogeneous communities. A bias within the literature was found that sought to black-box every cross-community thing, regardless of how it functions between communities, as a boundary object. This study argues that conceptually extending boundary objects to cover situations that are both enabling and inhibitory weakens the core value of the concept. Subsequently, by focussing on the functions rather than the features of boundary objects and linking this to the way knowledge may be controlled at community boundaries, the theoretical framework introduces an alternative typology: pseudo-boundary objects that operate in situations of obstructive collaboration. The development and subsequent application of this framework helps clarify how power inequalities can corrupt the sharing of knowledge within the implementation of MSP in England and Scotland.

For half a century, the seas have been transforming from a mare nullius, to an area of enclosed and private rights. Despite the growing body of literature addressing these transitions, there has been a lack of engagement with property rights and enclosure in Scotland's seas. Using a conceptual lens of historical institutionalism, the research explores the drivers, consequences, and perceptions of enclosure in two case studies in Scotland; spatial enclosure via marine spatial planning, and resource access enclosure in fisheries. Defining enclosure as the process of concentrating rights and power, the research foregrounds the issues of power imbalances, distributional conflicts, and a lack of knowledge and transparency. Q-methodology is applied to detail the range of views on enclosure in the participating stakeholders. The findings of the thesis suggest that the introduction of both the MSP regime, and the market-led fisheries management system, are not efficiently allocating resources in a rational manner. Rather, institutional change has been steadily influenced by political thinking and powerful actors, so that rights and resources are being concentrated to fewer hands. The research also suggests that a diverse array of understandings of ownership are present in Scotland's seas that are not currently foregrounded in policy. Excluding these forms of ownership will lead to further tensions between users. As such, understanding the marine environment as a series of social institutions is necessary for designing a governance regime that is both equitable and sustainable. By understanding the sources of rights, and how they are performed in concrete relations between individuals, regulators can better address potential conflicts, and avoid destructive enclosure. The research therefore recommends further engagement with stakeholders, and acknowledgement of rights through different participatory or financial channels.

The abyssal environment remains one of the most poorly studied parts of the planet. While predominantly an environment dominated by soft sediments, some abyssal regions are known to harbour potato-sized, rock-like formations known as polymetallic nodules. These nodule provinces are now the subject of exploration by nations and their nominated contractors keen to develop a new deep-sea mining industry. This new industry has the potential for large-scale environmental impacts, but at present these impacts are difficult to predict, and therefore mitigate, as a result of the lack of ecological data and scientific understanding of these areas. The studies carried out in this thesis aimed to contribute to our understanding of the epibenthic megafauna communities in areas targeted for mining, and to support the environmental management of mining activities through informing recommendations on environmental survey design and spatial planning. Imagery from nine transects of 800 m2 in the central Clarion Clipperton Fracture Zone (CCZ) were analysed to describe the epibenthic megafaunal communities at both regional (>1 000 km) and local (2 km) scales. The relationship between biological data derived from image analysis and modelled environmental data was examined to determine potential drivers of community composition and diversity, and rarefaction and extrapolation curves were used to assess levels of sampling required to establish baseline faunal assessments. Finally, clustering algorithms were used to classify broad-scale, modelled environmental data into different habitat types, to assess the effectiveness of the existing protected area network in the CCZ. Megafauna morphotypes most vulnerable to mining, including rare, nodule-specific, suspension feeding, and sessile organisms, formed a large proportion of the CCZ epibenthic megafauna. Several dominant morphotypes were homogenous over large scales, but there was high turnover of rare morphotypes at regional and local scales. In addition, broad-scale bathymetric position index was identified as an important driver of both megafauna and metazoan diversity at regional scales. To characterise the community at 99% sample coverage, sampling units of ~2 800 - 4 600 m2, or 780 - 960 individuals, were required, with 26 - 27 x 800 m2 replicate transects. This sampling effort was much greater than is generally used in the deep sea. Finally, a top-down, broad-scale habitat classification of the CCZ identified 46 habitat types and revealed that many of these were underrepresented in the current protected area network, with several occurring almost exclusively in mining areas. The body of research contained in this thesis suggests that 1) those morphotypes most vulnerable to mining form a substantial proportion of the megafauna communities in the CCZ, 2) greater sampling effort is required to fully characterise baseline environmental conditions of the CCZ, and 3) the current protected area network established in the CCZ does not adequately capture the range of habitats present. This thesis advocates for the use of Regional Environmental Assessment to address some of the pressing issues preventing progress in environmental management of deep-sea mining.

Novel methods are required to improve knowledge on the activity of marine recreational fishers (which can be impactful); the stocks they prosecute, and the ecosystems the fishers and their quarry interact with. "Traditional" survey methods rely on complex randomised designs based on sound statistical sampling methods and are the "gold standard" for evidence collection. But these methods are costly and logistically complex to deliver, which partially explains the relatively poor understanding of marine recreational fisher activity in the majority of recreational fisheries, even in developed countries. This thesis examines two separate (but interlinked) approaches to enhance knowledge acquisition. Firstly, two separate methods are described which use the local ecological knowledge of fishers to describe proxies for the estimation of the spatial and temporal distribution of effort. These proxies are validated against the best available ground truth directed-survey data. One method exploits social media, which can pose unfamiliar ethical questions to ethical research boards and the peers of researchers who propose to use social media. Consequently a review of the ethical issues surrounding the use of social media as a source of scientific data for fisheries research is provided. The second approach automatically derives accurate estimates of a morphological measurement (total length) of the European sea bass (Dichentrachus labrax) under real survey conditions (i.e. with limited control of the camera and related paraphernalia). There were two aspects to the length estimation process; (i) images were corrected for distortion, and length estimates corrected for parallax effects; and (ii) machine vision (transfer learning using three pretrained regional convolutional neural networks) and a machine recognisable marker were used to detect European sea bass in images taken with different cameras and on different angling platforms. These detections, together with the methods validated in (i) provided accurate length estimates with a percent mean bias error of -0.1%.

Coming into force in 2009, the UNESCO 2001 Convention on the Protection of the Underwater Cultural Heritage has grown in reputation as the leading international instrument for the global protection of underwater cultural heritage (UCH). While the Convention introduced a number of positive developments in the international system protecting UCH, there has been a lack of research evaluating the legal framework from a more critical and macro perspective. This study therefore seeks to examine the possible weaknesses which may lie in the sole reliance upon an international treaty, as an instrument developed and enforced through the legal system of public international law. It argues that the multiple-value and global public good nature of UCH makes agreements between states to 'cooperate' in its protection prone to underproduction and poor compliance, when operating within such a consent-based system of law. It then argues that numerous features of Westphalian sovereignty - including sovereign absolutism, equality and territoriality - can each be found at the heart of a struggling system for governing the oceans, which has relied too heavily upon the positivist paradigm of nation state authority and its manifestations through state-led public international law and private international law. Utilising an in-depth literature review across numerous law and governance research fields, as well as interviews with 11 expert respondents in the field of marine and UCH policy, the study examines: (1) what are the challenges relating to cooperation, compliance, and collective action in the protection of UCH if relying on "inter-national" governance, as is envisioned by the use of the UNESCO Convention; and, (2), assuming that new solutions are needed, whether "transnational" governance approaches - operating vertically at multiple policy scales (global-regional-national-local) and utilising private, public and hybrid actors in the provision and enforcement of regulation - might enhance the protection of UCH further. In particular, it seeks to examine whether global governance, regional-level regimes, and community-centred collaborative governance could each provide additional protections for UCH, beyond the horizontal Westphalian paradigm. The findings provide evidence of the weaknesses which would be inherent in the exclusive reliance on the UNESCO Convention and conclude that, in parallel, further efforts must be made to achieve new global, regional, and community policy regimes for UCH protection, operating with, within or without the nation state.

The generation of offshore renewable energy, particularly offshore wind, is a rapidly growing sector internationally. As the offshore wind sector expands, it competes for space with other users. Space competition may result into exclusion and subsequently into conflicts with traditional users, such as commercial fisheries. To help mediate conflicts, balance multiple objectives and move towards more sustainable decision-making, marine spatial planning (MSP) has emerged as the main management tool internationally. By focusing on the interactions between offshore wind and commercial fishing sectors in Scotland, this thesis developed a series of methods and tools to assist resolve conflicts in MSP and form the basis for the longterm co-existence between emerging and established sectors. The research presented here documents the interactions between the two sectors, captures industry perceptions on the nature of cross-sectoral conflicts, provides primary data on the distribution of fishing activity by smaller vessels in Scotland, presents the development of a spatial modelling tool for fisheries displacement due to offshore wind farms, and reviews the current marine licensing regime and practice of Environmental Impact Assessment for offshore wind farms in order to identify strategies to further foster synergistic coexistence between the two sectors. Overall, findings demonstrate the central role for MSP to manage conflicts and promotes synergies. Findings arrive at a critical time for managers, policy makers, and the research community, as several countries around the world are faced with similar challenges (arrival of a new user and claims of exclusivity) with their respective domestic sectors.

Since the turn of the century marine spatial planning and an ecosystem approach have been promoted as a way of managing anthropogenic impacts upon the marine environment. However, more information is needed on how to apply these in practice. This thesis examines the main international and European legal regimes which facilitate and require the implementation of an ecosystem approach to marine management in order to investigate the Scottish approach to marine spatial planning (MSP). The law of the marine environment has, however, evolved in a fragmentary, reactionary manner at an international, European and national level. Drawing out the connections between different legal requirements and the processes, this thesis highlights how the concept of good environmental status (GES) objectifies the elements of the environment that must be considered in order to implement an ecosystem approach to marine management. At a Scottish level, this thesis discusses the law governing the marine renewable energy industry focussing on offshore wind to scrutinise whether the legislation that introduced marine spatial planning in Scottish waters (the Marine (Scotland) Act 2010 and the Marine and Coastal Access Act 2009) can reconcile ambitious renewable energy targets while progressing towards achieving and maintaining good environmental status. Connecting the laws governing strategic environmental assessments and environmental impact assessments with initial assessments under the Marine Strategy Framework Directive (MSFD) identifies how the law can reconcile increasing marine renewable energy production with the obligation to achieve and maintain GES. However, the key to achieving this are the licensing decisions authorising the developments.

Species distribution maps can provide important information to focus conservation efforts and enable spatial management of human activities. Two sympatric marine predators, grey seals (Halichoerus grypus) and harbour seals (Phoca vitulina), have overlapping ranges but contrasting population dynamics around the UK; whilst grey seals have generally increased, harbour seals have shown significant regional declines. A robust analytical methodology was developed to produce maps of grey and harbour seal usage estimates with corresponding uncertainty, and scales of spatial partitioning between the species were found. Throughout their range, both grey and harbour seals spend the majority of their time within 50 km of the coast. The scalability of the analytical approach was enhanced and environmental information to enable spatial predictions was included. The resultant maps have been applied to inform consent and licensing of marine renewable developments of wind farms and tidal turbines. For harbour seals around Orkney, northern Scotland, distance from haul out, proportion of sand in seabed sediment, and annual mean power were important predictors of space-use. Utilising seal usage maps, a framework was produced to allow shipping noise, an important marine anthropogenic stressor, to be explicitly incorporated into spatial planning. Potentially sensitive areas were identified through quantifying risk of exposure of shipping traffic to marine species. Individual noise exposure was predicted with associated uncertainty in an area with varying rates of co-occurrence. Across the UK, spatial overlap was highest within 50 km of the coast, close to seal haul outs. Areas identified with high risk of exposure included 11 Special Areas of Conservation (from a possible 25). Risk to harbour seal populations was highest, affecting half of all SACs associated with the species. For 20 of 28 animals in the acoustic exposure study, 95% CI for M-weighted cumulative Sound Exposure Levels had upper bounds above levels known to induce Temporary Threshold Shift. Predictions of broadband received sound pressure levels were underestimated on average by 0.7 dB re 1μPa (± 3.3). An analytical methodology was derived to allow ecological maps to be quantitatively compared. The Structural Similarity (SSIM) index was enhanced to incorporate uncertainty from underlying spatial models, and a software algorithm was developed to correct for internal edge effects so that loss of spatial information from the map comparison was limited. The application of the approach was demonstrated using a case study of sperm whales (Physeter macrocephalus, Linneaus 1758) in the Mediterranean Sea to identify areas where local-scale differences in space-use between groups and singleton whales occurred. SSIM is applicable to a broad range of spatial ecological data, providing a novel tool for map comparison.

The marine environment provides essential ecosystem services that are critical to the functioning of the earth’s life support system and the maintenance of human well-being. Marine Protected Areas (MPAs) are recognised as being the mechanism though which marine natural capital may be conserved. This thesis focuses on the value associated with marine conservation in a case study area, Lyme Bay, England where a ‘closed area’ was created in 2008. A review of literature spanning 20 years shows that despite sound ecological knowledge of a marine area, the reliance on traditional neo-classical economic valuations for marine spatial planning can obscure other issues pertinent to the ecosystem approach. A further valuation of the marine leisure and recreation industry shows that the industry is of economic significance and that the MPA enables the protection of the most valuable sites but has limited benefits for protecting the full resource base. In terms of ecological value, a ‘service orientated framework’ was developed to enable decision makers to understand the links between benthic species, ecological function and indirect ecosystem services. Results spatially identify which ecosystem services occur and demonstrate the value of the MPA in ensuring delivery of these ecosystem services. In relation to the social value of the MPA the research reveals that support for the MPA is strong amongst the majority of stakeholder groups. Values are expressed as the economic, environmental and social benefits of the MPA. However, there have been clear social costs of the MPA policy and these have been borne by mobile and static gear fishermen and charter boat operators. Each valuation methodology can inform decision making. Though, if ecosystem service valuation is to become a deliberative tool for marine conservation and planning, then there is a need for a larger societal discussion on what activities and trade-offs society considers acceptable.

In the contemporary world, oceans are increasingly realized as ‘threatened places’ in need of environmental protection, at risk from pollution, habitat loss, and overfishing. On the other hand, nations around the world are turning their attention to oceans as a new source of economic development and growth, seeing them as ‘industrialized spaces’. The concept of integrating Ecosystem-Based Management (EBM) and Marine Spatial Planning (MSP) is a new approach for sustainable Ocean Governance (SOG). As an effective strategic tool for planning and managing conflicting ocean uses and their interactions with marine ecosystems, the EBM-MSP approach creates an opportunity for long-term development in relation to ocean and its resources. This thesis scrutinizes the contemporary concepts, definitions, and approaches pertinent to the establishment of a comprehensive Ecosystem-based Management and Marine Spatial Planning (EBM-MSP) framework for Sustainable Ocean Governance that reflects global and regional standards. The study also analyses various scientific data – especially the pollutants’ concentration at spatial and temporal scales – with special reference to EBM-MSP. The research analyses international laws, declarations, conventions, and agreements that are relevant to the proposition of a new dynamic approach to SOG based on EBM-MSP. This new approach could be useful to support necessary reforms, filling gaps in legal regimes and achieving integrated and effective ocean governance mechanisms to prevent, reduce, and control pollution in the marine environment, as well as promoting sustainable exploration of marine resources. Specifically, the research critically analyses the existing legal frameworks in relation to SOG in the Bay of Bengal (BOB). Based on an analysis of sectoral legislation and institutional arrangements in the BOB, the thesis recommends the modification and adoption of legislation, as well as integration among the relevant departments of Bangladesh Government, to match transboundary SOG, particularly along with EBM-MSP development processes. The study focuses on national policies and strategies along with sectoral legislation and institutional arrangements to contribute towards EBM-MSP at national level for SOG, by considering socioeconomic balance and jurisdictional overlays. Based on experiences in the Baltic Sea, Mediterranean Sea, and Great Barrier Reef Marine Park (GBRMP), the research determines numerous key features to assist with the generation and application of EBM-MSP in the BOB region, specifically in Bangladesh, by integrating EBM-MSP with particular reference to a Comprehensive Ocean Zoning (COZ). The substantial outcome of the study is to suggest a COZ Framework for Bangladesh to protect priority seascapes and sites, species of special concern, and their critical habitats, by designing Marine Protected Area networks throughout the transboundary coast.

Abstract: Multi-habitat use is a widespread strategy for marine organisms, including numerous coral reef fish and invertebrate species of ecological and economic importance. Through daily, seasonal, or ontogenetic migrations, these species play vital roles in maintaining functional connectivity, i.e., the exchange of organisms, energy, nutrients, and other matter between habitats in spatially and topographically heterogeneous seascapes. However, stressors operating over multiple spatiotemporal scales, including global ocean warming and acidification, land-use change, and resource overexploitation, are degrading and fragmenting marine habitats, threatening functional connectivity. Identifying, protecting, and restoring habitat patches and corridors responsible for maintaining multi-scale and multi-species functional connectivity is essential for marine conservation. In this thesis, I address key knowledge gaps in our understanding of the spatial and environmental conditions supporting the cross-shelf (> 5 km) ontogenetic migrations of two mesopredatory reef fish species occupying a heavily modified coastal seascape in the Florida Keys, USA—gray snapper (Lutjanus griseus) and bluestriped grunt (Haemulon sciurus). In addition to supporting local fisheries, both species play a critical role in shaping ecosystem function by delivering allochthonous nutrient subsidies and modifying rates of herbivory, corallivory, and predation by other community members, yet their ontogenetic habitat shifts remain difficult to track using conventional techniques due to their small body size at migration and the broad spatiotemporal scales over which they move. In Chapter 2, I first compared two techniques for modeling seascape-wide habitat suitability for the migratory sub-adults of each species—penalized logistic regressions and Maximum Entropy (MaxEnt) modeling—using fish records from SCUBA-diver surveys and high-resolution spatial data on bathymetry, seasonal water conditions, habitat configuration, and seascape surface geomorphology. I found that across species and suitability thresholds, MaxEnt’s discriminatory ability exceeded that of the penalized regressions. Furthermore, MaxEnt’s patchy suitability predictions, which were driven primarily by benthic habitat composition, depth, and broad-scale seafloor features, more closely aligned with the known ecology of the study species. Then, in Chapter 3, I modeled potential functional connectivity for sub-adult L. griseus and H. sciurus using a spatial graph-theoretic approach in which MaxEnt-derived nodes (i.e., suitable habitat patches) and edges (i.e., least-cost paths predicted over species-specific resistance surfaces) were used to quantify and visualize the probability of connectivity at both the local and seascape scales. I then used the resulting connectivity networks to evaluate and rank the contributions of candidate sites prioritized for coral restoration as part of the spatial design of a broad-scale, multi-million dollar (USD) coral reef restoration program recently established in the Florida Keys—Mission: Iconic Reefs—to seascape-wide connectivity. I hypothesized that sites located adjacent to potential mangrove and seagrass nurseries would support higher levels of connectivity for both species, and thus be of the greatest value for restoration. Spatial graph analyses revealed that, across scales, the Florida Keys seascape presently supports a higher level of potential connectivity for sub-adult H. sciurus relative to L. griseus. Moreover, these models suggest that the Mission: Iconic Reefs sites are more likely to benefit from ecological interactions with migrating H. sciurus compared to L. griseus based on their spatial configuration. Contrary to my hypothesis, however, site-specific connectivity contributions were not found to be related to nursery proximity. This thesis demonstrates how spatial graph connectivity analyses informed by habitat suitability modeling can be leveraged as a tool in support of marine habitat restoration planning through the development of data-driven spatial priorities and joins previous research showcasing the ecological benefits of integrating multi-species connectivity in marine reserve design, including productivity and diversity enhancements.

Dynamic ocean management (DOM), a type of marine spatial planning in which management decisions are updated in response to changing environmental, biological, or socioeconomic conditions, holds promise for balancing tradeoffs between conservation and marine resource use. However, as climate change continues to drive unprecedented oceanic changes, it is critical to evaluate how such tradeoffs may vary under different environmental regimes to ensure management strategies remain robust. To address this need, we explored blue whale ship strike management scenarios in the Southern California Bight, USA, an area that currently uses voluntary vessel speed reductions to mitigate risk of lethal ship collisions. We compared two simulated DOM strategies – a ‘daily strategy’ that implemented speed reductions in response to whale habitat conditions on a daily basis, and a ‘seasonal strategy’ that implemented speed reductions in response to whale habitat conditions on a seasonal basis – with a ‘fixed strategy’ that implemented speed reductions for a fixed time period each year, irrespective of environmental conditions. We evaluated the capacity of these strategies to balance tradeoffs between whale conservation and shipping activities over a 17-year study period. Critically, we assessed these tradeoffs before, during, and after a record marine heatwave to evaluate the relative utilities of these strategies during anomalous ocean conditions. Over the 17-year study period, seasonal and daily DOM strategies achieved a 6.4–10.7% improvement in expected whale protection from lethal collision, respectively, without the need for additional vessel speed reductions, as compared to the fixed strategy. The benefit of DOM strategies has grown in the last decade and was accentuated during and after the marine heatwave event, with the daily DOM strategy seeing a 16.2% increase in whale protection compared to the fixed strategy in the five years prior to the event, versus a 26.5% increase in the five years during and after the event. Such results indicate that dynamic ocean management is a valuable strategy for coping with anomalous environmental conditions, which will become increasingly important as the climate continues to change. Moreover, our study emphasizes the importance of assessing tradeoffs between conservation goals and human activities over a range of environmental conditions in order to evaluate the robustness of management strategies to climate change.

Marine aquaculture is the most rapidly growing food sector and has great potential for expansion as part of a sustainable vision for seafood production in the future. Marine spatial planning for aquaculture is crucial to identify the best areas for productivity and profitability and to avoid conflict with other uses of the space. Given that climate change will likely change the answers to these spatial planning questions, effective marine spatial plans for aquaculture must assess expected changes and identify efficient adaptation strategies. To this end, we propose a novel approach to define climate change responsive marine spatial planning of aquaculture. We use the Southern California Bight (SCB) as a case study. First, we focus on understanding the effects of interannual variability over site selection. In Chapters I and II, we use a historical reanalysis of environmental data to run aquaculture models of Mediterranean mussels, striped bass and giant kelp (mussels, fish, and kelp). We use empirical orthogonal functions and principal component analysis to identify spatial and temporal patterns of variability. We found that decadal variability has significant impacts on the productivity and profitability of farms. The different farmed species had quite different responses. Mussels had good productivity regions spread along the coast with the highest productivity in the northern region. By contrast, fish had highest productivity sites in the south given warmer temperatures, but differences among southern sites were small. Kelp production is limited to the northern-most region and productivity differences among sites were striking. Finally in Chapter III, we look to the future and incorporate climate projections up to year 2100 to understand the effects of future climate change on site selection for mussels, kelp, and fish species. Given that mean conditions and interannual variance are both relevant components of climate, we analyzed both effects on future aquaculture productivity. Variability in production is projected to be most striking for kelp, followed by mussels. Fish production actually benefits from warming temperatures, and the increasing trend in the mean predominates over interannual variability. General lessons from historical records and future forecasts suggest that kelp and mussels are more prone to variability given their dependence on nutrients and plankton controlled by ocean conditions. By contrast, since fish are fed in aquaculture, the long term trend in temperature is the biggest driver of fish production. Ignoring variability, therefore, might have greater consequences for the profitable siting of kelp and mussel farms. Monitoring systems are valuable to both characterize productivity variation and to enhance the empirical foundation for better forecasts that can help create climate resilient marine spatial planning. Our results show that spatial patterns of productivity remain consistent despite growing climate variability and climate change until optimal thresholds for growth are reached. Selection of species and sites resilient to current and upcoming environmental conditions are important steps in the planning process. Although this work focuses on a single coastline region, it provides an analytical framework that can be expanded to other regions of the globe to help design optimal adaptation strategies tailored to each region’s specific climate dynamics.

Bangladesh has an extensive maritime area in the Bay of Bengal (BoB), which has high prospects of Blue Economy benefits along with risk of marine pollution. In this context, Bangladesh needs a balanced approach in the exploration of ocean resources for economic benefits and to protect the marine environment. Marine Spatial Planning (MSP) may be a way forward to achieve the balance in the exploration of ocean resources and the protection of the marine environment. Despite of some inadequacies, MSP in the GBR has achieve good progress in Ecosystem-Based Management (EBM) to implement a balanced approach for Sustainable Ocean Governance (SOG) in the Reef region. This experience of the Great Barrier Reef (GBR) may be a lesson for Bangladesh to develop necessary legal and institutional arrangements for the development of MSP. This research analyses the legal and institutional regimes for MSP in the GBR to understand the adequacies for the implementation of MSP, and the current legal and institutional arrangements in Bangladesh for ocean governance to understand the regulatory frameworks for management of marine resources in the BoB. The research conducts a comparative analysis of the legal and institutional regimes for the governance and management of ocean space of Bangladesh and the GBR in order to explore the prospects and challenges for the development of MSP in Bangladesh. The research addresses the legal regimes for MSP under international and regional instruments in order to apply them to pre-judges the development of MSP for governance at the national level. The research concludes with recommendations for necessary law reforms and institutional changes for the development of MSP in Bangladesh to facilitate sustainable governance in the BoB. The research thus determines adequate legal and institutional arrangements for the development of MSP in Bangladesh to achieve sustainable governance in the BoB.

Located within Australia’s largest city, the iconic Sydney Harbour sustains a highly diverse marine environment, where local managers operate within a layered and complex governance structure that is yet to adopt a holistic integrated approach to resource management. Planning a sustainable future for our sea-bounded society requires enhanced understanding of the responses of natural and socio-economic systems to human actions, and improved management of the multiple human uses of our marine ecosystems. Recent criticism to marine resource management systems in the Sydney Harbour catchment area include lack of integration of interactions between ecological and social systems; poor definition of management targets and outcome-oriented management plans; and insufficient integration between catchment and coastal planning. Integrated resource planning and management can address identified weaknesses, and Ecosystem-Based Marine Spatial Planning (EBA-MSP) offers a strategic framework that can facilitate a more structured approach to resource planning, recognizing the full array of interactions within ecosystems, including human uses. This research proposed the adoption of the EBA-MSP framework to improve the methodological approach to resource planning and enhance the integration of the social dimension into management plans, using Manly Local Government Area as a representative catchment area of the harbour. The research aimed to enhance local government capacity to develop integrated coastal management plans consistent with EBA-MSP principles, accounting for key social, economic and environmental factors relevant to a sustainable management of the harbour. In fulfilling this aim, the research established specific objectives of appraising EBA-MSP case studies, assessing coastal planning and resource management plans at local scale, identifying and characterising socio-economic and biological targets, and designing and developing a prototype Decision Support Tool (DST) based on a Bayesian Belief Network (BBN) to support planning processes. This research provides initial theoretical and practical foundations for local government to adopt EBA-MSP as an overarching planning framework that can deliver healthy resilient marine ecosystems sustaining human uses. The BBN-based DST developed here can play an important role in continuing to increase government capacity to develop integrated resource management plans under an EBA-MSP approach.

Aquaculture is currently the fastest growing food sector in the world, and the oceans are seen as one of the most likely areas for expansion. Marine aquaculture holds immense potential for alleviating food security concerns, revitalizing coastal communities, and spearheading blue development initiatives. However, the growth of aquaculture also presents risks to the environment and other uses and goals in the marine environment. Within the context of likely future expansion, the research presented assesses the development trajectories of marine aquaculture and examines opportunities for conservation focused development. In this dissertation, I present three separate studies focused on different aspects of aquaculture development and conservation. The first chapter develops a framework for marine spatial planning for offshore aquaculture. The second chapter considers the global potential for marine aquaculture development and assesses the areas that have the most favorable physical and biological characteristics for aquaculture growth. The third chapter investigates when conservation-motivated wildlife farming could be a successful market mechanism to alleviate poaching pressure on threatened species.I take a multidisciplinary approach to answering these diverse questions, integrating spatial and ecological modeling, ecological and economic theory, and data and literature synthesis. Key results include that the productivity and environmental impact of aquaculture vary spatially, but that spatial management can be used to maximize value and create synergies with other ocean management objectives (Chapter 1); global scale development potential for marine aquaculture far exceeds the space required to meet foreseeable seafood demand and that suitable space is unlikely to limit marine aquaculture development (Chapter 2); and that aquaculture may be a promising market solution particularly well suited to many threatened aquatic species, especially those that can be farmed relatively cheaply (Chapter 3). Taken together these studies make an important contribution to the field of aquaculture science and provide foundational information on the potential and opportunities for aquaculture development.

The nearshore reef environment in Hawai‘i is impacted by a wide range of human activities. As a result of these anthropogenic stressors, economic and sociocultural benefits to communities in Hawai‘i have diminished over time. Understanding the spatial distribution, intensity, overlap, and cumulative impact of human activities is essential for effective marine management and protection of ecosystem services generated by coral reefs. Currently, this kind of information is not readily available to resource managers and policy makers in Hawai‘i. This research used existing data and novel approaches to produce maps for some of the most important anthropogenic stressors on coral reefs in Hawai‘i. To accomplish this, I compiled a comprehensive database, synthesized a suite of spatial datasets into a unified framework, and devised geospatial methodologies to produce statewide maps of anthropogenic stressors including: fishing pressure, land-based pollution, habitat modification, invasive species, marine debris, and climate change. Expert knowledge surveys were conducted to assess the vulnerability of three nearshore habitat types to anthropogenic stressors. The resulting vulnerability weighting factors for stressor-habitat pairs were used to produce continuous maps of cumulative impacts across the Main Hawaiian Islands. Experts ranked fishing as the most impactful stressor to coral dominated and other hard bottom habitats. Invasive species were another major concern for Hawai’i experts, which differs from other global surveys of coral reef experts. Coral dominated hard bottom habitat was both the most vulnerable to stressors and the most impacted across the Main Hawaiian Islands. Human population density was shown to be a poor proxy for this approach to map cumulative anthropogenic impacts. Spatial datasets developed by this study are available for use in future research on patterns of reef state and coral reef degradation. These maps also directly benefit management by identifying what places and habitat types are most impacted, which drivers should be of greatest concern in different areas, and where different management strategies (e.g., regulations, restoration, enforcement, or increased monitoring) should be prioritized.

Despite advances in global ecosystem management, natural resource planning still often fails to incorporate cultural preferences and values. Spatial planning methods, particularly in coastal and marine contexts, tend to rely on data that relate biophysical processes and economic sector revenue. Consequently, a ‘missing layer’ of data that captures the people and communities involved prevents spatial planning from achieving its full potential (St. Martin and Hall-Arber, 2008). A critical question is therefore: how is decision-making within spatial planning affected by considering people’s ecosystem-related values and management preferences, in addition to layers of biophysical and economic sector data?To address this over-arching question, this study employed integrated qualitative and quantitative research methods to examine (1) how mixed field research methods can shed light on which management paths to pursue when faced with tradeoffs among the various benefits provided by nature, (2) how people in developing world contexts who depend more directly on nature’s tangible benefits (e.g., livelihood sources) value intangible cultural benefits provided by ecosystems, and (3) how information on the cultural benefits of nature can inform environmental decision-making. In so doing, this study presents a methodological framework to elicit people’s ecosystem-related values and management preferences, shows how to decipher the importance of nature’s intangible benefits to the wellbeing of natural-resource dependent communities, and shares lessons learned from integrating the cultural benefits of nature into decisions concerning rural, undeveloped coastline in the Chiloé Archipelago, Chile.

In the context of the New Zealand Energy Strategy-target of 90% electricity generation from renewable energy by the year 2025, this dissertation analyses if the generally accepted statement that socio-economic factors and in particular planning procedures and public acceptance of individual schemes are a major limitation for the development of renewable energy projects, also applies in New Zealand. Moreover, it is analysed if a relocation of renewable power generation to the coastal and marine environment, in particular in form of offshore wind farms, could circumvent this obstacle. Therefore New Zealand’s spatial planning framework on land and in the marine environment is analysed using parts of the comparative policy analysis. Furthermore, the consent processes and the public perceptions via submissions of three different case studies, two wind farms on land and a tidal power generation scheme in the marine environment are examined with a framework which is partly based on Devine-Wright (2005) and Graham et al (2009). It is ascertained that the resource consent process on land can be an obstacle in the realisation of new wind farms, mainly due to time and cost consuming procedures and strong public opposition. The relocation of projects into the marine environment does not circumvent of facilitate the consenting process, but potentially reduces public opposition if appropriate locations are chosen and their allocation is strategically provided for in the spatial planning framework. This however requires changes to the existing planning system of New Zealand’s marine environment