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In an effort to deliver better outcomes for people and the ecosystems they depend on, many governments and civil society groups are engaging natural resource users in collaborative management arrangements (frequently called comanagement). However, there are few empirical studies demonstrating the social and institutional conditions conducive to successful comanagement outcomes, especially in small-scale fisheries. Here, we evaluate 42 comanagement arrangements across five countries and show that: (i) comanagement is largely successful at meeting social and ecological goals; (ii) comanagement tends to benefit wealthier resource users; (iii) resource overexploitation is most strongly influenced by market access and users' dependence on resources; and (iv) institutional characteristics strongly influence livelihood and compliance outcomes, yet have little effect on ecological conditions.

In an effort to deliver better outcomes for people and the ecosystems they depend on, many governments and civil society groups are engaging natural resource users in collaborative management arrangements (frequently called comanagement). However, there are few empirical studies demonstrating the social and institutional conditions conducive to successful comanagement outcomes, especially in small-scale fisheries. Here, we evaluate 42 comanagement arrangements across five countries and show that: (i) comanagement is largely successful at meeting social and ecological goals; (ii) comanagement tends to benefit wealthier resource users; (iii) resource overexploitation is most strongly influenced by market access and users' dependence on resources; and (iv) institutional characteristics strongly influence livelihood and compliance outcomes, yet have little effect on ecological conditions.

INTRODUCTION: THE REEF PHENOMENON -- INTO THE INTIMACY OF CORALS, BUILDERS OF THE SEA -- 1 TAXONOMIC AFFILIATION -- 1.1 Systematic classification of cnidarians -- 1.2 Scleractinians -- 2 MORPHOLOGY AND ANATOMY -- 2.1 Polyp anatomy -- 2.2 Reproduction -- 2.2.1 Sexual reproduction -- 2.2.2 Asexual reproduction -- 2.3 Anatomy of calcareous skeletons -- 2.4 Coral colonies -- 2.4.1 Corallite arrangement -- 2.4.2 Colony morphology -- 3 SYMBIOSIS -- 4 BIOMINERALIZATION -- 4.1 Calicoderm and biomineralization -- 4.2 Skeletons and biomineralization -- 4.3 Interface between calicoderm and skeleton -- 4.4 Principles of calcification -- 5 NUTRITION -- 5.1 Prey capture -- 5.2 Food -- 5.3 Autotrophy -- THE MODERN TIMES -- 1 BIOZONATION -- 2 REEF MORPHOTYPES -- 2.1 Fringing reefs -- 2.2 Barrier reefs -- 2.3 Atolls -- 2.4 Bank reefs -- 2.5 High carbonate islands -- 3 GEOGRAPHICAL DISTRIBUTION -- 3.1 Ecological control -- 3.2 Tectonic control -- 3.3 Eustatic control -- 3.4 Topographic control -- 4 REEF GROWTH -- 4.1 Vertical growth strategies -- 4.1.1 Controlling factors -- 4.1.2 Give-up growth -- 4.1.3 Keep-up growth -- 4.1.4 Catch-up mode -- 4.2 Lateral growth -- 5 MORPHO-SEDIMENTARY PROCESSES -- 5.1 Bioconstruction -- 5.2 Erosion -- 5.3 Bioaccumulation -- 5.4 Cementation -- 6 INTERNAL STRUCTURE -- 6.1 Nature and distribution of facies -- 6.1.1 Framework facies -- 6.1.2 Detrital facies -- 6.1.3 Facies distribution and hydrodynamics -- 6.2 The different structural models -- 7 A BRIEF HISTORY OF REEF DEVELOPMENT -- 7.1 The climatic context -- 7.2 History of reef development since the last deglaciation -- 7.3 Reef history throughout the Pleistocene -- 8 RECORD OF ENVIRONMENTAL CHANGES -- 8.1 Record at the coral colony scale -- 8.1.1 Temperature -- 8.1.2 Salinometry -- 8.1.3 Rainfall -- 8.1.4 pH measurement -- 8.1.5 Photometry -- 8.1.6 Current measurement -- 8.2 Record at the scale of a reef edifice -- 8.2.1 Reef flats and micro-atolls -- 8.2.2 Arrangement of coral communities -- 8.2.3 Arrangement of reef edifices -- THE LONG MARCH OF CORALS -- 1 THE TIME OF THE ORIGINS -- 1.1 Early Earth and the first traces of life -- 1.2 Evolution of the atmosphere -- 1.3 Geochemical model of the early ocean -- 1.4 Emergence of biomineralization -- 1.5 The early calcifying organisms and cnidarians -- 1.6 The earliest corals -- 1.7 The appearance of scleractinian corals -- 2 THE TIME OF DIVERSIFICATION -- 2.1 Coral-algae symbiosis -- 2.1.1 Acquiring photosymbiosis -- 2.1.2 Evidence of photosymbiosis -- 2.1.3 Symbiosis and coloniality -- 2.2 A brief history of coral and reef building -- 2.2.1 Paleozoic times -- 2.2.2 Mesozoic times -- 2.2.3 Cenozoic times -- THE HIGHS AND LOWS OF THE REEF PHENOMENON -- 1 CAUSES -- 1.1 Causal relationships -- 1.2 Gas emissions and volcanic products -- 1.3 Methane emissions -- 1.4 Thermogenic gases -- 1.5 The fall of celestial bodies -- 1.6 Behaviour of organisms facing environmental disturbances -- 1.7 Disturbances induced by CO2 and ocean acidification -- 1.8 Thermal shocks -- 1.9 Disturbances induced by ocean deoxygenation -- 2 THE MAIN BIOLOGICAL CRISES -- 2.1 The Cambrian crises -- 2.2 The major crisis of the Ordovician end -- 2.3 The minor crises of the Silurian -- 2.4 The successive crises of the Devonian -- 2.5 The Permian crises -- 2.6 The Triassic crises -- 2.7 The lower Jurassic crisis -- 2.8 The Jurassic–Cretaceous transition (J–K) -- 2.9 The Cretaceous–Paleogene crisis -- 2.10 The Paleocene–Eocene crisis -- 2.11 The Eocene–Oligocene transition -- 2.12 The Oligocene end to the Plio-Quaternary -- 3 THE RESPONSE OF CORALS AND REEFS TO CRISES: FROM EXTINCTION TO RECOVERY -- 3.1 At the Ordovician end -- 3.2 During the Silurian -- 3.3 During the Devonian -- 3.4 At the Permian -- 3.5 At the Permian–Triassic boundary -- 3.6 From the middle to the end of the Triassic -- 3.7 During the Jurassic -- 3.8 From the upper Jurassic to the lower Cretaceous -- 3.9 At the Cretaceous–Paleogene (K–Pg) transition -- 3.10 From the Paleocene to the Eocene -- 3.11 From the Oligocene to the Miocene -- 3.12 During the Plio-Quaternary -- 4 CONCLUSIONS -- CORAL REEFS IN THE FACE OF THEIR FATE -- 1 DISRUPTIVE AGENTS IN ACTION -- 1.1 Carbon dioxide and rising surface water temperatures -- 1.2 Carbon dioxide and its effects on the carbonate cycle -- 1.3 Carbon dioxide and ocean acidification -- 1.4 The other disruptive agents -- 2 THE RESPONSE OF CORALS AND CORAL REEFS -- 2.1 Temperature rise of surface waters -- 2.2 To acidification -- 2.3 To other disruptive agents -- 3 THE EVOLUTION OF CORAL ISLETS -- 3.1 The modes of low-lying island formation -- 3.2 Future evolution of low-lying islands: maintenance, reduction, or destruction? -- CONCLUSIONS -- BIBLIOGRAPHY -- INDICE.

2-s2.0-85062877382 ; In the vast tropical Pacific Basin islands, corals reef ecosystems are one of the defining marine habitats, critical for maintaining biodiversity and supporting highly productive fisheries. These reefs are also vital for tourism and armoring exposed shorelines against erosion and other storm-related effects. Since the 1980's, there has been growing evidence that these Pacific Basin coral reef ecosystems are highly vulnerable to the combined effects of both climatic and non-climatic stressors. Observations of widespread bleaching in the region has been linked to acute temperature stress, and the heightened recurrence intervals and intensity of storms has been correlated to recent climate-change induced impacts. Ocean acidification is another ubiquitous stressor with dramatic consequences to biological systems. In this paper we describe what sets this region apart from other coral reef regions around the world, and highlight some examples of the diverse response to ocean acidification threats and associated socio-economic impacts. © 2019 ; U.S. Department of State, DOS ; Foremost, the authors are deeply saddened by the unexpected passing of Ruth on October 25, 2018. Ruth was an exceptional scientist and pioneer in the field of coral reef biology who worked tirelessly on a 'super coral' that would be better poised against the damaging effects of climate-change, such as ocean acidification and ocean warming. Her life and work is a testament to what can be achieved through scientific innovation and infectious optimism. This work was supported in part by the IAEA Environment Laboratories and the U.S. Department of State through the Junior Professional Officer program (ML). The IAEA is grateful for the support provided to its Environment Laboratories by the Government of the Principality of Monaco . PWS thanks Ms Theresa Fregoso (USGS — Santa Cruz, CA USA) for graphics assistance.

State immunity — Jurisdictional immunity — Foreign government — Hire of vessel — Commercial purposes — Whether immune from suit — Doctrine of restrictive sovereign immunity — Admiralty jurisdiction — Government-owned shipJurisdiction — Admiralty jurisdiction — Convention Relating to the Arrest of Seagoing Ships, 1952 — Effect of "sister ship" jurisdiction — Ship owned by Tongan Government — Arrest of ship in New Zealand — Action in rem — Claim in respect of another ship — Question of possession and control — Jurisdiction under the Admiralty Act 1973 — Plea of sovereign immunity by the Government of Tonga — The law of New Zealand

Ecology, spatial competition, benthic community dynamics, ecological modelling, complex systems, coral reef resilience. - Coral reefs, rainforests of the sea, are of greatest ecological and economical importance. Although they cover just a small fraction of sea floor, they provide indispensable functions for the associated flora and fauna, and invaluable services for livelihoods of large human populations in tropical coastal regions. Within the last few decades coral reefs have been increasingly endangered for various reasons, which can be directly or indirectly ascribed to anthropogenic influence. Chronic stresses can undermine the resilience of coral reefs, which then become more susceptible to the effects of pulse stresses, like hurricanes or thermally induced bleaching. Such an event may then diminish relevant ecosystem properties beyond a threshold, and thus trigger a sudden shift to an alternative state, which may not be in favour of corals but an alternative live form that then achieves dominance. In my thesis I developed a spatially explicit individual-based model to simulate a benthic reef community, typical for a reef in the Western Indian Ocean region. The application was then used to explore key variables and -processes for resilience and to identify potential triggers for phase shifts. Several coral species with contrasting life histories and algae compete for space under different environmental influences. Evoked by direct neighbourhood-interactions and individual responses to environmental conditions, the system performs dynamic self-organisation, and properties of superordinate hierarchical levels (population, community) emerge as a consequence. In multiple scenarios I tested the influences of (i) two different perturbation types (bleaching and mechanical disturbances), -intensities and frequencies, as well as (ii) various levels of grazing and recruitment on the dynamics of coral reef communities. As the results show, perturbations can generate heterogeneous outcomes. While extreme temperature events render a disadvantage for more susceptible branching coral species, these species can dominate under high frequencies of mechanical disturbance events, because they recolonize empty space faster, due to their faster growth rates. Low disturbance levels always benefit the dominance of massive growth forms and a combination of both perturbations at intermediate levels leads to high evenness in the community composition. The results additionally confirm, that herbivory and recruitment are crucial processes for the resilience and persistence of coral reefs. This study also highlights the importance of a diversified analysis of coral reef dynamics to understand the full magnitude of consequences, caused by environmental change. The presented application renders an excellent tool (a) to integrate current knowledge, which can be kept up to date with little effort and (b) can be coupled with other modelling systems that operate on different spatial and temporal scales. Complexity and non-linear dynamics of coral reef functioning can thus be simulated and analysed with a high level of detail and informative value.

Lembeh reefs and its water surrounding are among the richest and most diverse in marine biota in Indonesia. The biota and reefs in this area have an important contribution to the province's economy in the form of tourisms and fishery activities. An inventory using line intercept transect and free collection on the coral diversity has been conducted in four different locations showed that live coral cover ranging from 12.2–60.7% while sand rubble ranged from 4.67 to 78.67%. Among the life form categories, sponge dominated other biota with 0.47–21.97% coverage. Macro algae and turf algae cover were low at all sites, with average less than 2.07%. A total of 193 corals species belonging to 68 genera were recognized from this area. The differences among sites may be consequences of water quality, habitat variability and condition of the land base activities. Water turbidity in the coastal area of Kema was high due to the effects of water discharge from river mouth. Further, poor land management, development of port and human settlement leading to sedimentation, water pollution and poor water quality, remain the primary causes of reefs declines. Busy harbor and local sea transportation will be the major cause of coral reef degradation in the near future. There is a need to increase awareness of local people about the important of coral reefs and to develop management and conservation efforts involving scientists, academe and tourist operators. In addition, it is a need to strengthen the capabilities and capacities of institutions that concern reef management and enforce legislation.Â

In order to ensure the sustainable management of reef fisheries, it is necessary to obtain data about the effects of these fisheries on both fish resources and the ecosystems that sustain them. Ecosystem-based surveys provide this information, but are difficult to implement because of technical, financial and human resources requirements. In this regard participatory assessment methods have the potential to increase the amount of data collected at low cost, while taking advantage of local traditional ecological knowledge. In order to investigate the reef fishery of Toliara Bay, southwest Madagascar, we used participatory fish survey and interview data collected on site. These methods included: (i) monitoring of catch landings during six months by wholesale fish merchants, (ii) household surveys of fishing catch and effort and fish consumption conducted by school children, and (iii) semi-structured interviews of reef users. One thousand five hundred and eighty six fishing trips were sampled between September 2006 and February 2007, 326 households were surveyed by trained school children in January 2007, and 70 reef users were interviewed in July/August 2006. Data collected by participants have been compiled and compared to reference values when available, allowing an assessment of the sustainability of the reef fishery. The results of this study confirm the unsustainable nature of resource exploitation and underline the need for rapid management responses in order to reverse this trend. It also highlights the great potential of participatory assessment methods for gathering large amounts of relevant information on the status and evolution of the ecosystem upon which the fishery depends, while promoting education and awareness about the protection and sustainable use of natural resources. RÉSUMÉ Bien que les pêcheries récifales ne contribuent que marginalement aux captures de pêche mondiales, elles restent une source majeure de revenus et de protéines pour des millions de personnes, en particulier dans les pays en voie de développement. Afin de s'assurer de la bonne gestion de ces pêcheries, il est nécessaire de disposer d'informations sur l'état des ressources et des écosystèmes dont elles dépendent. Mener de telles études est d'autant plus compliqué que les pêcheries en milieu corallien portent sur un large éventail de stocks et d'espèces de poissons, concernent de nombreux pêcheurs et supposent diverses méthodes de captures, et empruntent un grand nombre de canaux de distribution. De plus, ces pêcheries sont souvent considérées de moindre valeur par les gouvernements qui leur octroient donc peu de moyens humains et financiers. Face à ces problèmes, l'implication de la société civile dans les programmes de suivi, appelé suivi participatif, semble en mesure d'apporter des solutions, d'autant que les suivis participatifs présentent l'avantage d'accroître le nombre de données collectées à moindre coût, tout en profitant des connaissances écologiques empiriques qui sont disponibles localement. Afin d'évaluer la pérennité de la pêcherie récifale de la baie de Toliara dans le sud ouest de Madagascar, des méthodes de suivi participatif ont été expérimentées. Ces méthodes consistent à mettre en œuvre : (i) des suivis des débarquements pendant six mois impliquant des mareyeuses, (ii) des enquêtes auprès des ménages, réalisées par des écoliers préalablement formés, afin de recueillir des informations sur l'effort de pêche, les captures et la consommation de poisons, (iii) des entretiens semi-directifs avec des usagers du milieu marin. Ainsi, entre 2006 et 2007, 1586 sorties de pêche ont été échantillonnées, et 326 ménages et 70 usagers ont fait l'objet d'enquêtes. Les données collectées par les membres de la communauté locale ont été analysées afin d'évaluer la pérennité de la pêcherie dans la baie de Toliara. Les résultats de l'étude confirment une exploitation non pérenne et soulignent la nécessité de mettre en place des mesures de gestion afin d'inverser la tendance de détérioration des écosystèmes de la baie. Il ressort également de cette étude que l'implication de la société civile s'avère être pertinente pour recueillir des informations sur les pêcheries récifales à faible coût. En effet, de part le nombre, la qualité, la variété et la pertinence des informations produites, les suivis participatifs contribuent utilement à l'évaluation des pêcheries récifales. Cette expérience met également en évidence le fort potentiel des suivis participatifs à contribuer au renforcement des connaissances et des capacités des communautés locales dans le domaine de la gestion des ressources marines. Ainsi, face au difficile contexte socio-économique et politique qui prévaut actuellement à Madagascar, cette approche s'avère particulièrement prometteuse pour améliorer la gestion des pêcheries traditionnelles grâce à la production d'informations sur ces pêcheries et une plus grande implication des communautés locales dans le processus de gestion.

Benthic community structure, Galápagos, tropical rocky reef, seasonality, upwelling, succession, exclusion experiments, grazing, subtidal, stable isotopes. - Tropical subtidal rocky reef communities are less prominent than coral reefs and characterized by macroalgae, mobile invertebrates, reef fish and diverse communities of epibenthic invertebrates. In the Galápagos Marine Reserve, more than 80% of the shallow benthic habitats are rocky lava reefs. In order to examine the effects of small-scale differences in oceanographic regimes, two rocky reef study sites, an upwelling and a non-upwelling site, were chosen off Floreana Island. The benthic community structure of the sites was studied for two years by subtidal monitoring. Simultaneously, benthic succession studies and grazer exclusion experiments were conducted at both sites. Further, the food web structure for Floreana Island was analyzed by using the stable isotope approach.Results revealed significant differences between both study sites. These findings reflect the particular oceanographic setting of the Galápagos Archipelago and that Floreana Island may also represent a â model systemâ to investigate ecological responses along abiotic gradients.

Microbially mediated processes contribute to coral reef resilience yet, despite extensive characterisation of microbial community variation following environmental perturbation, the effect on microbiome function is poorly understood. We undertook metagenomic sequencing of sponge, macroalgae and seawater microbiomes from a macroalgae-dominated inshore coral reef to define their functional potential and evaluate seasonal shifts in microbially mediated processes. In total, 125 high-quality metagenome-assembled genomes were reconstructed, spanning 15 bacterial and 3 archaeal phyla. Multivariate analysis of the genomes relative abundance revealed changes in the functional potential of reef microbiomes in relation to seasonal environmental fluctuations (e.g. macroalgae biomass, temperature). For example, a shift from Alphaproteobacteria to Bacteroidota-dominated seawater microbiomes occurred during summer, resulting in an increased genomic potential to degrade macroalgal-derived polysaccharides. An 85% reduction of Chloroflexota was observed in the sponge microbiome during summer, with potential consequences for nutrition, waste product removal, and detoxification in the sponge holobiont. A shift in the Firmicutes:Bacteroidota ratio was detected on macroalgae over summer with potential implications for polysaccharide degradation in macroalgal microbiomes. These results highlight that seasonal shifts in the dominant microbial taxa alter the functional repertoire of host-associated and seawater microbiomes, and highlight how environmental perturbation can affect microbially mediated processes in coral reef ecosystems. ; Australian Government Department of Industry, Innovation and Science; Advance Queensland PhD Scholarship Great Barrier Reef Marine Park Authority Management Award National Environmental Science Program (NESP) ; info:eu-repo/semantics/publishedVersion