Advances in ocean observing technologies and modeling provide the capacity to revolutionize the management of living marine resources. While traditional fisheries management approaches like single-species stock assessments are still common, a global effort is underway to adopt ecosystem-based fisheries management (EBFM) approaches. These approaches consider changes in the physical environment and interactions between ecosystem elements, including human uses, holistically. For example, integrated ecosystem assessments aim to synthesize a suite of observations (physical, biological, socioeconomic) and modeling platforms [ocean circulation models, ecological models, short-term forecasts, management strategy evaluations (MSEs)] to assess the current status and recent and future trends of ecosystem components. This information provides guidance for better management strategies. A common thread in EBFM approaches is the need for high-quality observations of ocean conditions, at scales that resolve critical physical-biological processes and are timely for management needs. Here we explore options for a future observing system that meets the needs of EBFM by (i) identifying observing needs for different user groups, (ii) reviewing relevant datasets and existing technologies, (iii) showcasing regional case studies, and (iv) recommending observational approaches required to implement EBFM. We recommend linking ocean observing within the context of Global Ocean Observing System (GOOS) and other regional ocean observing efforts with fisheries observations, new forecasting methods, and capacity development, in a comprehensive ocean observing framework.
This research examines perceptions of the linkages between ecosystem services (ES) and social wellbeing in a small-scale fishing community in Bluefields, Jamaica. It analyzes the perceived changes to these linkages based on the impacts of a marine protected area (MPA) on this coastal social-ecological system. MPAs can have positive long-term social and ecological effects, but in the short-term they can negatively impact communities, and careful attention to these impacts is needed to achieve positive conservation outcomes. We conducted 42 semi-structured interviews and six focus groups discussions with community members in Bluefields. Key findings from this research include: 1) the importance of provisioning (e.g., fish, lobster) and cultural ES (e.g., cultural heritage, bequest values) and their bundled qualities to both fishers and non-fishers; 2) the perceived impact of the MPA is highest for inshore fishers, while offshore fishers/non-fishers reported few/no negative impacts; and 3) inshore fishers perceive being more marginalized in governance processes, despite reporting the greatest negative change to ES access and social wellbeing from MPA implementation. The results suggest that governance processes for coastal conservation must acknowledge the individual and shared values of coastal areas and traditional livelihoods to achieve long-term legitimacy and support.
Uncertainty is inherent in ecosystem modelling, however its effects on modelling results are often poorly understood or ignored. This study addresses the issue of structural uncertainty or, more specifically, model resolution and its impact on the analysis of ecosystem vulnerability to threats. While guidelines for node assignments exist, they are not always underlined with quantitative analysis. Different resolutions of a coral reef network are investigated by comparing the simulated network dynamics over time in various threat scenarios. We demonstrate that the error between a higher-resolution and a lower-resolution models increases, first slowly then rapidly with increased degree of node aggregation. This informs the choice of an optimal model resolution whereby a finer level of a food web representation yields only minimal additional accuracy, while increasing computational cost substantially. Furthermore, our analysis shows that species biomass ratio and the consumption ratio are important parameters to guide node aggregation to minimize the error.
Improving the use of scientific evidence in conservation policy has been a long-standing focus of the conservation community. A plethora of studies have examined conservation science-policy interfaces, including a recent global survey of scientists, policy-makers, and practitioners. This identified a list of top barriers and solutions to evidence use, which have considerable overlap with those identified by other studies conducted over the last few decades. The three top barriers – (i) that conservation is not a political priority, (ii) that there is poor engagement between scientists and decision-makers, and (iii) that conservation problems are complex and uncertain – have often been highlighted in the literature as significant constraints on the use of scientific evidence in conservation policy. There is also repeated identification of the solutions to these barriers. In this perspective, we consider three reasons for this: (1) the barriers are insurmountable, (2) the frequently-proposed solutions are poor, (3) there are implementation challenges to putting solutions into practice. We argue that implementation challenges are most likely to be preventing the solutions being put into practice and that the research agenda for conservation science-policy interfaces needs to move away from identifying barriers and solutions, and towards a detailed investigation of how to overcome these implementation challenges.
Human-made marine habitats such as artificial reefs are used to mitigate marine habitat degradation and aid conservation of species at risk. We used ROV and sonar to survey threatened rockfish (Sebastes spp.) and other groundfish species associated with 18 artificial and natural reefs along the south coast of BC, Canada. Using an information-theoretic approach, we found that community composition significantly differed between natural and artificial reefs. Artificial reefs had high variability in rockfish abundance, some supporting very high or low relative abundance. Natural reefs consistently supported intermediate rockfish abundances. Groundfish diversity was significantly greater on natural reefs than artificial reefs. Depth and relief were significant predictors for both abundance and species richness. Interestingly, rockfish abundance was negatively associated with proximity to nearest rockfish conservation area. This research is a first step in understanding causal mechanisms leading to differences between fish communities on artificial reefs in our study system, and which reef attributes may facilitate successful contributions to conservation. Though artificial reefs show promise in the conservation of some threatened species, the maintenance of diverse fish communities depends on protection of heterogenous natural reef communities.
Marine biota is currently exposed to plastic pollution. The biological effects of plastics may vary according to polymer types (e.g. polystyrene, polyethylene, acrylate), size of particles (macro, micro or nanoparticles) and their shape. There is a considerable lack of knowledge in terms of effects of nanoplastics (NP) to marine biota particularly of polymers like polymethylmethacrylate (PMMA). Thus, this study aimed to assess its ecotoxicological effects using a battery of standard monospecific bioassays with four marine microalgae (Tetraselmis chuii, Nannochloropsis gaditana, Isochrysis galbana and Thalassiosira weissflogii) and a marine rotifer species (Brachionus plicatilis). The tested PMMA-NP concentrations allowed the estimation of median effect concentrations for all microalgae species. T. weissflogii and T. chuii were respectively the most sensitive (EC50,96h of 83.75 mg/L) and least sensitive species (EC50,96h of 132.52 mg/L). The PMMA-NP were also able to induce mortality in rotifers at concentrations higher than 4.69 mg/L with an estimated 48 h median lethal concentration of 13.27 mg/L. A species sensitivity distribution curve (SSD), constructed based on data available in the literature and the data obtained in this study, reveal that PMMA-NP appears as less harmful to marine biota than other polymers like polystyrene.
While plastic items like bottles, bags, and balloons are highly visible litter and well-known as ugly eyesores and hazards to wildlife, there is another form of plastic that is generally not visible but is far more numerous and may be equally or more hazardous in the environment. This is microplastic, small pieces ranging from 5 mm in size down to microscopic. Microplastics are categorized as primary microplastic – that which was always tiny, and secondary microplastic-which results from the fragmentation of larger pieces. As with larger pieces, microplastics represent a variety of different polymers, such as polyethylene, polystyrene, etc. They are found in a variety of shapes, including spheres, fragments, films, and fibers. In the past decade there has been a great amount of study on microplastics – where they come from, where they are found, how organisms interact with them, and what effects they may have on the organisms and the ecosystem. Most of these studies have focused on the marine environment since that is where they were initially detected, but they have subsequently been found to be abundant in freshwater and terrestrial environments as well. This review examines the research, emphasizing aquatic environments, and suggests avenues for improving future research.
Marine microplastic particles (MPs,<5 mm) exhibit wide ranges of densities,sizes, and shapes, so that the entire MPs“ensemble”at every time instant can be character-ized by continuous distributions of these parameters. Accordingly, this community ofparticles demonstrates distributions of dynamical properties, such as sinking or risingvelocity, critical shear stress, and the re-suspension threshold. Moreover, all the MPs’properties vary significantly with the time spent in marine environment and withparticular conditions experienced by the particle on its journey. A brief review of thepresent-day numerical efforts towards prediction of MPs transport shows the prevalenceof the Lagrangian particle tracking approach, especially for floating litter. In a broadercontext, the present practice of MPs transport modelling follows the“selective”strategy(e.g., only a certain sub-class of MPs, or specific processes, are considered, sometimes in onlyone- or two-dimensional setting). The heterogeneous nature of MPs, their enormous longevityand movability in marine environment, and the wide spectrum of the involved environ-mental processes suggest further integration (or coupling) of different models in future, aswell as application of other types of models (ensemble modeling, chaos theory approaches,machine learning, etc.) to the problems of MPs transport and fate in the marine environment.Key words:microplastics, transport, modelling.
The dissemination of marine environmental protection information in social networks is not comprehensive and objective. In order to remedy this defect, this paper proposes a dynamic analysis method of marine environmental protection information dissemination oriented to social network. The dynamic analysis method is introduced into the social marine environmental protection information dissemination to achieve regional dissemination of marine environmental protection information. This method is more efficient and easier to operate. It can effectively spread the expanding operation of social marine environmental protection information, and the amount of marine environmental protection information dissemination on the network unit can be obtained by dynamic analysis. The experiment shows that compared with the previous algorithms, the proposed method has better performance and more prominent expansibility.
Fully protected areas (FPAs) help preserving biodiversity and reversing the global decline of fishery resources. Stocks of the European spiny lobster Palinurus elephas (Fabr. 1787), among the most precious gourmet seafood worldwide, are currently facing a dramatic decline. Previous attempts of recovery based on fishery restrictions or active post-larval restocking in marine reserves provided unsuccessful outcomes. Here we present results of a 5-year restocking program carried through a Collaborative Fishery Research (CFR) project, in three ad-hoc established FPAs replenished using below-legal size wild juveniles. Results showed that Catch per Unit Effort (CPUE) in terms of both density and biomass burst (by ca. 300–700%) just 2 years since FPAs establishment, regardless of location. We also report tangible spillover effects (ca. 30–50% increase in density and biomass CPUE outside the FPAs) by the end of the program. Data from a 15-years lasting monitoring of a pilot FPA established in 1998, where the restocking protocol was conducted and protection kept in force once restocking ceased, demonstrated the persistence in time of restocking’ benefits. We foster that creation of FPAs assisted with local restocking under oriented CFR programs can represent an option for the recovery of European spiny lobster stocks from overfishing.
Studies related to the evaluation of plastics in freshwaters have been increasing in recent years because approximately 80% of plastic items found in the sea are from inland waters. Despite the ecological relevance of these surveys, no information has been available until now about the hazard related to plastic mixtures in freshwaters. To fill this knowledge gap, we carried out a study aimed to assess the environmental risk associated with the “cocktail” of plastics and environmental pollutants adsorbed on their surface in one of the larger European freshwater basins. Plastic debris was collected by a manta trawl along one transect each in four of the Italian subalpine great lakes (Lake Maggiore, Como, Iseo and Garda) and administered to zebra mussels (Dreissena polymorpha), a useful freshwater biological model present in all these lakes. We estimated a plastic density from 4908 MPs/km2 (Lake Iseo) to 272,261 MPs/km2 (Lake Maggiore), while the most common polymers found were polyethylene and polypropylene, with percentages varying between 73% and 100%. A biomarkers suite consisting of 10 different endpoints was performed after 7 days of exposure to investigate the molecular and cellular effects of plastics and related adsorbed pollutants. The main results highlighted a diffuse but different toxicity due to plastics for each lake, and there were significant changes in the antioxidant and detoxifying enzyme activities in Lake Maggiore, Iseo and Garda, an increase in protein carbonylation in L. Como, and a cellular viability decrease of approximately 30% for zebra mussels from L. Iseo and Garda. Despite this variability in the endpoints' responses, the application of the biomarker response index showed a similar environmental hazard due to plastics for all the sampled lakes.
Global warming is heating the Antarctic circumpolar deep water (CDW), which comes into direct contact with the diverse and abundant macrobenthic communities thriving on the continental shelf of the Weddell Sea (WS). A set of 16 current meters deployed along more than 3000 km coastline revealed that tidal currents drive CDW intrusions onto the WS continental shelf and they can increase the temperature near the seabed by ~2.7 °C. The ongoing ocean warming trend may expose macrobenthic assemblages to ambient temperatures >2 °C by the end of the century with dramatic consequences for communities which have evolved during millions of years in near geophysical isolation under rather constant environmental conditions with temperatures <0 °C. These stenothermal communities have long generation times (therefore, reduced opportunity to mutate) and require hundreds of years for adaptation.
Results from 135 benthic stations along the study area showed that macrobenthic communities in the southeastern section of the WS are the most vulnerable to the increase of temperature near the seabed given their high component of sessile organisms. Besides a dramatic marine biodiversity loss, the eventual demise of these communities, which provide habitat structure for a large number of species that can build up >87 g C m−2, will cause the liberation of thousands of tons of carbon to the environment. Macrobenthic communities colonizing the recently opened shelf in the Larsen A and B bays may not have the chance to reach the type of mature assemblage inhabiting the eastern WS shelf. The highest temperatures derived from CDW intrusions were recorded in the Filchner-Ronne region, suggesting that the consequences of the thermal impact could develop faster here than in the rest of the WS. Thus, these macrobenthic communities may show the effects of warming earlier than those thriving in other regions of the WS shelf. Global warming seriously threats the abundant and highly diverse macrobenthic communities of the Antarctic continental shelf.
Phenological shifts, by initiating reproductive events earlier, in response to advanced seasonal warming is one of the most striking effects currently observed in wild populations. For sea turtles, phenological adjustment to warming conditions could be the most effective short-term adaptation option against climate change. We calculated future phenological changes required in seven important loggerhead (Caretta caretta) nesting populations to continue achieving a high hatching success and a sex ratio that lies within current ranges. Considering temperature-mediated phenological changes, we found that most populations (six out of seven) will not be able to keep pace with a warming climate. Under an optimistic climate warming scenario (RCP4.5), these populations will face a climatic debt, that is, a difference between required and expected phenological changes, and warming will substantially reduce hatching success and induce a feminization of hatchlings, which may jeopardize their reproductive sustainability. Our approach offers the possibility to quantify the efficiency of phenological shifts in oviparous reptiles by considering physiological, developmental and phenological processes.
Sea-surface temperature (SST) was one of the first ocean variables to be studied from earth observation satellites. Pioneering images from infrared scanning radiometers revealed the complexity of the surface temperature fields, but these were derived from radiance measurements at orbital heights and included the effects of the intervening atmosphere. Corrections for the effects of the atmosphere to make quantitative estimates of the SST became possible when radiometers with multiple infrared channels were deployed in 1979. At the same time, imaging microwave radiometers with SST capabilities were also flown. Since then, SST has been derived from infrared and microwave radiometers on polar orbiting satellites and from infrared radiometers on geostationary spacecraft. As the performances of satellite radiometers and SST retrieval algorithms improved, accurate, global, high resolution, frequently sampled SST fields became fundamental to many research and operational activities. Here we provide an overview of the physics of the derivation of SST and the history of the development of satellite instruments over half a century. As demonstrated accuracies increased, they stimulated scientific research into the oceans, the coupled ocean-atmosphere system and the climate. We provide brief overviews of the development of some applications, including the feasibility of generating Climate Data Records. We summarize the important role of the Group for High Resolution SST (GHRSST) in providing a forum for scientists and operational practitioners to discuss problems and results, and to help coordinate activities world-wide, including alignment of data formatting and protocols and research. The challenges of burgeoning data volumes, data distribution and analysis have benefited from simultaneous progress in computing power, high capacity storage, and communications over the Internet, so we summarize the development and current capabilities of data archives. We conclude with an outlook of developments anticipated in the next decade or so.
Numerous marine reserves worldwide are losing their ability to protect wild endemic species due to surrounding ecological deterioration caused by coastal landscape artificialization. Such risk of becoming invalid nature reserves is particularly high in China's Bohai Sea coastal zone, a region with rapid urbanization and industrialization. In this study, the ecological quality (EQ) status around Laizhou Bay Ostrea rivularis germplasm reserve (R1), Yellow River Estuary Meretrix meretrix germplasm reserve (R2), and Taoer Estuary Sinonovacula constricta germplasm reserve (R3) was dynamically diagnosed using seven indicators characterizing ecological support and threat from peripheral environments. A series of thresholds indicating EQ and corresponding landscape artificialization intensity (LAI) were determined based on multi-factor clustering analysis and relational regression simulation. The results show that the surroundings of these three reserves were favorable in 1984, insufficient in 2000, and unfavorable in 2015. With an average 7.5 times increase in LAI over the past three decades, the EQ levels around R1-R3 declined significantly and have deviated greatly from their optimal reference status by 2015, which stemmed mainly from intertidal landscape artificialization, such as establishing salt pans, industrial areas and ports after reclaiming wetlands. It was found that R3 > R1 > R2 in terms of overall peripheral ecological degradation, implying that the closer the marine reserve is to the land, the more likely it is to lose its effectiveness. The changes in EQ status and LAI were well indicated by the proportion of natural ecosystems, the distance between seawalls and protected boundaries, and the reserves' enclosed degree by artificial systems, which, as a quick and simple diagnostic approach, can facilitate spatial planning and management practices around marine reserves in the Bohai Sea coastal zone and elsewhere.
Bottom trawling is a common fishing method for harvesting demersal marine resources such as prawns and ground fish species. However, bottom trawling is known to have negative impacts on marine ecosystems and several measures have been suggested to sustainably manage the fishing method including, mapping trawling pressure and restricting its use away from fragile marine ecosystems. In this study, we map spatio-temporal distribution of trawling effort using 8900 trawls obtained from logbook statistical data and consequently evaluate the effectiveness of a Vessel Monitoring System (VMS) and a Prawn Fisheries Management Plan (PFMP) in the Malindi-Ungwana Bay, Kenya. The PFMP and VMS aimed at restricting prawn trawling to areas beyond 3 nm from shoreline since 2010 in order to reduce conflict with artisanal fishers. Results show spatio-temporal adjustments in the distribution of fishing effort and catch rates of prawns following regulatory changes in the bay. Encroachment in no-trawl areas occurred gradually between 2011 and 2017 with some years (2013, 2016) depicting over 50% of fishing effort in the no-trawl areas. Trawling within the restricted zone produced higher catch per unit effort (CPUE) of prawns compared to fishing outside the zone. Introduction of VMS in 2017 led to a significant reduction of fishing effort in no-trawl area of about 80% by 2018. The change in fleet behaviour in the bay after introduction of the VMS, provides important insights on how marine spatial planning and technology could be applied to enhance compliance with fishing area regulations, reduce resource use conflicts and promote sustainable fisheries.
The rate of change on coastlines is accelerating from climate change and coastal development. Coastal flooding is a particularly pressing and increasing problem, which affects hundreds of millions of people and damages trillions of US$ in property. Scientists, practitioners and managers must be able to quickly assess flood risk and identify appropriate adaptation and risk reduction measures often with limited data and tools, particularly in developing countries. To inform these decision-making processes, we identify how sensitive flood risk and adaptation analyses are to changes in the resolution of data and models. We further do these comparisons in the context of assess the benefits of an ecosystem-based approach for risk reduction. There is growing interest in these ecosystem-based approaches as cost effective measures for adaptation and risk reduction. We assess flood risks from tropical cyclones and the flood risk reduction benefits provided by mangroves in Pagbilao (the Philippines). Then, we also compare risks and risk reduction (benefits) using different quality data and models, to identify where to invest in in new modeling and data acquisition to improve decision-making. We find that coastal flood risk valuation improves by using high resolution topography and long time series of data on tropical cyclones, while flood reduction benefits of mangroves are better valued by using consistent databases and models along the whole process rather than investing in single measures.
Metal/metalloid concentrations in water sediment and commercial fishes of Loreto Maritime National Park (MNP), Baja California Sur, Mexico were determined for a comprehensive geochemical study. In-situ physical characteristics (pH, conductivity, redox potential, dissolved oxygen, turbidity) of water clearly indicated the unique oceanographic properties of the Gulf of California. Likewise, the distribution pattern of metals/metalloid in water, sediments and fishes denoted the influences of local geology, longshore currents, upwelling process, natural hydrothermal vents and the 100-year old mining activities of Santa Rosalia region, situated to the north of Loreto. Calculated carcinogenic indices in commercial fish species showed safe human consumption. Thus, the present research validates a comprehensive geochemical study of protected areas upholding the need for continuous monitoring for a better conservation of coastal ecosystems.
The community of species, human institutions, and human activities at a given location have been shaped by historical conditions (both mean and variability) at that location. Anthropogenic climate change is now adding strong trends on top of existing natural variability. These trends elevate the frequency of “surprises”—conditions that are unexpected based on recent history. Here, we show that the frequency of surprising ocean temperatures has increased even faster than expected based on recent temperature trends. Using a simple model of human adaptation, we show that these surprises will increasingly challenge natural modes of adaptation that rely on historical experience. We also show that warming rates are likely to shift natural communities toward generalist species, reducing their productivity and diversity. Our work demonstrates increasing benefits for individuals and institutions from betting that trends will continue, but this strategy represents a radical shift that will be difficult for many to make.