Microplastics are ubiquitous throughout the oceans, yet few studies have documented their occurrence in marine organisms associated with coral reefs. Four genera of adult fish were sampled (Myripristis spp., Siganusspp., Epinephelus merra and Cheilopogon simus) from different trophic guilds around the tropical island of Moorea, French Polynesia. Digestive tracts from 133 adult fish were surveyed and microplastics were found in 28 tracts (21%). Abundance of ingested microplastic pieces per individual fish varied from 1 to 3 pieces, with an average of 1.25 ± 0.13 ingested microplastic pieces. Microplastics size ranged from 0.031 to 2.44 mm and 70% of microplastics did not exceed 0.3 mm in size. Overall, this study shows that the number and size of microplastic ingested per trophic groups are independent of trophic guild. Additional studies are needed to sample in other tropical regions in order to have a better assessment of microplastic occurrence in coral reefs.
Nowadays, there is an increased awareness on the threat that marine littermay pose to the marine environment. This review describes the major concerns related to plastic pollution, namely in terms of toxicity of different types and sizes of nanoplastics (particles smaller than 100 nm) to marine organisms, either producers or consumers. The available data show that nanoplastics may affect negatively organisms from different phyla with reported effects ranging from alterations in reproduction to lethality. Nevertheless, no information regarding marine vertebrates (e.g., fish) was found. Data show a high potential for bioaccumulation/biomagnification along marine food chains, since they can easily be retained inside organisms. The lack of standardized methodology for nanoplastics detection and the poor or inexistent legislation makes nanoplastics an environmental challenge.
Although Taiwan has taken conservation measures for coastal and offshore fishery resources in recent years, the effectiveness of resources rebuilding is unclear. Many initiatives, such as marine protected areas (MPAs), are frequently opposed by fishermen. This research reviewed management measures and interviewed 313 fishermen by purposive stratification and snowball sampling. Data were analyzed by fishery, age, and vessel size to address the attitudes and perceptions of fishermen toward twelve fisheries management measures. Descriptive statistics, as well as chi-squared tests and independent t-tests, were used for basic analysis and differences comparison between groups. The results showed that illegal fishing vesselsfrom China (71%), overfishing (69.5%), and ghost fishing (64%) are considered as major threats to Taiwan marine resources. The measures from voyage data recorders, larval anchovy, precious coral, and shark management result in higher satisfaction because of strict monitoring. The satisfaction measures for three net-type measures, i.e., trawler area closure, torch-light limitation, and gillnet limitation, were low. Line-type and small-scale vessel fishermen are more concerned with “small mesh size” and “ghost fishing”. Net-type, large-scale vessels and young fishermen were concerned about “climate change” and “inappropriate measures”. In conclusion, the priorities are to (1) establish a comprehensive scientific research framework; (2) strengthen enforcement to ensure resources rebuilding, especially for large-scale net fisheries; (3) promote public awareness and build communication between stakeholders to obtain support; and (4) communicate among policymakers and fishermen to increase mutual understanding.
Converting assemblages of marine protected areas (MPAs) into functional MPA networks requires political will, multidisciplinary information, coordinated action and time. We developed a new framework to assist planning environmental representativity in a network across the marine space of Portugal, responding to a political commitment to protect 14% of its area by 2020. An aggregate conservation value was estimated for each of the 27 habitats identified, from intertidal waters to the deep sea. This value was based on expert-judgment scoring for environmental properties and features relevant for conservation, chosen to reflect the strategic objectives of the network, thus providing an objective link between conservation commitments and habitat representativity in space. Additionally, habitats' vulnerability to existing anthropogenic pressures and sensitivity to climate change were also scored. The area coverage of each habitat in Portugal and within existing MPAs (regionally and nationally) was assigned to a scale of five orders of magnitude (from <0.01% to >10%) to assess rarity and existing representation. Aggregate conservation value per habitat was negatively correlated with area coverage, positively correlated with vulnerability and was not correlated with sensitivity. The proposed framework offers a multi-dimensional support tool for MPA network development, in particular regarding the prioritization of new habitats to protect, when the goal is to achieve specific targets while ensuring representativity across large areas and complex habitat mosaics. It requires less information and computation effort in comparison to more quantitative approaches, while still providing an objective instrument to scrutinize progress on the implementation of politically set conservation targets.
A leading argument for no-take marine protected area (marine reserve) establishment is their contribution to the conservation of biodiversity, but the impacts of reserves on ecosystem functioning have seldom been quantified. This is unusual given the value of services provided by ocean ecosystems to human well-being. While no single index can describe ecosystem function, a set of life-history attributes possessed by taxa can be used to infer differences in ecosystem function across space and time. In this study, we use biological trait analysis to determine whether the attributes of invertebrate taxa differ between inside of six no-take marine reserves and outside, in fished areas in the Central Philippines. Using permutational multivariate analyses, we found that the composition of traits and taxa were significantly different between reserve and non-reserve areas. Habitat use, morphology and mobility traits were the biggest contributors to dissimilarity, indicating that reserves can have community-wide effects that change the functional composition of invertebrate assemblages. Notably, traits associated with coral habitat use, bearing a shell, lacking mobility and filter feeding are the most important traits associated with differences in community structure between reserve and non-reserve areas. At the taxa composition level, small shrimps, three families of bivalve, two families of burrowing snails and brittle stars are the most important contributors to differences in taxonomic community composition. The addition of organismal attributes to traditional taxa composition approaches provides richer insight into how ecosystems respond to protection and has the potential to inform practitioners on conserving for ecosystem traits.
The dolphin is an animal that we are interested in researching and have established various relationships with for a very long time. They are known as one of the smartest animals, and diverse research about their cognitive ability has been reported from many different viewpoints. In particular, their visual perception and characteristics of visibility of panels on which some figures are printed have been studied, but as yet their perception of information device screens has not. We attempted to reveal their ability to perceive information through pictures displayed on a screen in order to utilize information devices effectively for research and communication in the future. We displayed two kinds of target pictures on the screen to a female bottlenose dolphin (Tursiops truncatus) and assigned a particular action of the subject to each picture. We switched the pictures in front of her and recorded her reactions as a success rate and how she would act in case of failure. Ultimately, she proved that she understands the concept of information devices, and it is expected to be further established that dolphins perceive dynamic information more easily than static information.
Shellfish profession is jeopardized by water quality problem that concerns inlet, with the need to protect the animals from pathogens contaminations, and effluents potentially harmful for the environment with the presence of pathogens, nutrients or organic matter. In this study, ultrafiltration was tested to answer these issues. The objective of the work was two-fold: (i) treat a real effluent from an oyster breeding, the pilot had to continuously face a water containing organic matter and pathogens and (ii) use ultrafiltered water to feed an oyster spat. The process was proved to be efficient in terms of total suspended solids (TSS) and bacterial retention, and especially for Vibrio bacteria, some of whom are potentially harmful for shells. The sustainability of the process facing this pollution was demonstrated and thus for different filtration conditions. Indeed, backwashes and air-backwashes performed were efficient enough to control the fouling generated, so a chemical cleaning was necessary about every 12 h. Water quality parameters, physico-chemical and bacterial, of ultrafiltered effluents were similar to the one obtained with a classical seawater used to feed oyster spats. Ultrafiltration was efficient to treat an effluent from oyster farm and produce water allowing the grown of juveniles. This process could be a solution to reuse effluents in shellfish farms.
Effective stakeholder participation is increasingly seen as an essential part of improving marine and coastal management. Coastal partnerships are a well-established informal method for enabling stakeholder participation in coastal management. However, how well they perform this role has been little explored. The North West Coastal Forum is a UK regional coastal partnership, interacting with stakeholders from across local, regional, national and international spatial scales. At the time of this research, the Forum had been in place for 14 years and, with its excellent record keeping, provided a valuable case study of the effectiveness of coastal partnerships to engage with and represent stakeholders over time. This study both analysed Forum records and conducted an electronic survey of Forum members. The diversity of stakeholders that participate in the Forum and how that has changed over time was examined. Forum members’ perception of the purpose of the Forum and their level of satisfaction with Forum performance was also investigated. In addition, we explored members’ values and how they aligned with the organisations they were representing. Results indicated that, whilst many sectors have been represented on the Management Board and at Forum events, there are some which dominated, particularly Local Authorities, and others, such as extractive industries, which were under-represented. Overall, survey respondents’ perceptions of the Forum purpose aligned with its stated purpose very well. Respondents were also supportive of the performance of the Forum: 56% considered the Forum to have delivered on initial expectations “well” or “very well” and only 4% “poorly”. Respondents’ personal values tended towards pro-environmentalism and were broadly in line with the perceived values of their own host organisations, suggesting that stakeholder representatives can be effective conduits. This study indicates that coastal partnerships can be viewed by stakeholders as an effective means for facilitating stakeholder engagement. As such, coastal management efforts should encourage the development and ideally provide long term support for coastal partnership initiatives. However, this study also suggests that active recruitment is needed to encourage a full range of stakeholders to participate and thus enable coastal partnerships to more fully contribute to integrated coastal zone management.
Marine fisheries plays an important role in ensuring food security and providing livelihoods in South Africa, as in many other developing coastal States. Transnational fisheries crime seriously undermines these goals. Drawing on empirical research this contribution highlights the complexity of law enforcement at the interface between low-level poaching and organised crime in the small-scale fisheries sector with reference to a South African case study. Specifically, this article examines the relationship between a fisheries-crime law enforcement approach and the envisaged management approach of the South African Small-Scale Fisheries Policy.
In this study, we estimate the shoreline retreat, the vulnerability and the erosion rates of an open beach-dune system under projected sea level rise (SLR) and the action of wind-waves (separately and in combination). The methodology is based on the combination of two state-of-the-art numerical models (XBeach and Q2D-morfo) applied in a probabilistic framework and it is implemented in an open sandy beach in Menorca Island (Western Mediterranean). We compute the shoreline response to SLR during the 21st century and we assess the changing impacts of storm waves on the aerial beach-dune system. Results demonstrate the relevant role that the beach backshore features, such as the berm, play as coastal defense, reducing the shoreline retreat and dune vulnerability rates in the near-term (a few decades ahead) and highlighting the importance of simulating the beach morphodynamic processes in coastal impacts assessments. Our findings point at SLR as the major driver of the projected impacts over the beach-dune system, leading to an increase of ∼25% of the volume eroded due to storm waves by the end of the century with respect to present-day conditions.
An efficient connectivity-based method for multi-objective optimization applicable to the design of marine protected area networks is described. Multi-objective network optimization highlighted previously unreported step changes in the structure of optimal subnetworks for protection associated with minimal changes in cost or benefit functions. This emphasizes the desirability of performing a full, unconstrained, multi-objective optimization for marine spatial planning. Brute force methods, examining all possible combinations of protected and unprotected sites for a network of sites, are impractical for all but the smallest networks as the number of possible networks grows as 2m, where mis the number of sites within the network. A metaheuristic method based around Markov Chain Monte Carlo methods is described which searches for the set of Pareto optimal networks (or a good approximation thereto) given two separate objective functions, for example for network quality or effectiveness, population persistence, or cost of protection. The optimization and search methods are independent of the choice of objective functions and can be easily extended to more than two functions. The speed, accuracy and convergence of the method under a range of network configurations are tested with model networks based on an extension of random geometric graphs. Examination of two real-world marine networks, one designated for the protection of the stony coral Lophelia pertusa, the other a hypothetical man-made network of oil and gas installations to protect hard substrate ecosystems, demonstrates the power of the method in finding multi-objective optimal solutions for networks of up to 100 sites. Results using network average shortest path as a proxy for population resilience and gene flow within the network supports the use of a conservation strategy based around highly connected clusters of sites.
The trade in coral reef fishes for aquariums encompasses over 1,800 species from over 40 exporting countries, yet the population status for most traded species is unknown and unevaluated. At the same time, these coral reef fishes face a growing number of threats and often occur in jurisdictions with limited management capacity and data. In response, we assess vulnerability to overfishing for 72 coral reef fishes popular in the aquarium trade for the United States – the top importer – from the top exporting countries (Indonesia and the Philippines). We use a data-limited assessment approach: productivity susceptibility analysis (PSA). PSA estimates relative vulnerability of species by assessing their biological productivity and susceptibility to overfishing. The most and least vulnerable stocks were differentiated by attributes related to the reproductive biology (e.g., breeding strategy, recruitment pattern, and fecundity), appropriateness, for an average home aquarium, ease of capture (e.g., schooling and aggregation), and rates of natural mortality. Our analysis identifies several of the most and least vulnerable species popular in the aquarium fish trade. The species that ranked as least vulnerable to overcollection were Gobiodon okinawae, Nemateleotris magnifica, Gobiodon acicularis, Salarias fasciatus, Ptereleotris zebra, Gobiodon citrinus, Pseudocheilinus hexataenia, Chaetodon lunula, Nemateleotris decora, and Halichoeres chrysus. In contrast, the ten most vulnerable species were Chromileptes altivelis, Plectorhinchus chaetodonoides, Pterapogon kauderni, Premnas biaculeatus, Echidna nebulosa, Centropyge bicolor, Zebrasoma veliferum, Pomacanthus semicirculatus, Zebrasoma scopas, and Thalassoma lunare. In a data-limited context, we suggest how these vulnerability rankings can help guide future efforts for reducing vulnerability risk. In particular, species that are relatively high-vulnerability are prime targets for research and aquaculture efforts, increased monitoring of collection and exports, species-specific stock assessments, and voluntary reductions by retailers and consumers to avoid overexploitation.
In just four decades, hundreds of hydrothermal vent fields have been discovered, widely distributed along tectonic plate boundaries on the ocean floor. Vent invertebrate biomass reaching up to tens of kilograms per square meter has attracted attention as a potential contributor to the organic carbon pool available in the resource-limited deep sea. But the rate of chemosynthetic production of organic carbon at deep-sea hydrothermal vents is highly variable and still poorly constrained. Despite the advent of molecular techniques and in situ sensing technologies, the factors that control the capacity of vent communities to exploit the available chemical energy resources remain largely unknown. Here, we review key drivers of hydrothermal ecosystem productivity, including (a) the diverse mechanisms governing energy transfer among biotic and abiotic processes; (b) the tight linkages among these processes; and (c) the nature and extent of spatial and temporal diversity within a variety of geological settings; and (d) the influence of these and other factors on the turnover of microbial primary producers, including those associated with megafauna. This review proposes a revised consideration of the pathways leading to the biological conversion of inorganic energy sources into biomass in different hydrothermal habitats on the seafloor. We propose a conceptual model that departs from the canonical conservative mixing-continuum paradigm by distinguishing low-temperature diffuse flows (LT-diffuse flows) derived from seawater and high-temperature fluids (HT-diffuse flow) derived from end-member fluids. We further discuss the potential for sustained organic matter production at vent-field scale, accounting for the natural instability of hydrothermal ecosystems, from the climax vent communities of exceptional productivity to the long-term lower-activity assemblages. The parameterization of such a model crucially needs assessment of in situ rates and of the largely unrecognized natural variability on relevant temporal scales. Beyond the diversity of hydrothermal settings, the depth range and water mass distribution over oceanic ridge crests, volcanic arcs and back-arc systems are expected to significantly influence biomass production rates. A particular challenge is to develop observing strategies that will account for the full range of environmental variables while attempting to derive global or regional estimates.
Climate change is outpacing existing rates of evolution and adaptation for many marine organisms. Human societies are pushing hard to find new solutions to save and protect marine ecosystems, generating research on manipulating genetics of wild organisms for the goal of conservation. This – “assisted evolution” – raises challenging ethical questions because the intention is not to revert to a previous status quo, but to modify a community so that it survives better in the conditions we have created. In so doing, our role changes toward “designers” of nature, which requires a rethinking of what is natural, and whether altering or influencing genetics of wild organisms changes the way we conceptualize nature. Assisted evolution could also perpetuate damaging habits and dispositions, such as commodification and technological intervention, which have caused the harm in the first place. Even if we feel morally obliged to repair ecosystems, we still risk further havoc if our attempts to fix our damage are affected by ignorance. Still, from an ethical point of view, we offer cautious support for research on assisted evolution tools. However, we must be clear that we are using these approaches for our own benefit, and should only proceed when they are adequately understood and other options are exhausted. In many cases, we should instead focus our efforts on protecting what we can, minimizing future damage, and understanding future changes. Either way, we need stronger ethical regulations on applying assisted evolution techniques in marine conservation so that there is sufficient deliberation before we use these tools.
Coastal communities, indigenous peoples, and small-scale fishers rely on the ocean for livelihoods, for subsistence, for wellbeing and for cultural continuity. Thus, understanding the human dimensions of the world’s peopled seas and coasts is fundamental to evidence-based decision-making across marine policy realms, including marine conservation, marine spatial planning, fisheries management, the blue economy and climate adaptation. This perspective article contends that the marine social sciences must inform the pursuit of sustainable oceans. To this end, the article introduces this burgeoning field and briefly reviews the insights that social science can offer to guide ocean and coastal policy and management. The upcoming United Nations Decade of Ocean Science for Sustainable Development (2021–2030) provides a tremendous opportunity to build on the current interest, need for and momentum in the marine social sciences. We will be missing the boat if the marine social sciences do not form an integral and substantial part of the mandate and investments of this global ocean science for sustainability initiative.
Forecasts of marine environmental and ecosystem conditions are now possible at a range of time scales, from nowcasts to forecasts over seasonal and longer time frames. Delivery of these products offers resource managers and users relevant insight into ecosystem patterns and future conditions to support decisions these stakeholders face associated with a range of objectives. The pace of progress in forecast development is so rapid that the scientific community may not be considering fully the impacts on stakeholders and their incentives. Delivery of information, particularly about future conditions and the uncertainties associated with it, involves a range of judgements, or “ethical” considerations, including treatment of forecast failure, inequity in stakeholder response options, and winners and losers in commercial markets. Here, we explore these often unanticipated considerations via a set of case studies spanning commercial fishing, recreational fishing, aquaculture, and conservation applications. We suggest that consideration of ethical issues by scientists and their research partners is needed to maintain scientific integrity and fairness to end users. Based on these case studies and our experience, we suggest a set of ten principles that might be considered by developers and users of ecological forecasts to avoid these ethical pitfalls. Overall, an interdisciplinary approach, and co-production with end users will provide insurance against many unanticipated consequences.
Social perception is key to the success of biodiversity conservation policies. A range of socioeconomic guilds can be affected by marine conservation. Among them, fishers are the ones most likely affected and affecting marine protected areas (MPAs). Here, we assessed the perceptions on the sustainability of a type of multiple-use MPA, Fishing Reserves (FRs), by a broad spectrum of national (n = 16) and local (n = 14) stakeholder organisations pertaining to six socioeconomic sectors via two online surveys in Spain. We compared organisational perception by stakeholder organisations, and specifically by the fishing guild, with official fishing statistics for six FRs between 1998 and 2016 using a Before-After-Impact (BAI) research design. Spanish FRs were regarded as sustainable marine management tools by most marine and coastal stakeholders, with environmental effects perceived to be more positive than social and economic ones, respectively. However, primary sector organisations stated null or negative effect of FR designation on their activities, although official statistics showed a moderate to large increase in a number of professional fishing-related variables, including number of boats and crews, after designation of most FRs. Spatial scale did not affect stakeholder perception of local socioeconomic effects of FRs, although some relevant local socioeconomic variables that were thought to vary most after FR designation differed across scales. Some suggested managerial improvements for increased socioeconomic sustainability of Spanish FRs by the professional fishing guild included: greater stakeholder engagement in FR designation and operation, more flexible fishing regulations and stricter control of recreational fishing.
The dramatic decline of European eel (Anguilla anguilla) populations over recent decades has attracted considerable attention and concern. Furthermore, little is known about the sensitivity of the early stages of eels to projected future environmental change. Here, we investigated, for the first time, the potential combined effects of ocean warming (OW; Δ + 4°C; 18°C) and acidification (OA; Δ − 0.4 pH units) on the survival and migratory behaviour of A. anguilla glass eels, namely their preference towards riverine cues (freshwater and geosmin). Recently arrived individuals were exposed to isolated and combined OW and OA conditions for 100 days, adjusting for the salinity gradients associated with upstream migration. A two-choice test was used to investigate migratory activity and shifts in preference towards freshwater environments. While OW decreased survival and increased migratory activity, OA appears to hinder migratory response, reducing the preference for riverine cues. Our results suggest that future conditions could potentially favour an early settlement of glass eels, reducing the proportion of fully migratory individuals. Further research into the effects of climate change on eel migration and habitat selection is needed to implement efficient conservation plans for this critically endangered species.
Understanding the social dimensions of marine and coastal conservation is considered integral to better inform governance and management actions. Perceptions are recognized as a way to understand these dimensions, which can evidence limitations of current efforts, while facilitating more informed policy-making and provide a basis for more robust management actions. Following a qualitative and case study approach, this paper utilizes stakeholder interviews to explore the perceptions on marine ecosystems and current management actions that include marine protected areas (MPAs) in the Central American country of Guatemala. Results identify similarities and contrasts in the perception of marine conservation and MPAs, where weak local governments and limited community participation in the decision-making process can be considered the underlying problems. Recommendations are made which can capitalize upon multi-level improvements that need to integrate all stakeholder groups. Improvements should also consider the regional setting and must reflect Guatemala’s historical and social context. This paper highlights that stakeholder perceptions need a central role to further improve the quality of governance in coastal Guatemala. Recommendations can further assist other developing countries facing similar challenges.
Central to appropriate wildlife management is an effective monitoring program. Monitoring wildlife in urban environments offers unique challenges in the form of barriers, prohibited access and crime. It also, however, provides a unique opportunity to enlist residential communities in collecting data on distribution of a number of species. Opportunistic sightings data has its flaws, including the lack of data on species absences, and unequal sampling effort. Yet these data may still provide reliable information on the distribution of species and complement localized, hypothesis driven research. Where possible opportunistic sightings data should be validated against traditional methods to determine their value for long term monitoring programmes. We use Maxent to model citizen-reported sightings to determine whether sightings of Cape clawless otters (Aonyx capensis) can complement standardized river occupancy surveys to monitor an elusive, widely distributed species living within a fragmented urban/natural matrix. The drivers of otter presence and the predicted distribution of otters modelled from citizen sightings mirrored that provided by previously published results based on occupancy models in the same system, and highlighted further areas of suitable otter habitat and routes for dispersal. Involving citizens in the monitoring of the urban otter population complemented standardized occupancy surveys and provided additional benefits. In addition to alleviating the pressure on local authorities to allocate resources to routine monitoring, citizen involvement provides an opportunity to gather supplementary data on behaviour and/or threats to the species; shed light on the potential dispersal routes, and promote awareness and encourage coexistence with urban adapted wildlife.