Pollution by marine litter is raising major concerns due to its potential impact on marine biodiversity and, above all, on endangered mega-fauna species, such as cetaceans and sea turtles. The density and distribution of marine litter and mega-fauna have been traditionally monitored through observer-based methods, yet the advent of new technologies has introduced aerial photography as an alternative monitoring method. However, to integrate results produced by different monitoring techniques and consider the photographic method a viable alternative, this ‘new’ methodology must be validated. This study aims to compare observations obtained from the concurrent application of observer-based and photographic methods during aerial surveys. To do so, a Partenavia P-68 aircraft equipped with an RGB sensor was used to monitor the waters off the Spanish Mediterranean coast along 12 transects (941 km). Over 10000 images were collected and checked manually by a photo-interpreter to detect potential targets, which were classified as floating marine macro-litter, mega-fauna and seabirds. The two methods allowed the detection of items from the three categories and proved equally effective for the detection of cetaceans, sea turtles and large fish on the sea surface. However, the photographic method was more effective for floating litter detection and the observer-based method was more effective for seabird detection. These results provide the first validation of the use of aerial photography to monitor floating litter and mega-fauna over the marine surface.
Understanding the factors influencing community acceptance of renewable energy projects such as offshore wind farms is important for achieving a transition to low carbon energy sources. However, to date community acceptance research has concentrated on responses to actual proposals, seeking to explain local objections. ‘Upstream’ research that investigates the ‘place-technology fit’ of a potential renewable energy project before it is proposed is scarce, yet can inform technology deployment by taking local knowledge and preferences into account. We address this gap in a study conducted in Guernsey, Channel Islands. Data was collected using a survey (n = 468) co-designed with island policy makers presenting technical, economic and locational details of a potential offshore wind project. Results show that acceptance of the same project design differed significantly across alternative development locations. Regression analyses compared the roles of personal, context and project-related factors in explaining acceptance for each site. Support for using wind energy for local electricity supply was the most important predictor of acceptance, and this variable mediated the relationship between island energy security and community acceptance. We conclude that place matters for community acceptance and that security and autonomy are co-benefits of local renewable energy projects that deserve further research.
The Common Fisheries Policy in the Mediterranean has been so far based on technical measures that have been relatively stable for a long time, and it did not prevent the efficiency increase in both vessels and gears that have counterbalanced the fleet reduction. The new Multiannual Plan for Demersal fish stocks in the western Mediterranean Sea introduces a fishing effort regime as a new approach to reduce significantly fishing time, allowing stocks to approach MSY in the medium term. However, different approaches to reduce fishing time may have different socio-economic impacts that have to be considered. The reduction of fishing time has to be complemented with selectivity improvements, temporal and permanent closures and local co-management plans to protect both juveniles and spawners. The combination of several measures will soften the need for effort reduction and it will contribute significantly to the sustainability of Mediterranean Fisheries.
To better understand the threats posed by human activities on cetaceans, we compiled published studies and determined where, how, and by whom the research on this subject has been conducted in Brazil. We also determined which cetacean species were mostly investigated in these studies. We gathered the available scientific literature published from 1986 to 2016 that contained search terms in English that depicted major cetacean threats. Then, we developed a collaboration network among the authors' institutions and generated a distribution map of the investigated threats and study areas. From the 1047 compiled publications, we selected 103 studies that precisely addressed cetacean threats. The selected studies were carried out by 82 institutions from 12 countries. Most of these institutions were universities (n = 55), followed by non-governmental organizations (n = 15) and research institutes (n = 12). Among the two cetacean suborders, odontocetes were the most representative, with Sotalia guianensis and Pontoporia blainvillei present in 50 and 38 publications, respectively. For mysticetes, publications on Megaptera novaeangliae (n = 6) and Eubalaena australis (n = 5) were the most common. Among the addressed threats, more than half (54.4%) of the publications focused on pollution, followed by bycatch (19.4%) and vessel traffic (10.7%). Most of the study areas took place in the states of Rio de Janeiro (22.4%), São Paulo (19.7%), and Rio Grande do Sul (12.9%). Six institutions were the most prevalent in the collaboration networks, and their location corresponded to hotspots of cetacean diversity. Our findings may contribute to identifying research priorities and guide the conservation of cetacean species in Brazil.
The dynamics of fish length distribution is a key input for understanding the fish population dynamics and taking informed management decisions on exploited stocks. Nevertheless, in most fisheries, the length of landed fish is still made by hand. As a result, length estimation is precise at fish level, but due to the inherent high costs of manual sampling, the sample size tends to be small. Accordingly, the precision of population-level estimates is often suboptimal and prone to bias when properly stratified sampling programmes are not affordable. Recent applications of artificial intelligence to fisheries science are opening a promising opportunity for the massive sampling of fish catches. Here, we present the results obtained using a deep convolutional network (Mask R-CNN) for unsupervised (i.e. fully automatic) European hake length estimation from images of fish boxes automatically collected at the auction centre. The estimated mean of fish lengths at the box level is accurate; for average lengths ranging 20–40 cm, the root-mean-square deviation was 1.9 cm, and maximum deviation between the estimated and the measured mean body length was 4.0 cm. We discuss the challenges and opportunities that arise with the use of this technology to improve data acquisition in fisheries.
Species conservation, river rehabilitation, stock enhancement, environmental impact assessment and related planning tools require indicators to identify significant impacts but also mitigation success. Since river systems are shaped by disturbances from floods and droughts, typical riverine fish species should have evolved life history traits providing resilience against such disturbances. This study compiled and analyzed resilience traits of European lampreys and fish species to derive a novel sensitivity classification of species to mortality. We assembled life history traits like maximum length, migration type, mortality, fecundity, age at maturity, and generation time of 168 species and created a novel method to weigh and integrate all traits to generate a final sensitivity score from one (low sensitivity) to three (high sensitivity) for each species. Large-bodied, diadromous, rheophilic and lithophilic species such as sturgeons, sea trout, and Atlantic salmon usually appeared to have high sensitivity to additional adult fish mortality, whereas small-bodied, limnophilic and phytophilic species with fast generation cycles were of low sensitivity. The final scoring and classification of 168 European lampreys and fish species according to their sensitivity can be easily regionalized by selecting the most sensitive candidates according to the local species pool. This sensitivity classification has major implications for advancing impact assessment, allowing better targeting of species for conservation measures, benchmarking progress during rehabilitation and enhancing the objective evaluation of the success of restoration projects.
The Rosemary Bank Seamount in the NE Atlantic was designated a Marine Protected Area in 2014 by the Scottish Government. Visual and trawl surveys of the seamount have been undertaken since 2007. Here these data are compiled and analysed to provide an assessment of the communities of demersal fish and benthic invertebrates found there. The fish and benthic invertebrate communities changed markedly with depth. Cluster analysis revealed at least four distinct communities of fish: those on the summit, the mid slope, the lower slope and the deep moat at the base of the seamount. The invertebrate community changed at a depth of 1100 m, where mixed-species sponge aggregations dominated to depths of 1500 m. The seamount is an important site for vulnerable marine ecosystems, most notably the extensive and unusually diverse deep-sea sponge grounds on the lower slope. Other prioritised conservation species and habitats recorded included cold water corals, orange roughy, blue ling, leafscale gulper shark and the Portuguese dogfish. Due to sampling constraints some areas of the seamount still remain unknown. A precautionary approach to protecting the entire seamount would achieve multiple conservation objectives. The data presented here serve as a base-line to assess the impact of management intervention in the future.
A key conservation strategy to protect and manage marine biodiversity is the implementation of marine protected areas (MPAs). The level of protection from human activities offered to biodiversity by MPAs is not uniform but varies according to the type of MPA, as well as by jurisdiction. This diversity in the activities permitted within MPAs means that reporting total area of marine protection does not reflect the level of protection offered to biodiversity. As such, there is the potential for public confusion surrounding what is permitted or prevented within any one MPA. Therefore, it is critical to determine the degree to which the public understands the activities permitted within MPAs, and how this accords with the actual protection offered to biodiversity. To do this, an anonymous survey was conducted to assess the general knowledge about the protection offered by Australian MPAs and, specifically, the activities permitted or prohibited within MPA boundaries. The overwhelming majority of respondents (63%) believe that Australia's MPA system restricts fishing, when this is only true for 25% of the total area protected. While the activities permitted within MPAs vary, the broad pattern remains that respondents overestimate the degree to which MPAs within their state of origin prevent extractive uses. This study suggests that there is a significant gap in the public understanding of marine conservation issues in Australia, highlighting the need for an explicit conversation between policymakers, scientists and the public about whether current levels of marine protection align with public expectations.
“Flow” is a key concept in our era of liquid modernity, across a broad range of ecological, economic, and cultural discourses. In this essay, we examine the material flows integral to naturecultures through the specific case study of Seascale on the Cumbria coast in the UK. Through an analysis of cultural representations, we show the construction of Seascale as a seaside resort in the nineteenth and early twentieth centuries, and the rapid and irrevocable sinking of its cultural value since the commissioning of the nuclear power and reprocessing plant at Sellafield in 1947. By following the “flows” of pleasure, emotion, energy, and waste through Seascale, we explore the legacies of nuclear contamination for coastal communities, within a broader regime of the commodification of nature. This essay emerges from a transdisciplinary research project to investigate the cultural influences and impacts of ecosystem change in coastal environments around the Irish Sea. A collaboration between environmental humanities and ecological sciences, the project sought a materialist intervention in the conceptualization and practice of ecosystem assessment so as to capture and map a more inclusive and multidirectional sense of the flows that are integral to ecosystems, and to move beyond the limitations of dominant models of environmental stewardship. In contrast to the ways in which flow metaphors have been employed in contemporary economic and environmental discourse, the project attempts to analyze the material flows integral to naturecultures through particular places, perspectives, and agencies.
Coastal wetlands have been valued for a variety of ecosystem services including carbon sequestration and long term storage. The carbon sequestered and stored in coastal habitat including mangroves, salt marshes, and seagrass beds is termed as blue carbon. However, these systems are threatened mainly due to sea level rise, limited sediment supply, edge erosion, and anthropogenic influences. These habitats require restoration and conservation to continue providing ecosystem services. The incentive for emission reductions, referred to as carbon offsets, is well established for other ecosystems like forestry and agriculture. Some blue carbon offset methodologies or protocols have been certified by various voluntary carbon markets; however to date, a few wetland restoration carbon offset in the US has been transacted. Thus, the goal of this paper is to discuss the existing carbon market and carbon market methodologies applicable to coastal wetland restoration and conservation in the US. Currently, four wetland carbon offset methodologies have been approved in the carbon market. These methodologies are site and/or project-specific depending on the type of the wetlands, vulnerability to loss, and restoration need. The appropriate carbon stock and Green House Gas (GHG) emission assessment is the basis of determining carbon offsets. Simplification of the existing methodologies and development of new site and project-specific methodologies could potentially help to realize blue carbon offsets in practice. The slowly growing demand for carbon offsets in the carbon market could potentially be fulfilled from the blue carbon pool. While this carbon offset is in the early stages, this review may help the inclusion of carbon offset component in the coastal restoration and conservation projects in United States and potentially across the globe.
These Mapping and estimation of seagrass total above-ground carbon (STAGC) using satellite-based techniques are required to fast-track the achievement of the 2020 agenda on Sustainable Development Goals (SDG) 14th. This attainment is possible as seagrass habitats provide a critical coastal ecosystem for storing blue carbon stock, sediment accumulation, fisheries production and stabilisation of coastal environment. However, seagrasses are generally declining across the globe due to anthropogenic disturbance, resulting in a prolonged growth rate of seagrasses that varies according to the species compositions. Therefore, this study aims at mapping and estimation of seagrass total above-ground carbon (STAGC) using Landsat ETM+ in the coastline of Penang. These satellite images were calibrated with Bottom Reflected Index (BRI) and Depth Invariant Index (DII) to compare the estimate of the STAGC for more accuracy. The leaving radiances of the seagrass were correlated with the corresponding in-situ measurements to predict seagrass carbon. This established relationship with BRI image shown a healthy correlation with STAGB (R2 = 0.992, p ≤ 0.001). Whereas the STAGB versus DII relationship has less accuracy (R2 = 0.955, p ≤ 0.01), adjusted R2 = 0.980 and 0.978 were recorded for both BRI and DII STAGC estimate using the logistic model. Therefore, careful management of blue carbon stock is essential, as this study shall contribute to achieving targets 14.2 and 14.5 of SDG 14th by the United Nations.
Renewed interest in the estimation of spatial and temporal variation in fish traits, such as body size, is a result of computing advances and the development of spatially-explicit management frameworks. However, many attempts to quantify spatial structure or the distribution of traits utilize a priori approaches, which involve pre-designated geographic regions and thus cannot detect unanticipated spatial patterns. We developed a new, model-based method that uses the first derivative of the spatial smoothing term of a generalized additive model to identify spatial zones of variation in fish length-at-age. We use simulation testing to evaluate the method across a variety of synthetic, stratified age and length datasets, and then apply it to survey data for Northeast Pacific sablefish (Anoplopoma fimbria). Simulation testing illustrates the robustness of the method across a variety of scenarios related to spatially or temporally stratified length-at-age data, including strict boundaries, overlapping zones and changes at the extreme of the range. Results indicate that length-at-age for Northeast Pacific sablefish increases with latitude, which is consistent with previous work from the western United States. Model-detected spatial breakpoints corresponded to major oceanographic features, including the northern end of the Southern California Bight and the bifurcation of the North Pacific Current. This method has the potential to improve detection of large-scale patterns in fish growth, and aid in the development of spatiotemporally structured population dynamics models to inform ecosystem-based fisheries management.
The health of the ocean, central to human well-being, has now reached a critical point. Most fish stocks are overexploited, climate change and increased dissolved carbon dioxide are changing ocean chemistry and disrupting species throughout food webs, and the fundamental capacity of the ocean to regulate the climate has been altered. However, key technical, organizational, and conceptual scientific barriers have prevented the identification of policy levers for sustainability and transformative action. Here, we recommend key strategies to address these challenges, including (1) stronger integration of sciences and (2) ocean-observing systems, (3) improved science-policy interfaces, (4) new partnerships supported by (5) a new ocean-climate finance system, and (6) improved ocean literacy and education to modify social norms and behaviors. Adopting these strategies could help establish ocean science as a key foundation of broader sustainability transformations.
Herbivory is an important process in the general structuring of coral reef benthic communities. However, evidence of its ability to control coral reef benthic cyanobacterial mats, which have recently proliferated on reefs worldwide, remains ambivalent. Here, we report that the French Angelfish (Pomacanthus paru), Striped Parrotfish (Scarus iseri), Rock Beauty (Holacanthus tricolor), Ocean Surgeonfish (Acanthurus bahianus), Blue Parrotfish (Scarus coeruleus), and Atlantic Blue Tang (Acanthurus coeruleus) consume benthic cyanobacterial mats on coral reefs in Bonaire, Netherlands. We documented the foraging patterns of P. paru and S. iseri, and found that benthic cyanobacterial mats comprised 36.7% ± 5.8% and 15.0% ± 1.53% (mean ± standard error) of the total bites taken by P. paru and S. iseri respectively. This magnitude of consumption suggests that grazing by reef fishes may represent a potentially important, but previously undocumented, top-down control on benthic cyanobacterial mats on Caribbean reefs.
Conservation management of marine biodiversity depends on biomonitoring of marine habitats, but current approaches are resource‐intensive and require different approaches for different organisms. Environmental DNA (eDNA) extracted from water samples is an efficient and versatile approach to detecting aquatic animals. In the ocean, eDNA composition reflects local fauna at fine spatial scales, but little is known about the effectiveness of eDNA‐based monitoring of marine communities at larger scales. We investigated the potential of eDNA to characterize and distinguish marine communities at large spatial scales by comparing vertebrate species composition among marine habitats in Qatar, the Arabian Gulf (also known as the Persian Gulf), based on eDNA metabarcoding of seawater samples. We conducted species accumulation analyses to estimate how much of the vertebrate diversity we detected. We obtained eDNA sequences from a diverse assemblage of marine vertebrates, spanning 191 taxa in 73 families. These included rare and endangered species and covered 36% of the bony fish genera previously recorded in the gulf. Sites of similar habitat type were also similar in eDNA composition. The species accumulation analyses showed that the number of sample replicates was insufficient for some sampling sites but suggested that a few hundred eDNA samples could potentially capture >90% of the marine vertebrate diversity in the study area. Our results confirm that seawater samples contain habitat‐characteristic molecular signatures and that eDNA monitoring can efficiently cover vertebrate diversity at scales relevant to national and regional conservation and management.
The present study highlights the importance of intertidal seagrass beds as nursery areas for coral reef fish juveniles along four sites (Mtsoubatsou, Sohoa, Boueni, Ngouja) on the western coast of Mayotte Island. The results collected by underwater visual census from November 2012 to January 2013 showed that mean total fish density between adults and juveniles varied significantly at each site, with juveniles always being more abundant in seagrass beds than adults. Of the total fish assemblages sampled in seagrass beds, 73% were juveniles and few adults of large species were observed. Overall, our study highlights the important functional role of intertidal seagrass beds for fish assemblages, as they are the primary habitat for the juveniles of many fish species on Mayotte reefs. Seagrass beds, however, are very vulnerable ecosystems and are decreasing worldwide. Therefore it is of primary importance to protect seagrass beds within the Indo-Pacific.
Since the start of commercial plastics production in the 1940s, global production has rapidly accelerated, doubling approximately every 11 years. Despite this increase and clear evidence of plastics loss into the oceans, including a substantial standing stock, previous research has not detected a temporal trend in plastic particle concentration in the surface ocean. Using a generalized additive statistical model, we examined the longest dataset available on floating plastic debris collected using plankton nets in the western North Atlantic from 1986 through 2015. There was a significant increasing temporal trend in plastic particle concentration that tracked cumulative global plastics production. We estimated an increase of 506,000 tonnes of floating plastic in the ocean in 2010 alone, or 0.2% of global production. Our results suggest that, while loss of plastic particles from the surface ocean undoubtedly occurs, the input exceeds the collective losses.
Marine parks were established to protect the diverse marine ecosystem in Malaysia, and over the years, the islands have attracted an increasing number of tourists. These marine park islands have become not only one of the top ecotourism destinations in Malaysia but an important contributor to the socio-economic growth of the nation. Nonetheless, it is a constant challenge to maintain the marine parks’ natural charm due to negative tourism impacts. Humans’ consumption behaviour has been identified as a driver of climate change. Given that humans’ contribution to the problem is closely related to sustainable behaviour, this study focuses on tourists’ behaviour. With the growing awareness on global environmental challenges, environmental knowledge has often been prescribed as one of the main precursors of tourists’ behaviour, yet few studies have attempted to assess this factor from different dimensions. This paper examines tourists’ environmental knowledge from a multidimensional aspect of factual, conceptual and procedural dimensions to determine its role in influencing attitude and responsible environmental behaviour. A face-to-face survey was conducted among 85 domestic and international marine park tourists, and data were analysed using PLS-SEM method. This preliminary study revealed that environmental knowledge is formatively represented by factual, conceptual and procedural dimensions. Furthermore, results confirmed the linear relationships between knowledge, attitude and behaviour with knowledge as a strong predictor of attitude that leads to higher pro-environmental behaviours, hence highlighting the importance of promoting environmental knowledge among marine park tourists who drives pro-environmental attitude and responsible behaviour to achieve a sustainable ecotourism development.
Globally, conflicts between marine nature conservation and fishery interests are common and increasing, and there is often a glaring lack of dialogue between stakeholders representing these two interests. There is a need for a stronger and enforced coordination between fishing and conservation authorities when establishing marine protected areas for conservation purposes. We propose that an appropriate instrument for such coordination is a broad ecosystem-based marine spatial planning procedure, representing neither nature conservation nor fishery. Strategic environmental assessment for plans and programmes and environmental impact assessment for projects are commonly used tools for assessing the environmental impacts of different human activities, but are seldom used for evaluating the environmental effects of capture fisheries. The diversity of fisheries and the drastic effects of some fisheries on the environment are strong arguments for introducing these procedures as valuable supplements to existing fisheries assessment and management tools and able to provide relevant environmental information for an overall marine spatial planning process. Marine protected areas for nature conservation and for protection of fisheries have different objectives. Therefore, the legal procedure when establishing marine protected areas should depend on whether they are established for nature conservation purposes or as a fisheries resource management tool. Fishing in a marine protected area for conservation purpose should be regulated according to conservation law. Also, we argue that marine protected areas for conservation purposes, in the highest protection category, should primarily be established as fully protected marine national parks and marine reserves.
Despite general and wide-ranging negative effects of coral reef degradation on reef communities, hope might exist for reef-associated predators that use nursery habitats. When reef structural complexity is lost, refuge density declines and prey vulnerability increases. Here, we explore whether the presence of nursery habitats can promote high predator productivity on degraded reefs by mitigating the costs of increased vulnerability in early life, whilst allowing for the benefits of increased food availability in adulthood. We apply size-based ecosystem models of coral reefs with high and low structural complexity to predict fish biomass and productivity in the presence and absence of mangrove nurseries. Our scenarios allow us to elucidate the interacting effects of refuge availability and ontogenetic habitat shifts for fisheries productivity. We find that low complexity, degraded reefs with nurseries can support fisheries productivity that is equal to or greater than that in complex reefs that lack nurseries. We compare and validate model predictions with field data from Belize. Our results should inform reef fisheries management strategies and protected areas now and into the future.