Increases in seawater temperature associated with global climate change are causing the mutualistic relationship between reef-building corals and the symbiotic dinoflagellates (genus Symbiodinium) that reside within their cells to break down. There is consequently an urgent need to develop tools for modeling coral biology in response to environmental shifts, an enterprise that is complicated by the fact that no pristine reefs remain on Earth. This work sought to 1) uncover the environmental factors that contribute most to observed spatio-temporal variation in coral physiology and 2) devise means of detecting anomalous behavior in field corals by analyzing a dataset from the Austral (French Polynesia) and Cook Islands of the South Pacific with a multivariate statistical approach. Upon employing this multi-tiered analytical platform, host genotype was found to be the most significant driver of variation in physiology of the pocilloporid coral colonies sampled across the two archipelagos. Furthermore, those colonies demonstrating the most extensive variation across the seven response variables assessed tended to deviate most significantly from the global mean response calculated across all samples, suggesting that high within-sample physiological variability may be one means of delineating aberrant coral behavior in the absence of data from pristine control reefs.
Mitigating the negative impacts of invasive lionfish (Pterois volitans/milescomplex) is a top priority for marine reef fisheries management, with human removals considered the most viable approach to population control. Control efforts via diver spearfishing removals have annually removed tens of thousands of lionfish throughout their invasive range, but the effectiveness of removal efforts to remove 100% or achieve target lionfish densities in a given reef system has not been fully evaluated. Accounting for detection and removal efficacy is necessary for developing and evaluating lionfish management targets, as population- and community-level effects of lionfish removals may be diminished by undetected lionfish remaining in the system. This study quantified lionfish detection, catchability, and removal efficiency to evaluate the effectiveness of lionfish surveys and removal efforts on northern Gulf of Mexico (nGOM) artificial and natural reefs. Detection was assessed during crepuscular and midday time periods via diver and remotely operated vehicle (ROV) video surveys, with covariates for time of day and survey methodology assessed using generalized linear mixed models. Catchability and removal efficiency were estimated via depletion models based on serial removals via spearfishing on 6 artificial reefs and 9 natural reefs. A priori, we had expected lionfish detection to be higher during crepuscular periods given lionfish in the Caribbean and in their native range have been shown to forage more actively away from reefs then. However, we found lionfish detection was not significantly different between midday and crepuscular periods. Survey methodology affected detection, with 24% fewer lionfish being detected via ROV surveys versus diver surveys at artificial reefs and 72% fewer lionfish detected via ROV surveys at natural reefs. Therefore, density estimates on nGOM natural reefs, which constitute of >99% of the region’s habitat, may be higher than previously reported and problematic for lionfish management. Mean catchability for spearfishing lionfish was 0.88 on artificial reefs and 0.69 on natural reefs standardized for area. Mean removal efficiency for the first removal event was 87% on artificial reefs and 67% on natural reefs, higher than removal efficiency computed for Caribbean reefs (47%). Incomplete detection and <100% removal efficiency, in concert with density-dependent processes, may explain recent findings that sustained lionfish removal efforts had no discernible positive impacts on native reef fish communities.
Micro(nano)plastics, as emerging contaminants, have attracted worldwide attention. Nowadays, the environmental distribution, sources, and analysis methods and technologies of micro(nano)plastics have been well studied and recognized. Nevertheless, the role of micro(nano)plastic particles as vectors for attaching organisms is not fully understood. In this paper, the role of micro(nano)plastics as vectors, and their potential effects on the ecology are introduced. Micro(nano)plastics could 1) accelerate the diffusion of organisms in the environment, which may result in biological invasion; 2) increase the gene exchange between attached biofilm communities, causing the transfer of pathogenic and antibiotic resistance genes; 3) enhance the rate of energy, material and information flow in the environment. Accordingly, the role of microplastics as vectors for organisms should be further evaluated in the future research.
Environmental Impact Assessment (EIA) is an important process for evaluating the effects of development, and to assist decisions to effectively manage potential deep-sea mining (DSM). However, although EIA is a widely used and accepted approach, there has been considerable debate over its effectiveness. In this paper, we summarise some of the key problems raised by previous EIA reviews, as well as examining several EIAs carried out in recent years for DSM, and highlight issues identified by management agencies. Scientific shortcomings are discussed, and recommendations provided on ways to improve performance. These include inadequate baseline data, insufficient detail of the mining operation, insufficient synthesis of data and the ecosystem approach, poor assessment and consideration of uncertainty, inadequate assessment of indirect impacts, inadequate treatment of cumulative impacts, insufficient risk assessment, and consideration of linkages between EIA and other management plans. The focus of the paper is on scientific limitations, but we also consider some aspects of their application to elements of process and policy.
Designation of large expanses of the ocean as Marine Protected Area (MPA) is increasingly advocated and realised. The effectiveness of such MPAs, however, requires improvements to vessel monitoring and enforcement capability. In 2014 commercial fishing was excluded from the Ascension Island Exclusive Economic Zone (EEZ). In 2015, through updated regulations, a licenced fishery re-opened in the northern half of the EEZ while the southern half remained closed. To assess compliance with these closures and regulations, several promising satellite technologies (Satellite Automatic Identification System (S-AIS), Synthetic Aperture Radar (SAR), Vessel Monitoring System (VMS) of two vessels), were trialled alongside at-sea patrols. Use of SAR enabled assessment of ‘dark’ (non-AIS transmitting) vessels, the scope of whose activities are hardest to gauge. The high level of compliance with regulations observed, suggests the MPA may prove effective, yet a need for vigilance remains. Vessels aggregate near the EEZ border and a quarter of vessels tracked across three years exhibited S-AIS transmission gaps and present a heightened compliance risk. Use of remote, rather than local, expertise and infrastructure provide a blue-print and economies of scalefor replicating monitoring across similarly sized MPAs; particularly for large (>~ 25 m) vessels with metallic superstructures conducive to SAR detection. Funding ongoing monitoring in Ascension is challenged by current levels of license uptake, which provides insufficient offsetting revenue. Satellite-derived intelligence, can be used to set risk thresholds and trigger detailed investigations. Planning long-term monitoring must, however, incorporate adequate resources for follow-up, through patrols and correspondence with flag-states and fisheries management organisations.
Spatio-temporal variability of surface geostrophic mesoscale currents in the Balearic Sea (western Mediterranean) is characterized from satellite altimetry in combination with in-situ velocity measurements collected, among others, by drifting buoys, gliders and high-frequency radar. Here, we explore the use of tracking data from living organisms in the Balearic Sea as an alternative way to acquire in-situ velocity measurements. Specifically, we use GPS-tracks of resting Scopoli’s shearwaters Calonectris diomedea, that act as passive drifters, and compare them with satellite-derived velocity patterns. Results suggest that animal-borne GPS data can be used to identify rafting behaviour outside of the breeding colonies and, furthermore, as a proxy to describe local sea surface currents. Four rafting patterns were identified according to the prevailing driving forces responsible for the observed trajectories. We find that 76% of the bird trajectories are associated with the combined effects of slippage and Ekman drift and/or surface drag; 59% are directly driven by the sea surface currents. Shearwaters are therefore likely to be passively transported by these driving forces while resting. The tracks are generally consistent with the mesoscale features observed in satellite data and identified with eddy-tracking software.
Acoustic tagging is typically used to gather data on the spatial ecology of diverse marine taxa, informing questions about spatio-temporal attributes such as residency and home range, but detection data may also reveal unanticipated insights. Many species demonstrate predictable site fidelity, and so a sudden cessation of detections for multiple individuals may be evidence of an atypical event. During 2013 and 2014, we acoustically tagged 47 grey reef sharks (Carcharhinus amblyrhynchos) and 48 silvertip sharks (Carcharhinus albimarginatus) near reefs in the British Indian Ocean Territory (BIOT) Marine Protected Area (MPA). From March 2013 to November 2014 inclusive, tags were ‘lost’, i.e. permanently ceased to be detected within the monitoring area, at an average rate of 2.6 ± 1.0 tags per month. Between 1 and 10 December 2014, detection data suggest the near-simultaneous loss of 15 of the remaining 43 active tagged sharks, a monthly loss rate over five times higher than during the previous 21 months. Between 4 and 14 December of 2014, the BIOT patrol vessel encountered 17 vessels engaged in suspected illegal fishing in the northern BIOT MPA; such sightings averaged one per month during the previous 8 months. Two of these vessels were arrested with a total of 359 sharks on board, of which grey reef and silvertip sharks constituted 47% by number. The unusual and coincident peaks in tag loss and vessel sightings, and the catch composition of the arrested vessels, suggest illegal fishing as a plausible explanation for the unusual pattern in our detection data. A Cox proportional hazards model found that the presence of fishing vessels increased the risk of tag loss by a factor of 6.0 (95% CI 2.6–14.0, p < 0.001). Based on the number of vessels sighted and the average number of sharks on vessels arrested in BIOT during 2014, we conservatively estimate that over 2000 sharks may have been removed during the suspected fishing event. Based on average catch compositions, over 1000 would have been grey reef and silvertip sharks. Assuming a closed population mark-recapture model, over one-third of the locally resident reef sharks may have been removed from the monitoring area. The data suggest that even sporadic fishing events may have a marked impact on local reef shark populations, but also demonstrate the potential of electronic tagging a tool for detecting illegal or otherwise unreported fishing activity.
Offshore mariculture could enable increased seafood production and economic development while alleviating pressure on coastal ecosystems and wild fisheries. In the Caribbean, however, an integrated assessment of the ecological and economic potential for mariculture in the region is lacking. We assess site suitability and develop a spatial bioeconomic model to predict yields and profits for offshore cobia (Rachycentron canadum) mariculture across 30 jurisdictions in the Caribbean. We find that (1) approximately 1.4% of the study area may be technically feasible; (2) the model could avoid conflicts with other uses and sensitive habitats and protected areas; and (3) the model could be economically profitable, with the potential to produce almost half the amount of seafood that is currently harvested from wild fisheries globally. Here, we show that potential farm-scale production and profitability vary across and within countries and that accounting for the foreign investment risk associated with a country will impact estimated farm profitability.
The geometric accuracy of tens of millions of scenes of medium-resolution remote sensing (RS) images collected in the past 45 years has been systematically evaluated for land scenes, but the accuracy of ocean scenes is poorly known due to the lack of ground control points (GCPs). In this study, the locations of offshore platforms are first derived from time-series of Landsat-8 OLI images, and are then used as offshore reference points to systematically assess the geometric performance of RS images covering offshore oil/gas development areas. An inventory of 16,131 offshore platforms at the global scale is established, and then a novel method using the position-invariant characteristic of offshore platforms and the coherent characteristic of the geometric shift among tie-points (i.e. between sensed points from to-be-assessed images and the corresponding OLI-derived reference points) is developed for assessing the geometric accuracy of Landsat and other RS images. The method has been applied to 112,935 Landsat scenes (~1.87% of the entire archive) over oceans. The results indicate an optimal performance of Landsat OLI images (both pre-collection and Collection-1) but a less reliable performance of Landsat TM/ETM+ L1TP images. Approximately 50% of TM L1GS and ETM+ L1GT images have at least 2 pixels of geometric error. The new reference points inventory and the developed method were also applied to many other low-resolution and finer-resolution imagery (e.g. VIIRS Night-fire product, Terra/Aqua MODIS active fire product, ENVISAT ASAR, ALOS-1 PALSAR, Sentinel-1 SAR, Sentinel-2 MSI, the National Agriculture Imagery Program (NAIP) aerial images, and images from several Chinese satellites), and a quantitative description of the geometric accuracy of these sensors is also presented. The findings suggest that the new offshore reference point inventory is probably useful to help establish more robust offshore GCPs for U.S. Geological Survey (USGS) GCP library and further improve the ongoing USGS Global GCP improvement plan and European Space Agency Global Reference Image plan.
Commercial small‐scale fishing in the Mediterranean Sea accounts for more than 80% of the commercial fishing fleet. Commercial small‐scale fishing competes with non‐professional fishing, such as recreational and illegal fishing. Fisheries statistics usually fail to report non‐professional fishing data. The aim of this study was to investigate the competition between fishing categories (commercial, recreational and illegal fishing) and their temporal variability in two future Marine Protected Areas in Tunisia. Over a 2‐year period, 213 small‐scale coastal fisheries landings were monitored. Additional socio‐economic information was collected using direct questionnaires. Results highlighted that: (a) at least 47.91% of non‐professional fishers admitted selling the catch (and so were classified as illegal fishers); (b) illegal and recreational fishing mean catch per fishers per day, represented, respectively, 40% and 20% of commercial fishing; (c) catch rates and species richness for illegal and commercial fishing followed the same temporal patterns at both locations; (d) all fishing categories fished high trophic levels and vulnerable species; and (e) potential economic values of illegal and recreational fishing catch were significantly higher than those of commercial fishing. These findings provide quantitative evidence of competition between illegal and legal (commercial and recreational) fishing in the Mediterranean Sea.
Ocean acidification and warming are known to alter, and in many cases decrease, calcification rates of shell and reef building marine invertebrates. However, to date, there are no datasets on the combined effect of ocean pH and temperature on skeletal mineralization of marine vertebrates, such as fishes. Here, the embryos of an oviparous marine fish, the little skate (Leucoraja erinacea), were developmentally acclimatized to current and increased temperature and CO2 conditions as expected by the year 2100 (15 and 20°C, approx. 400 and 1100 µatm, respectively), in a fully crossed experimental design. Using micro-computed tomography, hydroxyapatite density was estimated in the mineralized portion of the cartilage in jaws, crura, vertebrae, denticles and pectoral fins of juvenile skates. Mineralization increased as a consequence of high CO2 in the cartilage of crura and jaws, while temperature decreased mineralization in the pectoral fins. Mineralization affects stiffness and strength of skeletal elements linearly, with implications for feeding and locomotion performance and efficiency. This study is, to my knowledge, the first to quantify a significant change in mineralization in the skeleton of a fish and shows that changes in temperature and pH of the oceans have complex effects on fish skeletal morphology.
Marine litter is a pollution problem affecting thousands of marine species in all the world's seas and oceans. Marine litter, in particular plastic, has negative impacts on marine wildlife primarily due to ingestion and entanglement. Since most marine mammal species negatively interact with marine litter, a first workshop under the framework of the European Cetacean Society Conference, was held in 2017 to bring together the main experts on the topic of marine mammals and marine litter from academic and research institutes, non-governmental organisations, foundations and International Agreements. The workshop was devoted to defining the impact of marine litter on marine mammals by reviewing current knowledge, methodological advances and new data available on this emerging issue. Some case studies were also presented from European waters, such as seals and cetaceans in the North, Baltic, and Mediterranean Seas. Here, we report the main findings of the workshop, including a discussion on the research needs, the main methodological gaps, an overview of new techniques for detecting the effects of marine litter (including microplastics) on marine mammals and, also, the use of citizen science to drive awareness. The final recommendations aim to establish priority research, to define harmonised methods to detect marine litter and microplastics, enforce networking among institutions and support data sharing. The information gathered will enhance awareness and communication between scientists, young people, citizens, other stakeholders and policy makers, and thereby facilitate better implementation of international directives (e.g., the Marine Strategy Framework Directive) in order to answer the question about the actual status of our oceans and finding solutions.
Cleaning is a fundamental concern of beach managers in many destinations as well as an important requirement in beach quality awards. However, it has been largely neglected in the literature. This paper provides an overview of empirical studies on beach cleaning and analyzes cleaning-related requirements of 11 beach awards that generate controversy in the literature. This study comments on key aspects of beach cleaning, resolves various misconceptions, and provides new perspectives by integrating related topics drawn from a wide range of literature. The arguments based on both the ecological and tourism managerial perspectives are presented, indicating the gaps and proposing research solutions. The paper calls for empirical studies with regard to the efficiency of different cleaning approaches on beaches with varying levels of use intensity and for methodological designs that separate the impacts of mechanical grooming from those of trampling, dune destruction, shore armoring, artificial lighting, among others.
Coastal ecosystems support the livelihoods and wellbeing of millions of people worldwide. However, the marine and terrestrial ecosystem services that coastal ecosystems provide are particularly vulnerable to global environmental change, as are the coastal communities who directly depend on them. To navigate these changes and ensure the wellbeing of coastal communities, policy-makers must know which coastal ecosystem services matter to whom, and why. Yet, in developing coastal settings, capturing people’s perceptions of the importance of ecosystem services is challenging for several reasons. Firstly, coastal ecosystem services encompass both terrestrial and marine services across multiple categories (i.e. provisioning, supporting, and cultural) that are difficult to value together. Secondly, widely used monetary valuation techniques are often inappropriate because of culturally specific attributions of value, and the intangible nature of key cultural ecosystem services. Thirdly, people within communities may hold different ecosystem services values. In this paper, we examine how people ascribe and explain the importance of a range of marine and terrestrial ecosystem services in three coastal communities in Papua New Guinea. We use a mixed-methods approach that combines a non-monetary ranking and rating assessment of multiple ecosystem services, with a socio-economic survey (N = 139) and qualitative explanations of why ecosystem services matter. We find that people uniformly ascribe the most importance to marine and terrestrial provisioning services that directly support their livelihoods and material wellbeing. However, within communities, gender, wealth, and years of formal schooling do shape some differences in how people rate ecosystem services. In addition, although cultural ecosystem services were often rated lower, people emphasized that they ranked provisioning services highly, in part, because of their contribution to cultural values like bequest. People also expressed concern about extractive ecosystem services, like fuelwood, that were perceived to be destructive, and were rated low. We contend that comprehensive ecosystem services assessments that include narratives can capture the broad importance of a range of ecosystem services, alongside relational values and normative judgements. This exploratory approach is a useful step towards understanding the complexities of ecosystem services in developing coastal settings.
Ecological trade-offs due to different perturbations are here quantified by comparing direct impacts and net effects using fishing pressures on marine ecosystems as controlled perturbations. Results highlight that trade-offs emerge in majority of cases when evaluated through multispecies models and are independent from model complexity. Trade-offs showed a dome-shaped relationship with direct impact thus supporting the theory of positive effects of intermediate levels of disturbance. Moreover, trade-off intensity resulted to be related to the capability of the system to react to perturbation, i.e., to ecosystem resilience. Overall the work shows the benefit of complex system analysis that permits the emerging ecological trade-offs which are neglected in simpler single species analyses.
The South Pacific Regional Fisheries Management Organisation (SPRFMO) Convention includes specific provisions to protect vulnerable marine ecosystems (VMEs). The SPRFMO Commission has determined that the interim measures put in place to protect VMEs should be replaced by an improved system of fishable and closed areas. We used the conservation planning tool Zonation to examine the utility of a decision-support tool to develop spatial management options that balance the protection of VMEs with utilisation of high value areas for fishing. Input data included: habitat suitability maps for VME indicator taxa, and uncertainties associated with these model predictions, for an area of the high seas around New Zealand; naturalness condition, represented by two proxy variables using New Zealand trawl effort data; and value to the New Zealand fishery using trawl catch data for two gear types and three time-periods. Running scenario analyses with these data allowed for an understanding of the effect of varying the input data on the spatial prioritisation of areas for VME conservation. The analyses also allowed for the cost to fishing to be determined, in terms of the amount of the trawl catch footprint (normalised to the catch) lost if high priority areas for VME indicator taxa are protected. In most scenarios, the cost to fishing was low given the relatively high proportion of suitable habitat for VME indicator taxa that could be protected. The main outcome of the present study is a demonstration of the practical utility of using available data, including modelled data, and the Zonation decision-support tool to develop future options for the spatial management of the SPRFMO area. Suggestions are also made for improvements in input data for future analyses.
Bangladesh is host to a major cetacean habitat. The country declared its first marine protected area, namely, the Swatch-of-No-Ground Marine Protected Area, for conservation of some species of dolphins, porpoises, whales and sharks. However, this declaration has not been supported with an effective and robust legal, policy and institutional framework. Against this backdrop, this article critically examines the existing legal and institutional framework for management of this marine protected area. A study on the existing legal framework shows the absence of a robust national legal system for prevention of marine pollution and protection of marine biodiversity. This lack of national legal framework will have a significant impact on the future success of the Marine Protected Area. Moreover, an analysis of the relevant national institutions shows that they are not fully capable of enforcing the law and policy in the marine protected area. Through this analysis, this paper proposes that preparation of a management plan, provision of adequate resources to the relevant agencies, ensuring interagency cooperation, engagement of stakeholders and implementation of international marine environmental law are crucial for the future success of this marine protected area.
We are currently in what might be termed a “third phase” of ocean enclosures around the world. This phase has involved an unprecedented intensity of map-making that supports an emerging regime of ocean governance where resources are geocoded, multiple and disparate marine uses are weighed against each other, spatial tradeoffs are made, and exclusive rights to spaces and resources are established. The discourse and practice of marine spatial planning inform the contours of this emerging regime. This paper examines the infrastructure of marine spatial planning via two ocean data portals recently created to support marine spatial planning on the East Coast of the United States. Applying theories of ontological politics, critical cartography, and a critical conceptualization of “care,” we examine portal performances in order to link their organization and imaging practices with the ideological and ontological work these infrastructures do, particularly in relation to environmental and human community actors. We further examine how ocean ontologies may be made durable through portal use and repetition, but also how such performances can “slip,” thereby creating openings for enacting marine spatial planning differently. Our analysis reveals how portal infrastructures assemble, edit, and visualize data, and how it matters to the success of particular performances of marine spatial planning.
Quality of environmental impact assessments (EIAs) has been criticized, in part due to a lack of accounting in these tools for differing spatial and temporal scales inherent in ecological data. In the United States, leases of outer continental shelf blocks for offshore wind projects and their construction and operation plans require EIAs in accordance with the National Environmental Policy Act of 1969 and the 1978 Council on Environmental QualityRegulations for Implementing the Procedural Provisions of the National Environmental Policy Act. This study evaluated consideration of spatiotemporal scales of stressors, receptors (specifically cetaceans), and effects in eight federal offshore wind energy EIAs against 26 criteria extracted from federal regulations. The criteria analysis determined that EIAs do not consistently or comprehensively address spatiotemporal scales with respect to federal requirements. Deficiencies in addressing spatiotemporal scales may result from imprecise regulations, intent to simplify encyclopedic documents, or lack of data resulting in incomplete assessments, inappropriate mitigation actions, and projects delays. Recommendations to improve compliance with federal regulations include making federal guidance binding, focusing on non-trivial impacts of species, tiering information, and incorporating outcomes of marine spatial planning.