Deep-sea tailings disposal (DSTD) and its shallow water counterpart, submarine tailings disposal (STD), are practiced in many areas of the world, whereby mining industries discharge processed mud- and rock-waste slurries (tailings) directly into the marine environment. Pipeline discharges and other land-based sources of marine pollution fall beyond the regulatory scope of the London Convention and the London Protocols (LC/LP). However, guidelines have been developed in Papua New Guinea (PNG) to improve tailings waste management frameworks in which mining companies can operate. DSTD can impact ocean ecosystems in addition to other sources of stress, such as from fishing, pollution, energy extraction, tourism, eutrophication, climate change and, potentially in the future, from deep-seabed mining. Environmental management of DSTD may be most effective when placed in a broader context, drawing expertise, data and lessons from multiple sectors (academia, government, society, industry, and regulators) and engaging with international deep-ocean observing programs, databases and stewardship consortia. Here, the challenges associated with DSTD are identified, along with possible solutions, based on the results of a number of robust scientific studies. Also highlighted are the key issues, trends of improved practice and techniques that could be used if considering DSTD (such as increased precaution if considering submarine canyon locations), likely cumulative impacts, and research needed to address current knowledge gaps.
Overfishing is one of the persistent environmental challenges of our time. Almost one third of the world’s assessed commercially exploited marine fish stocks are considered overfished. This report, co-authored by researchers at the Environmental Defense Fund and the Nicholas Institute for Environmental Policy Solutions, introduces the idea of a blended capital approach to fill the all-too-common finance gap that may hamper recovery of many fisheries. The report describes the categories of investment required to attain fisheries sustainability at each stage of the recovery process, identifies where within this framework there is likely to be the biggest funding gap, and suggests possible approaches for philanthropic and public capital to leverage private capital to help fill the gap. The authors suggest that if we are able to increase the types and amount of capital available to fund fisheries reform—and utilize one to leverage the others where needed—blended capital approaches may send clearer signals to decision makers that change is not only possible but in everyone’s best interests. In aggregate, such signals could help move us closer to advancing a suite of Sustainable Development Goals that would result in thriving, resilient oceans that support more fish, feed more people, and improve prosperity.
The performance of a combined catch quota and habitat credit system was explored to manage the sustainable exploitation of a mix of demersal fish species and reduce the benthic impacts of bottom trawl fisheries using a dynamic state variable model approach. The model was parameterised for the Eastern English Channel demersal mixed fishery using otter trawls or dredges. Target species differed in their association with habitat types. Restricting catch quota for plaice and cod had a limited effect on benthic impact, except when reduced to very low values, forcing the vessels to stay in port. Quota management had a minimal influence on fishing behaviour and hence resulted in a minimal reduction of benthic impact. Habitat credits may reduce the benthic impacts of the trawl fisheries at a minimal loss of landings and revenue, as vessels are still able to reallocate their effort to less vulnerable fishing grounds, while allowing the fishery to catch their catch quota and maintain their revenue. Only if they are reduced to extremely low levels can habitat credits potentially constrain fishing activities to levels that prevent the fisheries from using up the catch quota for the target species.
Land–sea ecological connectivity refers to the interaction (convenience or hindrance) of certain physical, chemical and biological processes between terrestrial and marine ecosystems. Research on land–sea ecological connectivity can provide important scientific bases for the conservation and restoration of biodiversity and ecosystems in terrestrial and coastal areas. On the basis of a literature summary of ecological connectivity, this paper focuses on the following: (1) summarizing basic concepts, representative phenomena on multiple spatiotemporal scales, and analysis methods of land–sea ecological connectivity; (2) discussion of the applications of land–sea ecological connectivity; (3) discussion of the relationship between human activities and land–sea ecological connectivity; (4) presentation of perspectives and recommendations on ecological restoration, protection, and biodiversity research, with emphasis on the principle of land–sea ecological connectivity. On the whole, we believe such connectivity in a region varies with changes in multiple physical and artificial factors, such as climate, land cover, biotic community and human activities. Human activities such as land use, engineering construction, urbanization and industrialization have continuously increased and cause irreversible disturbance and destruction of land–sea ecological connectivity, thereby threatening biodiversity and ecosystem services at various spatiotemporal scales. Hence, achievements of theoretical research and practical experience in ecological connectivity should be fully applied in coastal areas to maintain and restore land–sea ecological connectivity and remedy various problems that arise from the blockage and damage of ecosystem services.
Human population growth since the mid-1900s has been accompanied by an unsustainable use of natural resources and a corresponding impact on terrestrial and marine biota. In response, most states have established protected areas as tools to decrease biodiversity loss, being Chile one of the signatories of international conservation agreements such as the Convention on Biological Diversity (CBD) and the 2010 Aichi Targets. This study reviews the Chilean protected areas that have been created to date, with an emphasis on the existence and effectiveness of management plans for all terrestrial and marine protected areas.
Effectiveness was individually evaluated using two filters: 1) the age of the management plan and 2) the first four steps of the Protected Areas Management Effectiveness (PAME) methodology recommended by the IUCN.
We show that 84 out of a total of 145 protected areas (PAs), and only five out of a total of 20 marine protected areas (MPAs), have management plans. Only 12% (N = 16) of PAs are effectively managed; while in the marine realm, no MPA has an effective plan.
Our results show the lack of both the effectiveness of and updates to the management plans for the vast majority of the national territory and raise the following question: is it sustainable to continue adding protected areas to the national system even though it is clear that the existing support is insufficient to meet the minimum requirements for full implementation?
In this study we investigate if eutrophication management has the potential to substantially affect which areas are going to be most suitable for commercial fishing in the future. We use a spatial ecosystem model, forced by a coupled physical-biogeochemical model, to simulate the spatial distribution of functional groups within a marine ecosystem, which depends on their respective tolerances to abiotic factors, trophic interactions, and fishing. We simulate the future long-term spatial developments of the community composition and their potential implications for fisheries under three different nutrient management scenarios and changing climate. The three nutrient management scenarios result in contrasting developments of bottom oxygen concentrations and phytoplankton abundance, with substantial effects on fish production. Nutrient load reduction increases the spatial extent of the areas suitable for the commercially most valuable demersal fish predator and all types of fisheries. This suggests that strategic planning of fishery management strategies could benefit from considering future changes in species distributions due to changes in eutrophication. We show that combining approaches from climate research, physical oceanography, biogeochemistry, biogeography, and trophic ecology with economical information provides a strong foundation to produce scientific knowledge that can support a multisectoral management of ecosystems.
Genetic diversity confers adaptive capacity to populations under changing conditions but its role in mediating impacts of climate change remains unresolved for most ecosystems. This lack of knowledge is particularly acute for foundation species, where impacts may cascade throughout entire ecosystems. We combined population genetics with eco-physiological and ecological field experiments to explore relationships among latitudinal patterns in genetic diversity, physiology and resilience of a kelp ecosystem to climate stress. A subsequent ‘natural experiment’ illustrated the possible influence of latitudinal patterns of genetic diversity on ecosystem vulnerability to an extreme climatic perturbation (marine heatwave). There were strong relationships between physiological versatility, ecological resilience and genetic diversity of kelp forests across latitudes, and genetic diversity consistently outperformed other explanatory variables in contributing to the response of kelp forests to the marine heatwave. Population performance and vulnerability to a severe climatic event were thus strongly related to latitudinal patterns in genetic diversity, with the heatwave extirpating forests with low genetic diversity. Where foundation species control ecological structure and function, impacts of climatic stress can cascade through the ecosystem and, consequently, genetic diversity could contribute to ecosystem vulnerability to climate change.
Coastal vulnerability is a spatial concept that identifies people and places that are susceptible to disturbances resulting from coastal hazards. Hazards in the coastal environment, such as coastal storms and erosion, pose significant threats to coastal physical, economic, and social systems. The theory of vulnerability has been an evolving idea over the past hundred years. In recent decades, improved technology and high-profile disaster events, has caused an increase in publications in the coastal hazards field. Modern approaches to understanding coastal vulnerability examine the complex systems that determine the spatial distribution of hazards, risks, and exposure. Consensus among today’s researchers shows that coastal vulnerability is geographically dependent and requires place based investigations. This review examines over 200 coastal vulnerability related works. Through this extensive literature review, this research describes the evolution of vulnerability concepts, and the modern definition of vulnerability with the goal of providing a well-informed body of knowledge to be used in the advancement of resilience and increased sustainability in coastal areas.
This paper provides an overview of existing literature on vessel/ship detection and classification from optical satellite imagery. Although SAR (Synthetic Aperture Radar) is still the leading technology for maritime monitoring, the number of studies based on optical satellite data is quickly growing. Altogether we analysed 119 papers on optical vessel detection and classification for the period from 1978 to March 2017. We start by introducing all the existing sensor systems for vessel detection, but subsequently focus only on optical imaging satellites. The article demonstrates the temporal development of optical satellite characteristics and connects this to the number and frequency of publications on vessel detection. After presenting the methods used for optical imagery-based vessel detection and classification in detail, along with the achieved detection accuracies, we also report possibilities for fusing optical data with other data sources. The studied papers show that the most common factors greatly influencing the vessel detection accuracy are the following: different weather conditions affecting sea surface characteristics, the quantity of clouds and haze, solar angle, and imaging sensor characteristics. All these factors bring great variations in the selection of the most suitable method; some still continue to pose unsolved challenges. For higher relevance and wider usage, we suggest that the algorithms for detection and classification should support a variety of targets and meteorological conditions, and ideally also a variety of optical satellite sensors. At least, they should be tested on many images under different conditions. This is not usually the case in the existent literature. We also observed that many authors omit an appropriate performance quantification, which is critical for a practical assessment and a numerical comparison of the presented algorithms. Overall it can be seen that vessel monitoring from spaceborne optical images is a popular research topic and has a great operational potential in the near future due to the large amount of satellite data, much of it free and open.
Rare species typically contribute more to functional diversity than common species. However, humans have altered the occupancy and abundance patterns of many species—the basis upon which we define “rarity.” Here, we use a globally unique dataset from hydrothermal vents—an untouched ecosystem—to test whether rare species over-contribute to functional diversity.
Juan de Fuca Ridge hydrothermal vent fields, Northeast Pacific Ocean.
We first conduct a comprehensive review to set up expectations for the relative contributions of rare and common species to functional diversity. We then quantify the rarity and commonness of 37 vent species with relevant trait information to assess the relationship between rarity and functional distinctiveness—a measure of the uniqueness of the traits of a species relative to traits of coexisting species. Next, we randomly assemble communities to test whether rare species over-contribute to functional diversity in artificial assemblages ranging in species richness. Then, we test whether biotic interactions influence functional diversity contributions by comparing the observed contribution of each species to a null expectation. Finally, we identify traits driving functional distinctiveness using a distance-based redundancy analysis.
Across functional diversity metrics and species richness levels, we find that both rare and common species can contribute functional uniqueness. Some species always offer unique trait combinations, and these species host bacterial symbionts and provide habitat complexity. Moreover, we find that contributions of species to functional diversity may be influenced by biotic interactions.
Our findings show that many common species make persistent, unique contributions to functional diversity. Thus, it is key to consider whether the abundance and occupancy of species have been reduced, relative to historical baselines, when interpreting the contributions of rare species to functional diversity. Our work highlights the importance of testing ecological theory in ecosystems unaffected by human activities for the conservation of biodiversity.
Vocal imitation is a hallmark of human spoken language, which, along with other advanced cognitive skills, has fuelled the evolution of human culture. Comparative evidence has revealed that although the ability to copy sounds from conspecifics is mostly uniquely human among primates, a few distantly related taxa of birds and mammals have also independently evolved this capacity. Remarkably, field observations of killer whales have documented the existence of group-differentiated vocal dialects that are often referred to as traditions or cultures and are hypothesized to be acquired non-genetically. Here we use a do-as-I-do paradigm to study the abilities of a killer whale to imitate novel sounds uttered by conspecific (vocal imitative learning) and human models (vocal mimicry). We found that the subject made recognizable copies of all familiar and novel conspecific and human sounds tested and did so relatively quickly (most during the first 10 trials and three in the first attempt). Our results lend support to the hypothesis that the vocal variants observed in natural populations of this species can be socially learned by imitation. The capacity for vocal imitation shown in this study may scaffold the natural vocal traditions of killer whales in the wild.
The Marine Stewardship Council (MSC) eco—label certifies that seafood comes from a sustainable source. The use of this eco—label lags behind in the developing world, where ecosystem approaches to fishery management have not yet been widely implemented. However, the Food and Agriculture Organization under its REBYC—II LAC project is addressing ecosystem concerns within the shrimp trawl fisheries of a number of developing countries in Latin America and the Caribbean by helping them to improve management of the negative ecosystem impacts by modifying their gear to reduce by—catch and habitat damage. This study investigates how the potential improvements identified by the REBYC—II LAC project will help in satisfying the requirements for obtaining an MSC certification in the Campeche shrimp fishery in Mexico. The feasibility and desirability of obtaining an MSC certification in this fishery was assessed by interviewing managers, fishers, processors, and other relevant stakeholders of the fishery. By comparing the MSC certification requirements with the current conditions of the Campeche shrimp fishery, this paper shows that the fishery is currently not certifiable. Although the REBYC—II LAC project could represent a significant step towards the potential certification of the fishery, further actions will need to be implemented by the Mexican management authorities and private sector, if certification is sought. This paper should help guide the Campeche shrimp industry and fishery managers towards the necessary steps for achieving sustainability.
Feeding wildlife for the purpose of tourism is a contentious issue with for and against arguments being raised by tour operators, non-governmental organisations, researchers, and managers. Despite this situation, there is a growing trend in the feeding of marine wildlife to guarantee visitors an exciting up-close experience. This review investigates the scope and key findings of research conducted on the impacts and social aspects of tourism related wild fish feeding. This systematic quantitative literature review identified 58 peer-reviewed articles on feeding wild fish for tourism. Of those articles, 35 (60%) reported on ecological impacts on the fish. Only 14 articles explored fish feeding tourism from a social perspective, and of those only 9 (15%) investigated the perspectives of visitors. This review highlights that the impacts and management of complex human-wildlife interactions, such as feeding wild fish, are case and species specific. The impacts of feeding wild fish for tourism include changes in species distribution and behaviour, negative health effects, increased predation of some fish species, and risk of injury to tourists. There is less research on social aspects such as visitor attitudes and satisfaction with fish feeding operations. Further studies are required on visitor demand and interests, and the ecological implications of provisioning to ensure the scenarios in which fish feeding occur are sustainable, maximizing the tourism experience while minimizing negative impacts on fish populations. It is important that progress is made towards developing appropriate codes of conduct and nationally and internationally accredited standards of practice.
The extensive pressures upon current commercial fisheries, compounded by the projected impacts of climate change and associated processes on marine ecosystems, will increasingly displace elements of future fishing effort towards new locations, target species and techniques. For transboundary stocks, where a new or exploratory fishery is contemplated, Article 6(6) of the UN Fish Stocks Agreement 1995 mandates cautious conservation measures to acquire sufficient catch data to assess the impacts of fishing on the stock and surrounding ecosystem. Thereafter, if appropriate, measures may be adopted to facilitate the gradual development of the fishery and its eventual transition to commercial management. However, there has been minimal analysis of the regulatory requirements for emergent fisheries during this interim stage. This article accordingly collates and evaluates the current international law and practice towards new and exploratory fisheries, with particular reference to Antarctic developments and the protection of vulnerable marine ecosystems from proliferating deep-sea fisheries.
Global climate models were used to assess changes in the mean, variability and extreme sea surface temperatures (SSTs) in northern oceans with a focus on large marine ecosystems (LMEs) adjacent to North America, Europe, and the Arctic Ocean. Results were obtained from 26 models in the Community Model Intercomparison Project Phase 5 (CMIP5) archive and 30 simulations from the National Center for Atmospheric Research Large Ensemble Community Project (CESM-LENS). All of the simulations used the observed greenhouse gas concentrations for 1976–2005 and the RCP8.5 “business as usual” scenario for greenhouse gases through the remainder of the 21st century. In general, differences between models are substantially larger than among the simulations in the CESM-LENS, indicating that the SST changes are more strongly affected by model formulation than internal climate variability. The annual SST trends over 1976–2099 in the 18 LMEs examined here are all positive ranging from 0.05 to 0.5°C decade–1. SST changes by the end of the 21st century are primarily due to a positive shift in the mean with only modest changes in the variability in most LMEs, resulting in a substantial increase in warm extremes and decrease in cold extremes. The shift in the mean is so large that in many regions SSTs during 2070–2099 will always be warmer than the warmest year during 1976–2005. The SST trends are generally stronger in summer than in winter, as greenhouse gas heating is integrated over a much shallower climatological mixed layer depth in summer than in winter, which amplifies the seasonal cycle of SST over the 21stcentury. In the Arctic, the mean SST and its variability increases substantially during summer, when it is ice free, but not during winter when a thin layer of ice reforms and SSTs remain near the freezing point.
The conservation of biological diversity represents a major challenge for modern societies. Research offers the fundamental information to advance and integrate our knowledge on ecological systems, their processes and interactions. Yet, the transfer of scientific knowledge and results represents a critical step towards enhancing conservation efficiency. Here, we use sea turtle research, as an example to test the potential and dynamics of international scientific cooperation reflecting the advancement of knowledge. The selection of sea turtles as a case study was mainly based on two factors. First, they represent a highly mobile group of species with cosmopolitan distribution that cross geopolitical borders, policies and agreements. Second, encouraging evidence on global population recovery are increasingly presented. We used research publications on sea turtles (from 1967 since 2016) as the main product of scientific knowledge, to develop a series of co-authorship networks. Countries that were mentioned in authors’ affiliations were used as nodes, with two nodes being connected if authors of these countries had collaborated as co-authors in a publication. The properties of the co-authorship networks revealed that sea turtle scientific collaboration networks are ] getting larger and spreading constantly over different countries through time. Network metrics revealed a robust and coherent network supported by numerous countries. Our results showed a steady flow of scientific information among countries within sea turtle research communities, a factor that might have contributed to the encouraging evidence on sea turtle population trends observed globally. This analysis highlights the potential benefits generated by international collaborations reflecting the integration of skills, scientific backgrounds and knowledge.
In the coming decades, environmental change like warming and acidification will affect life in the ocean. While data on single stressor effects on fish are accumulating rapidly, we still know relatively little about interactive effects of multiple drivers. Of particular concern in this context are the early life stages of fish, for which direct effects of increased CO2 on growth and development have been observed. Whether these effects are further modified by elevated temperature was investigated here for the larvae of Atlantic herring (Clupea harengus), a commercially important fish species. Over a period of 32 days, larval survival, growth in size and weight, and instantaneous growth rate were assessed in a crossed experimental design of two temperatures (10°C and 12°C) with two CO2 levels (400 μatm and 900 μatm CO2) at food levels mimicking natural levels using natural prey. Elevated temperature alone led to increased swimming activity, as well as decreased survival and instantaneous growth rate (Gi). The comparatively high sensitivity to elevated temperature in this study may have been influenced by low food levels offered to the larvae. Larval size, Gi and swimming activity were not affected by CO2, indicating tolerance of this species to projected "end of the century" CO2 levels. A synergistic effect of elevated temperature and CO2 was found for larval weight, where no effect of elevated CO2 concentrations was detected in the 12°C treatment, but a negative CO2 effect was found in the 10°C treatment. Contrasting CO2 effects were found for survival between the two temperatures. Under ambient CO2 conditions survival was increased at 12°C compared to 10°C. In general, CO2 effects were minor and considered negligible compared to the effect of temperature under these mimicked natural food conditions. These findings emphasize the need to include biotic factors such as energy supply via prey availability in future studies on interactive effects of multiple stressors.
Ecosystem-based fisheries management (EBFM) was developed to move beyond single species management by incorporating ecosystem considerations for the sustainable utilization of marine resources. Due to the wide range of fishery characteristics, including different goals of fisheries management across regions and species, theoretical best practices for EBFM vary greatly. Here we highlight the lack of consensus in the interpretation of EBFM amongst professionals in marine science and its implementation. Fisheries policy-makers and managers, stock assessment scientists, conservationists, and ecologists had very different opinions on the degree to which certain management strategies would be considered EBFM. We then assess the variability of the implementation of EBFM, where we created a checklist of characteristics typifying EBFM and scored fisheries across different regions, species, ecosystems, and fishery size and capacity. Our assessments show fisheries are unlikely to meet all the criteria on the EBFM checklist. Consequentially, it is unnecessary for management to practice all the traits of EBFM, as some may be disparate from the ecosystem attributes or fishery goals. Instead, incorporating some ecosystem-based considerations to fisheries management that are context-specific is a more realistic and useful way for EBFM to occur in practice.
Elasmobranchs are among the most threatened long-lived marine species worldwide, and incidental capture is a major source of mortality. The northern central Adriatic Sea, though one of the most overfished basins of the Mediterranean Sea, supports a very valuable marine biodiversity, including elasmobranchs. This study assesses the impact of the northern central Adriatic pelagic trawl fishery on common smooth-hound (Mustelus mustelus), spiny dogfish (Squalus acanthias), common eagle ray (Myliobatis aquila), and pelagic stingray (Pteroplatytrygon violacea) by examining incidental catches recorded between 2006 and 2015. The distribution of bycatch events was evaluated using geo-referenced data. Generalized Linear Models were computed to standardize the catch of the four species and to predict the relative abundance of bycatch events. Data analysis shows that most bycatch events involving all four species occurred in the northern Adriatic Sea. The models predicted significant, distinct temporal patterns of standardized catches in line with previous investigations. Water depth, season, and fishing region were the best predictors to explain bycatch events. The present data suggest that the northern Adriatic may be an important nursery area for several elasmobranchs. They also highlight the urgent need for a better understanding of the interactions between elasmobranchs and fisheries to develop and apply suitable, ad hoc management measures.
Marine reserves are implemented to achieve a variety of objectives, but are seldom rigorously evaluated to determine whether those objectives are met. In the rare cases when evaluations do take place, they typically focus on ecological indicators and ignore other relevant objectives such as socioeconomics and governance. And regardless of the objectives, the diversity of locations, monitoring protocols, and analysis approaches hinder the ability to compare results across case studies. Moreover, analysis and evaluation of reserves is generally conducted by outside researchers, not the reserve managers or users, plausibly thereby hindering effective local management and rapid response to change. We present a framework and tool, called “MAREA”, to overcome these challenges. Its purpose is to evaluate the extent to which any given reserve has achieved its stated objectives. MAREA provides specific guidance on data collection and formatting, and then conducts rigorous causal inference analysis based on data input by the user, providing real-time outputs about the effectiveness of the reserve. MAREA’s ease of use, standardization of state-of-the-art inference methods, and ability to analyze marine reserve effectiveness across ecological, socioeconomic, and governance objectives could dramatically further our understanding and support of effective marine reserve management.