- Scientists became aware of the ocean plastics problem in the 1950s, and understanding of the nature and severity of the problem grew over the next decades.
- The major chemical and petroleum companies and industry groups were aware of the ocean plastics problem no later than the 1970s.
- Plastics producers have often taken the position that they are only responsible for plastic waste in the form of resin pellets, and that other forms of plastic waste are out of their control.
Climate models provide the principal means of projecting global warming over the remainder of the twenty-first century but modelled estimates of warming vary by a factor of approximately two even under the same radiative forcing scenarios. Across-model relationships between currently observable attributes of the climate system and the simulated magnitude of future warming have the potential to inform projections. Here we show that robust across-model relationships exist between the global spatial patterns of several fundamental attributes of Earth’s top-of-atmosphere energy budget and the magnitude of projected global warming. When we constrain the model projections with observations, we obtain greater means and narrower ranges of future global warming across the major radiative forcing scenarios, in general. In particular, we find that the observationally informed warming projection for the end of the twenty-first century for the steepest radiative forcing scenario is about 15 per cent warmer (+0.5 degrees Celsius) with a reduction of about a third in the two-standard-deviation spread (−1.2 degrees Celsius) relative to the raw model projections reported by the Intergovernmental Panel on Climate Change. Our results suggest that achieving any given global temperature stabilization target will require steeper greenhouse gas emissions reductions than previously calculated.
Recreational beaches are strategic ecosystems for tourism and should be used in a sustainable manner. We studied three beaches in the municipality of Guaymas (NW Mexico), in order to assess their beach quality and identify key management issues. The evaluation was based on the perceptions of users concerning: (1) the user profile; (2) the recreational habits of users; and (3) the biophysical characteristics, infrastructure, services, and cleanliness of each beach. The results showed that the beaches were of different quality. The key management issues identified were the need to design and apply specific management programs for each beach, specifically in regards to improving infrastructure and services, and obtaining certification as a sustainable beach. The evaluation of the beaches as perceived by users suggests that it would be useful to assess beach quality in order to support management goals and be applicable to other beaches, both nationally and internationally.
Coastal and marine ecosystems around the world are under threat from a growing number of anthropogenic impacts, including climate change. Resource managers, researchers, policy makers, and coastal community planners are tasked with identifying, developing, and monitoring strategies to reduce or reverse the ecological, economic and social impact of environmental stressors. These individuals must make decisions about how to prioritize and allocate finite resources to address these issues, all under conditions of significant uncertainty about which of these stressors to address. This paper presents the results of a survey and workshop designed to rank the impact of a series of stressors on four components of the marine and coastal ecosystems of the Northeast United States. The methodology described here – expert elicitation supplemented by workshop deliberations – proved to be relatively cost-effective, time-efficient, and informative for identifying priority stressors for the ecosystem components under consideration, both now and in the future.
Scuba diving has attracted increased numbers of tourists on a global scale. While the beneficial as well as detrimental impacts of scuba diving tourism have been well documented, limited research attention is given to the perspectives of dive operators with respect to sustainable development. This study examined the perspectives and experiences of dive operators in relation to sustainable resource use in Mozambique and Italy, two countries that are home to popular coastal destinations and offshore marine parks. Interviews suggested that overall operators have positive attitudes towards sustainable resource use, engaging in actions such as deploying four-stroke engines, recycling equipment and waste, and favouring electric-over fuel-powered vehicles. Yet, they do not promote sustainable resource use at the dive centre, with reasons including limited time, lack of government incentives, and absence of rebate systems. Implications were discussed for sustainable diving operations in the study areas and generally.
The United Nations Sustainable Development Goals (SDG), adopted in September 2015, are accompanied by targets which have to be met individually and collectively by the signatory states. SDG14 Life Below Water aims to lay the foundation for the integrated and sustainable management of the oceans. However, any environmental management has to be based around targets which are SMART – specific, measurable, achievable, realistic and time bounded – otherwise it is not possible to determine whether management actions are successful and achieve the desired aims. The discussion here shows that many of the targets adopted for SDG14, and especially a detailed analysis of Target 1, are aspirational rather than fully quantified. In order to move towards making the targets operational, we advocate merging the language of environmental management with that used by industry for linking risks to the environment, management performance and ensuing controls. By adopting an approach which uses Key Performance Indicators (‘KPIs’), Key Risk Indicators (‘KRIs’) and Key Control Indicators (‘KCIs’), we advocate that a degree of rigour leading to defendable actions can be brought to marine management.
Databases are systematic tools to archive and manage information related to marine mammal stranding and mortality events. Stranding response networks, governmental authorities and non-governmental organizations have established regional or national stranding networks and have developed unique standard stranding response and necropsy protocols to document and track stranded marine mammal demographics, signalment and health data. The objectives of this study were to (1) describe and review the current status of marine mammal stranding and mortality databases worldwide, including the year established, types of database and their goals; and (2) summarize the geographic range included in the database, the number of cases recorded, accessibility, filter and display methods. Peer-reviewed literature was searched, focussing on published databases of live and dead marine mammal strandings and mortality and information released from stranding response organizations (i.e. online updates, journal articles and annual stranding reports). Databases that were not published in the primary literature or recognized by government agencies were excluded. Based on these criteria, 10 marine mammal stranding and mortality databases were identified, and strandings and necropsy data found in these databases were evaluated. We discuss the results, limitations and future prospects of database development. Future prospects include the development and application of virtopsy, a new necropsy investigation tool. A centralized web-accessed database of all available postmortem multimedia from stranded marine mammals may eventually support marine conservation and policy decisions, which will allow the use of marine animals as sentinels of ecosystem health, working towards a ‘One Ocean-One Health’ ideal.
Out of nearly 30,000 teleosts dwelling in our planet's water bodies, only hundreds of them are commercially exploited and prevail on the global food market. Yet, our estimates of the species actually underpinning global trade is severely hampered by inaccuracy and non-compliance in labelling and reporting. Here, we target ethnic food stores in two British cities (Liverpool and Manchester metropolitan areas), whose numbers are increasing throughout Europe, to examine accuracy of traceability information available to consumers. Despite the existence of thorough EU labelling regulations, we unveil a high level of non-compliance, with a diverse range of poorly-known fish species, often sold without any label or with erroneous information, as demonstrated by DNA barcoding. Results indicate that about 41% of the samples were mislabelled, in stark contrast with a recent study that, in 2015, found < 5% mislabelling in EU supermarkets and fishmongers. These results highlight that inspectors and governments might not be fully aware of the wide diversity of fish species traded, indicating the need for a stronger enforcement of the EU labelling legislations. Compliance with regulations is required not only to protect consumers, but also fish stocks, as for many of the species identified in this survey, population assessment is poor or lacking altogether.
The ecosystem approach to fisheries management requires ecosystems to be perceived in a holistic way, including the dynamics not only within an ecosystem but also between the ecosystem and society. This implies that people involved in decision-making processes should understand why fish and fisheries are important for society, that is, be aware of the socio-cultural values that people associate with fisheries. In this paper, the justification theory of Boltanski and Thévenot is applied to material collected through a literature review to identify socio-cultural values relating to Baltic salmon, and the potential of the approach for fisheries governance is discussed. The analysis demonstrates that fish resources can have multiple meanings to society. Justification theory is found useful for identifying socio-cultural values related to fisheries, since it suggests shifting attention from opposing interests to the common good. Agreeing on the common good is crucial for the legitimacy of governance. However, because the common good can be defined in multiple ways, these definitions have to be made transparent through empirical analysis so that they can be further deliberated, evaluated and agreed upon by governors, stakeholders and others involved.
With over 1 billion people currently relying on the services provided by marine ecosystems – e.g. food, fibre and coastal protection – governments, scientists and international bodies are searching for innovative research to support decision-makers in achieving the Sustainable Development Goals (SDGs). Valuing past and present ecosystem services allows investigation into how different scenarios impact the SDGs, such as economic growth, sustainability, poverty and equity among stakeholders. This paper investigates the past and current value of the lobster fishery located in the Table Mountain National Park Marine Protected Area. It then uses InVEST to highlight future changes under different scenarios. While we found a significant decline in fishery value over the next ten years under all three scenarios, the exclusion of large-scale fisheries from the marine protected area seems to yield the most positive results in regard to South Africa’s SDG commitments. This scenario has the potential to generate approximately 50% more revenue, while also producing the highest available protein to local communities, highest quantity of spawners and highest economic distribution to small-scale fisheries. It is clear through this research that valuing ecosystem services can enable a future of healthy economies, people and environments; the highly sought-after triple-bottom line.
Resource monitoring is a key issue in ecosystem management especially for marine protected areas (MPAs), where information on the composition and structure of fish assemblages is crucial to design a suitable management process. Data on fish assemblage are usually collected using underwater visual censuses (UVC). However, fish assemblages monitoring in MPAs usually calls for considerable resources in terms of costs, time and technical/scientific skills. Financial resources and trained scientific divers may, however, not be available in certain geographical areas, that are thus understudied. Therefore, involving citizen volunteer divers in fish assemblage monitoring and adopting easy-to-use underwater visual census methods could be an effective way to collect crucial data. Citizen science can be used only if it can provide information that is consistent with that collected using standard scientific monitoring. Here, we aim: 1) to compare the consistency of results from a Standard scientific UVC (S-UVC) and an Easy-to-use UVC (E-UVC) method in assessing fish assemblage spatial variability, and 2) to test the consistency of data collected by Scientific Divers (SD) and Scientifically-Trained Volunteer divers (STV), using E-UVC. We used, in two consecutive years, three Tunisian future Marine Protected Areas (MPAs) and adjacent areas as case studies. E-UVC and S-UVC data were consistent. Both methods reported the same spatial patterns for the three MPAs (between MPAs and, inside and outside each one), highlighting the consistency between S-UVC and E-UVC. No significant difference was recorded between data collected by SD or STV. Our results suggest that E-UVC can provide information representing simplified proxies for describing fish assemblages and can therefore be a valuable tool for fish monitoring by citizen divers in understudied areas. This evidence could foster citizen science as an effective tool to raise environmental awareness and involve stakeholders in resource management.
The sensitivity of Antarctic sea-ice to increasing glacial freshwater release into the Southern Ocean is studied in a series of 31-year ocean/sea-ice/iceberg model simulations. Glaciological estimates of ice-shelf melting and iceberg calving are used to better constrain the spatial distribution and magnitude of freshwater forcing around Antarctica. Two scenarios of glacial freshwater forcing have been designed to account for a decadal perturbation in glacial freshwater release to the Southern Ocean. For the first time, this perturbation explicitly takes into consideration the spatial distribution of changes in the volume of Antarctic ice shelves, which is found to be a key component of changes in freshwater release. In addition, glacial freshwater-induced changes in sea ice are compared to typical changes induced by the decadal evolution of atmospheric states. Our results show that, in general, the increase in glacial freshwater release increases Antarctic sea ice extent. But the response is opposite in some regions like the coastal Amundsen Sea, implying that distinct physical mechanisms are involved in the response. We also show that changes in freshwater forcing may induce large changes in sea-ice thickness, explaining about one half of the total change due to the combination of atmospheric and freshwater changes. The regional contrasts in our results suggest a need for improving the representation of freshwater sources and their evolution in climate models.
At the United Nations Ocean Conference in June 2017, Member States reaffirmed their obligation to conserve and responsibly use the oceans, seas and marine resources for sustainable development. Promoting the use of effective and appropriate area- based management tools, such as marine protected areas, was among the renewed pledges. Marine protected areas o er one of the best options for maintaining healthy oceans. In the last decade, countries around the world have progressively taken actions to designate new, or to enlarge existing, marine protected areas to safeguard natural resources and ecological functions. To date, around 14.4 per cent of the world’s coastal and marine areas under national jurisdictions are declared protected. This signals the commitment of the global community to safeguard these precious ecosystems. For marine protected areas to be truly effective, however, they also require strong governance that involves relevant users and stakeholders, influences their behaviour, and ultimately reduces the impacts that result from extractive practices. Effective sharing of costs and benefits of marine protected areas is an essential step to ensure genuine sustainable development.
A growing number of studies have documented increasing dominance of warm-water fish species (“tropicalisation”) in response to ocean warming. Such reorganization of communities is starting to occur in a multitude of local ecosystems, implying that tropicalisation of marine communities could become a global phenomenon. Using 32 years of trawl surveys in the Bay of Somme (English Channel, France), we aimed to investigate the existence of a tropicalisation in the fish community at the local scale of the estuary during the mid-1990s, a period where an exceptional temperature rise occurred in Northeast Atlantic. A long-term response occurred (with a major transition over 6 years) that was characterized by a marked diminution in the abundance of cold-water species in parallel to a temperature rise generated by the ocean-scale phenomenon, the Atlantic Multidecadal Oscillation, which switched from a cool to a warm phase during the late 1990s. Despite finding no significant increase in the dominance of warm-water species, the long-term diminution of cold-water species suggests that the restructuring of the fish community was mainly influenced by global-scale environmental conditions rather than local ones and that indirect effects may also occurred through biological interactions.
Highly dynamic ocean environments can experience dramatic changes over relatively short timeframes, affecting the spatial distribution of resources and therefore the presence or absence of highly mobile species. We use simulation studies to investigate how different temporal resolutions might affect the results of species distribution models for highly mobile species (e.g. cetaceans) in marine environments.
Azores archipelago, Portugal.
We developed three virtual species with different habitat preferences influenced by (1) only static (topographic), (2) only dynamic (oceanographic), and (3) both dynamic and static variables. Assuming that species would reposition themselves daily according to these preferences (as has been observed for large marine foragers such as cetaceans), we used two different approaches (generalized linear model and generalized boosted model) to test the effect of using daily, weekly and monthly environmental datasets to model distributions.
The results showed that the selection of different temporal scales has a very important effect on model predictions. When dynamic variables are important components of habitat preference, models based on daily or weekly timeframes performed best at reconstructing the known niche.
It is important that we consider temporal resolution when applying species distribution models. Several factors (e.g. species ecology and oceanographic characteristics of the ecosystem) should be taken into consideration when selecting an adequate temporal scale for niche modelling. For fine scale applications (e.g. dynamic ocean management), highly dynamic ecosystems, and highly mobile species, our results suggest exploring temporal resolution of 7–8 days rather than coarser temporal scales. For some applications annual, seasonal or even monthly averages may produce inferior or inaccurate models.
The oceans absorb ~25% of the annual anthropogenic CO2 emissions. This causes a shift in the marine carbonate chemistry termed ocean acidification (OA). OA is expected to influence metabolic processes in phytoplankton species but it is unclear how the combination of individual physiological changes alters the structure of entire phytoplankton communities. To investigate this, we deployed ten pelagic mesocosms (volume ~50 m3) for 113 days at the west coast of Sweden and simulated OA (pCO2 = 760 μatm) in five of them while the other five served as controls (380 μatm). We found: (1) Bulk chlorophyll a concentration and 10 out of 16 investigated phytoplankton groups were significantly and mostly positively affected by elevated CO2 concentrations. However, CO2 effects on abundance or biomass were generally subtle and present only during certain succession stages. (2) Some of the CO2-affected phytoplankton groups seemed to respond directly to altered carbonate chemistry (e.g. diatoms) while others (e.g. Synechococcus) were more likely to be indirectly affected through CO2 sensitive competitors or grazers. (3) Picoeukaryotic phytoplankton (0.2–2 μm) showed the clearest and relatively strong positive CO2 responses during several succession stages. We attribute this not only to a CO2 fertilization of their photosynthetic apparatus but also to an increased nutrient competitiveness under acidified (i.e. low pH) conditions. The stimulating influence of high CO2/low pH on picoeukaryote abundance observed in this experiment is strikingly consistent with results from previous studies, suggesting that picoeukaryotes are among the winners in a future ocean.
Heterotrophic feeding in newly-settled coral planulae can potentially improve survivorship and accelerate early development in some species; however, an optimal diet to facilitate this does not currently exist. This study evaluated the efficacy of three heterotrophic feeding regimes (enriched rotifers, unfiltered seawater, and a novel, particulate diet), against a wholly-phototrophic treatment on Acropora hyacinthus, A. loripes, A. millepora, and A. tenuis recruits, over 93 days post-settlement. The unfiltered seawater treatment recorded maximum survival for all species (A. hyacinthus 95.9±8.0%, A. loripes: 74.3±11.5%, A. millepora: 67±12.7%, A. tenuis: 53.2±11.3%), although not significant. Growth (% surface area gain) was also greatest in the unfiltered seawater, and this was significant for A. millepora (870±307%) and A. tenuis(693±91.8%) (p<0.05). Although total lipid concentration was relatively stable across treatments, the lipid class composition exhibited species-specific responses to each treatment. Lower saturated and higher polyunsaturated fatty acids appeared beneficial to recruit performance, particularly in the unfiltered seawater, which generally contained the highest levels of 20:5n-3 (EPA), 22:6n-3 (DHA), and 20:4n-6 (ARA). The present study demonstrates the capacity of a nutritionally adequate and readily accepted heterotrophic feeding regime to increase coral recruit survival, growth, and health, which can greatly reduce the time required in cost- and labour-intensive culture.
What (and how) we grow, harvest or extract from the ocean has significant implications for long term sustainability of this immense ecosystem. Our current industrial approach to seafood harvesting is clearly not sustainable and cities can and must take the lead in developing new approaches. Urbanites must begin to shift their consumer and political power behind more sustainable ideas and practices. Some of these new approaches are explored here, including support for smaller scale, locally based fishing (and new mechanisms such as Community Supported Fisheries [CSFs]), and a shift towards more sustainable and humane forms of shellfish aquaculture and ocean vegetable farming.
International instruments of fisheries governance have set the core principles for the management of highly migratory fishes. We evaluated the progress of tuna Regional Fisheries Management Organizations (tRFMOs) in implementing the ecological component of ecosystem-based fisheries management (EBFM). We first developed a best case tRFMO for EBFM implementation. Second, we developed criteria to evaluate progress in applying EBFM against this best case tRFMO. We assessed progress of the following four ecological components: target species, bycatch species, ecosystem properties and trophic relationships, and habitats. We found that many of the elements necessary for an operational EBFM are already present, yet they have been implemented in an ad hoc way, without a long-term vision and a formalized plan. Overall, tRFMOs have made considerable progress monitoring the impacts of fisheries on target species, moderate progress for bycatch species, and little progress for ecosystem properties and trophic relationships and habitats. The tRFMOs appear to be halfway towards implementing the ecological component of EBFM, yet it is clear that the “low-hanging fruit” has been plucked and the more difficult, but surmountable, issues remain, notably the sustainable management of bycatch. All tRFMOs share the same challenge of developing a formal mechanism to better integrate ecosystem science and advice into management decisions. We hope to further discussion across the tRFMOs to inform the development of operational EBFM plans.
The marine world is, to many, remote and exotic. For city residents to fully embrace the wonder and beauty of the ocean world, and to actively work on its behalf, it will require emotional connection and caring. There are many different ways to do this and several of the more compelling and creative are described here: using social media to foster a sense of fascination and concern for the great white shark; taking children into the water and challenging them to find, look, touch and learn about the nature there; sending real-time video images from underwater divers to the surface; developing new long term institutions, such as a New York Harbor School and the Billion Oyster Project, to educate and engage residents of all ages. There are now compelling models that other cities can follow to foster this deep sense of emotional connection and caring for the marine realm.