We analysed the total mercury (Hg) accumulation in bodies and gut contents of 13 species of marine wild fish, 7 species of wild freshwater fish and 4 species of farmed fish. In addition, metal concentrations were recorded in water, sediment, fish prey and fodder materials, to track the dynamics of bio-accumulation. Cultured freshwater fish were collected at four Austrian farms and compared with samples obtained from markets. Wild marine fish were collected at Santa Croce bank, in Italy (Mediterranean Sea). Metal accumulation varied with sampling site, species, and age (or weight) of fish. Wild marine fish exhibited higher levels than wild freshwater fish, which in turn had higher Hg levels than cultured freshwater fish. Mercury increased according to trophic levels of consumers. Total Hg contents in muscle of cultured and wild freshwater fish sampled in 2006-2008 did not exceed legal nutritional limits. Similarly, in market samples of trout and carp collected in 2019, we found low or undetectable concentrations of total Hg in muscle tissue. In contrast, some marine fish (both market samples and some species from coastal waters) exceeded the legal limits. Environmental contamination, food webs and biological factors are the main causes of Hg accumulation in fish. Our results reflect the actual differences between specific European sites and should not be generalized. However, they support the generally increasing demand for monitoring mercury pollution in view of its impact on human health and its value as an indicator of ecosystem contamination.
Current and future prospects for successfully rebuilding global fisheries remain debated due to uncertain stock status, variable management success, and disruptive environmental change. While scientists routinely account for some of this uncertainty in population models, the mechanisms by which this translates into decision-making and policy are problematic and can lead to unintentional overexploitation. Here, we explicitly track the role of measurement uncertainty and environmental variation in the decision-making process for setting catch quotas. Analyzing 109 well-sampled stocks from all oceans, we show that current practices may attain 55% recovery on average, while richer decision methods borrowed from robotics yield 85% recovery of global stocks by midcentury, higher economic returns, and greater robustness to environmental surprises. These results challenge the consensus that global fisheries can be rebuilt by existing approaches alone, while also underscoring that rebuilding stocks may still be achieved by improved decision-making tools that optimally manage this uncertainty.
In post-disaster recovery phases, many communities reduce their vulnerabilities to future disasters by implementing community-based approaches. However, since these processes impact resource allocation, access to natural resources, and benefit distributions, these efforts have changed the environment and altered social relations. Therefore, this research explores how disaster empowers or disempowers stakeholders by investigating the interdependence of social relations in post-disaster natural resource management. After the 2004 Indian Ocean Tsunami, the island of Koh Klang demonstrated resilience in restoring its ecosystem. We have used this as a case study featuring a community-based project. Interviews and participant observations were conducted in the field in 2014 to collect firsthand information from local residents, NGOs, and the public sector. Text and discourse analyses were conducted based on interview data, government documents, and field notes. The findings show that after a disaster, natural resources and embedded social norms form the basis for a resilient community. Using community- and ecosystem-based methods fosters a community's environmental and social resilience and prepares it to respond to future disasters. However, such methods can also transform local politics, especially when residents' inequitable vulnerabilities and access to power are coupled with jurisdictional and land tenure issues. This research recommends that disaster recovery and mitigation policies are scaled to local levels.
Pollution by microplastics and antibiotics is an emerging environmental, human and animal health threat. In spite of several studies documenting the widespread occurrence of plastic debris in aquatic ecosystems, research focusing on occurrence and concentration of biological and chemical contaminants attached on microplastic surface as well as on possible interactions of these contaminants with microplastics is still at its beginning. The present note addresses the role of microplastics as vectors of contaminants in water bodies, stressing the need for future investigations on this hot topic.
This paper draws from ethnographic fieldwork conducted between August–October 2014 and July–August 2015 in a rural village located inside of a Tanzanian marine park. Through narrative responses elicited during interviews with village residents, coupled with ethnographic vignettes from a key interlocutor in the village, the paper reveals people's diverse perspectives on village out-migration. In doing so, it interrogates the claim that the marine park has forced people to out-migrate. Some respondents explained that men generally engage in circular forms of labour-related mobility in the context of seasonal fishing activities and short-term business ventures. Others said that people choose to out-migrate due to everyday hardships, leaving “in search of a good life.” These narrative responses are at once commentaries on the macro-level political and economic drivers of rural out-migration, and on respondent's micro-level aspirations for future socioeconomic autonomy. Thus, they are both expressions of structural constraint and individual agency. While very few interviewees believed that people were forced to migrate because of the marine park, most respondents contended that it had deepened pre-existing experiences of a “hard life,” and exacerbated lived experiences of vulnerability. However, migration has historically been woven into the sociocultural fabric of the community, and there are broader trends of rural population mobility in Tanzania, and fisher mobility in coastal areas, which long pre-date the establishment of the park. Furthermore, some respondents offered alternative narratives, noting that villagers may choose not to out-migrate, and that village in-migration may be increasing due to various pull factors. As such, the paper complicates the scholarly discourse on the relationship between marine protected areas and displacement of local communities.
Scuba diving continues to be one of the most popular recreational activities in marine tourism, but its sustainability is currently threatened due to environmental, social, political, and economic risks. The East African Marine Ecoregion is renowned for its richness in marine fauna and flora, including some of the Indian Ocean's most diverse and abundant coral reef ecosystems, making it a popular destination for scuba divers. However, empirical evidence suggests that external risks (international and domestic) are impacting on dive operators in the region, creating the need to better understand these impacts. This research was therefore aimed at identifying the most significant of these external risks from the perspective of dive operators, via an explorative and descriptive study. The qualitative and quantitative primary data collected revealed that domestic and international economic and political risks have the greatest impact on dive operators in the East African Marine Ecoregion, and this trend is expected to continue. Environmental degradation of coral reefs, while not seen as a threat to dive operators at present, constitutes a key threat within the near future. In terms of the variation in perceived risk across the region, Kenya suffers most from social and political risks, Tanzania from environmental risks, Mozambique from political risks, and South Africa from economic risks. The research contributes to Africa's Blue Economy, which aims to guide African countries in sustainable use of the marine environment while harnessing its social and economic benefits. The findings create awareness of the impact of external risks on regional dive operators and their significance. Furthermore, they create an opportunity for decision makers and stakeholders in the region to craft solutions to improve the sustainability of the scuba diving industry.
In search for sustainability of the oceans, the concept of resilience arises as a necessary perspective from which to analyse what course of action to take. Resilience refers to the capacity of a system to absorb change, but also to adapt and develop in face of those changes. Resilience thinking has recently permeated the sphere of legal studies, and the two fields have been interested in exploring the impact they have on one another. To explore this interaction further in the context of the management of the oceans, the present paper looks at areas beyond national jurisdiction (ABNJ) as a socio-ecological system. It argues that the law can be a tool for improving the resilience of a system, but that it must, for that purpose, be able to ensure at least some adaptive capacity. In light of the upcoming, consolidated regime for the sustainable management of biodiversity beyond national jurisdiction (BBNJ) through the development of an internationally legally binding agreement on the topic, and considering the uncertainty surrounding our knowledge of ABNJ, this paper suggests to look at the BBNJ agreement from the perspective of resilience thinking. The paper explores how this perspective could bring new insights to the development of the BBNJ agreement, as well as the emerging literature linking law and resilience.
Marine coastal environments are often socially complex public areas that need equitable spatial planning approaches. Understanding the extent of extractive and non-extractive uses and the social dynamics that may be driving patterns of use is essential if the spatial plan is to support the social resilience of a marine area. In this study, a combination of fuzzy-set multi-criteria GIS modelling and negative tie social network analysis were used to explore social uses and conflicts based on sketch-mapping interviews with five key stakeholder groups (ecotourism, Aboriginal Traditional Owners, commercial and recreational fishing, and water sports) within a Marine Protected Area (MPA). Most of the areas within the MPA were regularly used by the stakeholders, with non-extractive and extractive stakeholders occupying similar spatial extents, with each stakeholder group having a different pattern of use. However, stakeholder groups had different levels of perceived priority to access these areas and support of the current spatial management plan, especially within the ecotourism and Aboriginal Traditional Owner groups. The investigation of social conflicts in shaping patterns of use revealed that most stakeholder conflicts do not necessarily occur in areas of overlaps, but generally in areas of high biodiversity and easy access through marine infrastructure. Ecotourism groups had the most perceived conflicts over marine space, which shaped their use towards certain no-take zones that protected high biodiversity and would also provide protection from other conflicting stakeholder uses (e.g., boating, fishing). Overall, the method outlined in this paper presents a way for marine spatial management to consider not only the extent and diversity of social uses in a marine environment but also the spatial-social dynamics that may determine the success of the spatial plan in supporting long-term social resilience.
The historic influence of interannual weather and climate variability on total mercury concentrations (THg) in the eggs of two species of Arctic seabird in the Canadian High Arctic was investigated. Time series of THg in the eggs of northern fulmars (Fulmarus glacialis) and thick-billed murres (Uria lomvia) from Prince Leopold Island span 40 years (1975–2014), making these among the longest time series available for contaminants in Arctic wildlife and uniquely suitable for evaluation of long-term climate and weather influence. We compiled a suite of weather and climate time series reflecting atmospheric (air temperature, wind speed, sea level pressure) and oceanic (sea surface temperature, sea ice cover) conditions, atmosphere-ocean transfer (snow and rain), as well as broad-scale teleconnection indices such as the Arctic Oscillation (AO) and North Atlantic Oscillation (NAO). We staggered these to the optimal time lag, then in a tiered approach of successive General Linear Models (GLMs), strategically added them to GLMs to identify possible key predictors and assess any main effects on THg concentrations. We investigated time lags of 0 to 10 years between weather/climate shifts and egg collections. For both fulmars and murres, after time lags of two to seven years, the most parsimonious models included NAO and temperature, and for murres, snowfall, while the fulmar model also included sea ice. Truncated versions of the datasets (2005–2014), reflective of typical time series length for THg in Arctic wildlife, were separately assessed and generally identified similar weather predictors and effects as the full time series, but not for NAO, indicating that longer time series are more effective at elucidating relationships with broad scale climate indices. Overall, the results suggest a significant and larger than expected effect of weather and climate on THg concentrations in Arctic seabirds.
Since 2004, when microplastics appears in literature, thousands of researchers focussed on this topic and analysed microplastics in almost every environmental compartment. However, there is still a lack of standardisation, and therefore, used methodologies varied widely. Most researchers performed controversially discussed visual examination, but it became more and more a supporting tool to reduce measuring effort. To that account, especially infrared or Ramanmicroscopy were used for chemical characterisation. This indicates that dimensions of analysed microplastics changed to micrometre scaling. However, those microscopy technologies were used for particle by particle characterisation, and therefore, it is still challenging to handle the mass of data. Alternatively, thermal extraction and desorption gas chromatography is a useful integrating analysis approach, which allows a multicomponent characterisation of environmental samples without any complex sample preparation.
Human occupation of coastal areas promotes the establishment of non-native species but information on bioinvasions is usually biased toward the Northern Hemisphere. We assessed non-native species' importance in sessile communities at six marinas along the most urbanized area of the Southwestern Atlantic coastline. We found 67 species, of which 19 are exotic. The most frequent species was the exotic polychaete Branchiomma luctuosum, while the most abundant was the exotic bryozoan Schizoporella errata that monopolized the substrata in three marinas. Along with S. errata, the exotic polychaete Hydroides elegans and ascidian Styela plicata dominated space in the three remaining marinas, while native species were in general rare. We show that communities associated with artificial substrata along this Brazilian urbanized area are dominated by exotic species and that using abundance data along with species identity can improve our understanding of the importance of exotic species for the dynamics of biological communities.
Marine recreational fishing is popular globally and benefits coastal economies and people's well‐being. For some species, it represents a large component of fish landings. Climate change is anticipated to affect recreational fishing in many ways, creating opportunities and challenges. Rising temperatures or changes in storms and waves are expected to impact the availability of fish to recreational fishers, through changes in recruitment, growth and survival. Shifts in distribution are also expected, affecting the location that target species can be caught. Climate change also threatens the safety of fishing. Opportunities may be reduced owing to rougher conditions, and costs may be incurred if gear is lost or damaged in bad weather. However, not all effects are expected to be negative. Where weather conditions change favourably, participation rates could increase, and desirable species may become available in new areas. Drawing on examples from the UK and Australia, we synthesize existing knowledge to develop a conceptual model of climate‐driven factors that could impact marine recreational fisheries, in terms of operations, participation and motivation. We uncover the complex pathways of drivers that underpin the recreational sector. Climate changes may have global implications on the behaviour of recreational fishers and on catches and local economies.
Studies of commercial fishing have shown that it is a hazardous occupation with high rates of injury and fatal accidents. Research has also identified a range of other health risks faced by fishers, yet the general health outcomes of fishers have not been compared to those of workers in other industries. This study aimed to assess self-reported health outcomes among workers in the fishing industry, and to compare this to those working in other industries. Drawing on 2011 census data for England and Wales we used generalised linear models to compare self-reported measures of 1) general health and 2) limiting long-term illness across industry categories, calculating odds ratios adjusted for age, geographic region and socio-economic profile of local authorities. Of the population working in 87 industry classes, those in category ‘03 Fishing and aquaculture’ had the fifth highest rate of poor general health (2.8% reported ‘bad’ or ‘very bad’ health) and the sixth highest rate of reporting limiting long-term illness (10.3% reported their activities to be limited ‘a lot’ or ‘a little’). Odds ratios adjusted for age, geographic region and socio-economic profile of local authorities showed that only two other industries demonstrated statistical evidence for higher odds of poor general health or limiting long-term illness than workers in fishing and aquaculture. This study demonstrates that fishing is among the industries with the poorest general health and limiting long-term illness outcomes in the UK, demonstrating the need for tailored occupational health services to support UK fishing communities.
After a spout of optimism surrounding Myanmar's so-called democratic transition in the post-2010 period, civil-society organisations and academics are beginning to highlight rampant and violent resource grabs unfolding across the country. Delving into the Northern Tanintharyi landscape in the Southeast, this article aims to understand interrelated dynamics of coastal and agrarian transformation during the state-mediated capitalist transition of the past 30 years. Conceptually developing a landscape-approach that sees individual ‘grabs’ in a relational manner and as part of broader political-economic struggles, the article shows how the Myanmar military regime sought a conjoined ocean and land control-grab in pursuit of rent extraction from productive foreign capital in fisheries and off-shore gas sectors. Empirically, these dynamics are traced from the scale of regional geopolitical struggles down to two particular villages in Northern Tanintharyi – highlighting resulting processes of differentiation along lines of class and gender. This conceptual framework and explanation of drivers behind ocean and land control-grabbing, in turn, complicates prevalent policy solutions in Myanmar (and elsewhere) that reduce the question of resolving resource-grabs to the pursuit of an elusive ‘good governance’.
There is currently no generally accepted definition for the “blue economy,” despite the term becoming common parlance over the past decade. The concept and practice have spawned a rich, and diverse, body of scholarly activity. Yet despite this emerging body of literature, there is ambiguity around what the blue economy is, what it encapsulates, and its practices. Thus far, the existing literature has failed to theorise key geographical concepts such as space, place, scale, and power relations, all of which have the potential to lead to uneven development processes and regional differentiation. Previous research has sought to clarify the ontological separation of land and sea or has conceptualised the blue economy as a complex governmental project that opens up new governable spaces and rationalises particular ways of managing marine and coastal regions. More recently, geographers have called for a critical—and practical—engagement with the blue economy. This paper critically examines the existing literature of the geographies of the blue economy through a structured meta‐analysis of published work, specifically its conceptualisations and applications to debates in the field. Results offer the potential to ground a bottom‐up definition of the blue economy. In so doing, this paper provides a clearly identifiable rubric of the key geographical concepts that are often overlooked by researchers, policymakers, and practitioners when promoting economic development and technological innovation in coastal and marine environments.
Despite extensive recent research elucidating the complex relationship between ecosystem services and human wellbeing, little work has sought to understand howecosystem services contribute to wellbeing and poverty alleviation. This paper adopts concepts from the “Theory of Human Need” and the “Capability Approach” to both identify the multitude of links occurring between ecosystem services and wellbeing domains, and to understand the mechanisms through which ecosystem services contribute to wellbeing. Focus Group Discussions (N = 40) were carried out at 8 sites in Mozambique and Kenya to elicit how, why, and to what extent benefits derived from ecosystem services contribute to different wellbeing domains. Our results highlight three types of mechanisms through which ecosystem services contribute to wellbeing, monetary, use and experience. The consideration of these mechanisms can inform the development of interventions that aim to protect or improve flows of benefits to people. Firstly, interventions that support multiple types of mechanisms will likely support multiple domains of wellbeing. Secondly, overemphasising certain types of mechanism over others could lead to negative social feedbacks, threatening the future flows of ecosystem services. Finally, the three mechanism types are interlinked and can act synergistically to enhance the capacities of individuals to convert ecosystem services to wellbeing.
It is critical to understand how abiotic factors may interact to constrain the distribution and productivity of marine flora and fauna in order to make robust projections of the impacts of climate change. We evaluated the effects of projected near-future ocean acidification (OA) and warming (OW) on the thermal tolerance of an important living marine resource, the sea urchin Loxechinus albus, a benthic shallow water coastal herbivore inhabiting part of the Pacific coast of South America. After exposing young juveniles for a medium-term period (1-month) to contrasting pCO2 (~500 and 1400 μatm) and temperature (~15 and 20 °C) levels, critical thermal maximum (CTmax) and minimum (CTmin) as well as thermal tolerance polygons were assessed based on self-righting success as an end point. Transcription of heat shock protein 70 (HSP70), a chaperone protecting cellular proteins from environmental stress, was also measured. Exposure to elevated pCO2significantly reduced thermal tolerance by increasing CTmin at both rearing temperatures and decreasing CTmax at 20 °C. There was also a strong synergistic effect of OA × OW on HSP70 transcription levels which were 75-fold higher than in control conditions. If this species is unable to adapt to elevated pCO2 in the future, the reduction in thermal tolerance and HSP response suggests that near-future warming and OA will disrupt their performance and reduce their distribution with ecological and economic consequences. Given the wider latitudinal range (6 to 56°S) and environmental tolerance of L. albus compared to other members of this region's benthic invertebrate community, OW and OA may cause substantial changes to the coastal fauna along the Chilean coast.
Due to the recent rapid increase in human activity and economic development, many coastal areas have recently experienced a high degree of land-based pollution. Evaluating the total maximum allocated load (TMAL) of dissolved inorganic nitrogen (DIN) nutrients and the remaining capacity is of importance for improving water quality. A considerable amount of nutrients derived from the coastal watershed can be found in wet seasons, which is non-negligible for the estimation of remaining capacity. Therefore, we use a watershed–coastal ocean coupled model combined with an optimization algorithm to tackle this issue. In contrast with previous studies, this study provides a method to estimate the spatiotemporal variations in TMALs and we then compare it to the current DIN nutrient load, including both point sources and non-point sources. Our results suggest that the TMAL of Daya Bay (DB), which is located in the northern part of the South China Sea, is about 7976 metric tons per year (t/yr) and ranges from 191 metric tons per month (t/month) to 1072 t/month. The increase of non-point source (NPS) DIN input also plays an important role in daily overload events during wet seasons. Moreover, the TMALs show an inverse exponential correlation with the water age, but only about 65% of the variance is explained. This suggests that the variations from the optimization algorithm and from local water function zoning plans are also important. According to our prediction of the DIN input, the TMAL of DB will soon be exhausted in the next several years. Consequently, prompt actions are necessary to consider the distribution of TMALs in urban developments and to decelerate the rapid growth of DIN input. Therefore, the results of this study will be helpful for both local pollution control and future urban planning.
- Marine Protected Areas (MPAs) are being implemented worldwide, yet there are few cases where managers make specific predictions of the response of previously harvested populations to MPA implementation.
- Such predictions are needed to evaluate whether MPAs are working as expected, and if not, why. This evaluation is necessary to perform adaptive management, identifying whether and when adjustments to management might be necessary to achieve MPA goals.
- Using monitoring data and population models, we quantified expected responses of targeted species to MPA implementation and compared them to monitoring data.
- The model required two factors to explain observed responses in MPAs: (a) pre‐MPA harvest rates, which can vary at local spatial scales, and (b) recruitment variability before and after MPA establishment. Low recruitment years before MPA establishment in our study system drove deviations from expected equilibrium population size distributions and introduced an additional time lag to response detectability.
- Synthesis and applications. We combined monitoring data and population models to show how (a) harvest rates prior to Marine Protected Area (MPA) implementation, (b) variability in recruitment, and (c) initial population size structure determine whether a response to MPA establishment is detectable. Pre‐MPA harvest rates across MPAs plays a large role in MPA response detectability, demonstrating the importance of measuring this poorly known parameter. While an intuitive expectation is for response detectability to depend on recruitment variability and stochasticity in population trajectories after MPA establishment, we address the overlooked role of recruitment variability before MPA establishment, which alters the size structure at the time of MPA establishment. These factors provide MPA practitioners with reasons whether or not MPAs may lead to responses of targeted species. Our overall approach provides a framework for a critical step of adaptive management.
In the last few winters, shark communities have been aggregating near the Israeli Mediterranean coast, at a specific point, near Hadera power station. This unusual phenomenon has fascinated residents, visitors, kayakers, divers, and swimmers. We analyse the effects of this intense human interest on the sharks, using contingent behaviour, in Hadera and in Ashkelon, where sharks are present and there is available infrastructure for their observation. We also report on changes in shark behaviour due to change in tourism intensity. We find a change of about ILS 4.1 million annually for both sites but a larger individual consumer surplus in Hadera, where sharks are currently observable. Touristic intensity crosses the threshold level by about 12% and making the socio-equilibrium sustainable for both humans and sharks would have a social cost of ILS 0.157 million. This paper, which is based on the assessment of conservation values to marine and coastal tourists, raises a need for spatial planning in order to protect this endangered species.