Human use and degradation of coastal ecosystems is at an all-time high. Thus, a current challenge for environmental management and research is moving beyond ecological definitions of success and integrating socioeconomic factors. Projects and studies with this aim, however, have focused primarily on monetary valuations of ecosystem functions, overlooking the behaviors and psycho-social motivations of environmental management. Using a nature-based salt marsh restoration project on Martha's Vineyard, Massachusetts, we assess the role of human attitudes and preferences in evaluating social success for ecosystem management. We use structural equation modeling to compare the strengths of social variables in predicting restoration project support, and find public understanding to be a more important predictor than personal values. Our results show that even among stakeholders with strong pro-environmental values, a weak understanding of the management initiative can undermine support. We also find that project support does not necessarily translate to the prioritization of similar management strategies. Instead, when individuals consider overall management priorities, differences arise between particular resource user-groups. This suggests that strong public support for individual initiatives can misconstrue complexities in stakeholder preferences that emerge in more comprehensive management considerations. Future investigations of the psycho-social components of management solutions should address the potentially tiered nature of human preferences, as well as whether public perceptions of management effectiveness act as an additional context-dependency of social viability.
In most small-scale fisheries, especially in developing countries, the collection of reliable fishing statistics is not regular, hampering traditional stock assessments. In those data-poor fisheries, a precise knowledge of resources co-occurrence at the ecosystem level, as well as the spatial mapping of fishing activities seem key to support management in a complex fishers-environment context. In the largest South Atlantic coralline reef, the Abrolhos Bank, fisheries are extremely diverse in terms of exploitation capacity, fishing gears, target stocks and operating areas, but any regional fisheries management is currently in place. The aim of this study was to assess, organize, and analyze fisheries of three snappers (Lutjanus jocu, L. synagris and Ocyurus chrysurus), and three groupers (Cephalopholis fulva, Epinephelus morio and Mycteroperca bonaci) along the Abrolhos Bank, with an ultimate goal of proposing useful management units. Surveys were conducted in the main fishing ports, including fishers' interviews and fish size measures in landings. Data analysis allowed a precise fishing characterization, a grouping of stocks co-occurrence, and the mapping of fishing spots and grounds. Three stocks and seven fishing areas clusters were obtained and defined statistically, suggesting useful management units. Specific fishers' groups per fleet were identified as the main stakeholders to be consulted in fisheries plans. Spatial units based on the occurrence of snappers and groupers stocks were defined, having the “Parcel das Paredes” the greatest number of fishing spots and the lower fish sizes. Overall, findings contain unprecedented fine scale resolution units that clarifies and simplifies the connections among species, fleets, fishing areas and fishers. They should also strength the call for action to implement fisheries management in a broader ecosystem-scale context.
Microplastics are highly bioavailable to marine organisms, either through direct ingestion, or indirectly by trophic transfer from contaminated prey. The latter has been observed for low-trophic level organisms in laboratory conditions, yet empirical evidence in high trophic-level taxa is lacking. In natura studies face difficulties when dealing with contamination and differentiating between directly and indirectly ingested microplastics. The ethical constraints of subjecting large organisms, such as marine mammals, to laboratory investigations hinder the resolution of these limitations. Here, these issues were resolved by analysing sub-samples of scat from captive grey seals (Halichoerus grypus) and whole digestive tracts of the wild-caught Atlantic mackerel (Scomber scombrus) they are fed upon. An enzymatic digestion protocol was employed to remove excess organic material and facilitate visual detection of synthetic particles without damaging them. Polymer type was confirmed using Fourier-Transform Infrared (FTIR) spectroscopy. Extensive contamination control measures were implemented throughout. Approximately half of scat subsamples (48%; n = 15) and a third of fish (32%; n = 10) contained 1–4 microplastics. Particles were mainly black, clear, red and blue in colour. Mean lengths were 1.5 mm and 2 mm in scats and fish respectively. Ethylene propylene was the most frequently detected polymer type in both. Our findings suggest trophic transfer represents an indirect, yet potentially major, pathway of microplastic ingestion for any species whose feeding ecology involves the consumption of whole prey, including humans.
Loliginid squids constitute marine resources of increasing importance in shelf ecosystems off the coast of South Brazil. However, the existing information and knowledge about the occurrence of early-life stages and causes of distributional patterns are insufficient. Here, we have revisited Brazilian historical plankton samples obtained from 11 oceanographic surveys to identify paralarvae and their abundances over time. The study area and time period cover the region between Cabo de São Tomé (22°S) and Cananéia (25°S) at depths down to 200 m from 1991 to 2005. Of the 246 paralarvae quantified, ~50% were identified to the genus or species level, including Doryteuthis spp. (D. sanpaulensis and D. plei), Lolliguncula brevis and a single specimen of Pickfordiateuthis pulchella. Paralarval occurrence and abundance peaked in different areas and were associated with distinct oceanographic conditions: D. sanpaulensis occurred in the northern region associated with cold waters and upwelling events, D. plei occurred primarily in the southern region of the study area and in warmer waters, and L. brevis was found in shallow and low salinity waters in the estuarine region off the coast of Santos. Overall, the highest abundance of paralarvae occurred in the nearshore, northernmost areas during summer, and this can be associated with the observed retention mechanisms caused by local circulation, seasonal upwelling, the intrusion of nutrient-rich waters, and spawning peaks. The present study provides new information and evidence for loliginid patterns in the area that may potentially be useful for better understanding the recruitment patterns and fishery assessments of squid populations.
In this chapter we discuss the potential effects of climate change on Brazilian marine fisheries and aquaculture, a sector of significant national importance, exploring the projections from global models to that particular area of the South Atlantic Ocean, changes in the level and composition of fisheries production, physical alterations affecting fishing communities, main drivers of climatic variability, and changes upon marine and brackish aquaculture. In terms of the fisheries social–ecological systems, the potential impacts of ocean warming, sea level rise, changes in ocean circulation, stratification and acidity, and extreme events, are identified for both the natural and social sub-systems. The effect of El Niño Southern Oscillation is illustrated by a particular case study in Southern Brazil, where both impacted shrimp and mullet fisheries have been generating economic losses of more than US$7.5 million per year. In terms of aquaculture production, the effects of sea level rise, temperature shifts, rainfall, floods, water stress, algal blooms, acidification, El Niño/La Niña, and indirect climatic effects are explored for the Southern and Northern coasts of Brazil. Climate change poses additional challenges to the management of marine seafood production, potentially impacting living resources, communities, post-harvest sector and consumer market. This overview contributes to the evaluation of vulnerability, adaptation options, and much-needed actions, including interdisciplinary research. The need for different precautionary and remediation strategies to minimize losses and adapt to expected events is highlighted, while spatial issues and diversification are essential in assisting adaptation to potential forthcoming environmental stress.
Coastal fishing communities are closely linked to the biological and ecological characteristics of exploited resources and the physical conditions associated with climate and ocean dynamics. Thus, the human populations that depend on fisheries are inherently exposed to climate variability and uncertainty. This study applied an ethno-oceanographic framework to investigate the perceptions of fishers on climate and ocean change to better understand the impacts of climate change on the coastal fishing communities of the South Brazil Bight. Seven coastal fishing communities that cover the regional diversity of the area were selected. Fishers were interviewed using a semi-structured questionnaire. The results suggest that fishers have detected climate-related changes in their environment such as reduced rainfall, increased drought events, calmer sea conditions, increases in air and ocean temperatures, changes in wind patterns and shoreline erosion. The perceptions of the fishers were compared to the available scientific data, and correlations were found with rainfall, wind speed and air and ocean temperatures. New hypotheses were raised based on the perceptions of fishers about sea level, coastal currents and sea conditions such as the hypothesis that the sea has become calmer. These perceived changes have positive and negative effects on the yields and livelihoods of fishers. The present work is the first evaluation of the perceptions of fishers on climate and ocean change and brings new understandings of climate-fishery-human interactions as well as provides inputs for future adaptation plans.
The canopies and roots of seagrass, mangrove, and saltmarsh protect a legacy of buried sedimentary organic carbon from resuspension and remineralisation. This legacy’s value, in terms of mitigating anthropogenic emissions of CO2, is based on total organic carbon (TOC) inventories to a depth likely to be disturbed. However, failure to subtract allochthonous recalcitrant carbon overvalues the storage service. Simply put, burial of oxidation-resistant organics formed outside of the ecosystem provides no additional protection from remineralisation. Here, we assess whether black carbon (BC), an allochthonous and recalcitrant form of organic carbon, is contributing to a significant overestimation of blue carbon stocks. To test this supposition, BC and TOC contents were measured in different types of seagrass and mangrove sediment cores across tropical and temperate regimes, with different histories of air pollution and fire together with a reanalysis of published data from a subtropical system. The results suggest current carbon stock estimates are positively biased, particularly for low-organic-content sandy seagrass environs, by 18 ± 3% (±95% confidence interval) and 43 ± 21% (±95% CI) for the temperate and tropical regions respectively. The higher BC fractions appear to originate from atmospheric deposition and substantially enrich the relatively low TOC fraction within these environs.
Coastal ecosystems provide a number of life-sustaining services, from which benefits to humans can be derived. They are often inhabited by aquatic vegetation, such as mangroves, sea grasses and salt marshes. Given their wide geographic distribution and coverage, there is need to prioritize conservation efforts. An understanding of the human importance of these ecosystems can help with that prioritization. Here, we summarize a literature review of ecosystem service valuation studies. We discuss (1) the degree to which current valuation information is sufficient to prioritize blue carbon habitat conservation and restoration, (2) the relevancy of available studies, and (3) what is missing from the literature that would be needed to effectively prioritize conservation. Given the recent focus on blue carbon ecosystems in the international conservation, there are a number of areas where research on blue forest ecosystem assessment and valuation could be improved, from enhancing available methodologies to increasing valuation of rarely studied ecosystem services and wider geographic coverage of valuation studies. This review highlights these gaps and calls for a focus on broadening the ecosystem services that are valued, the methods used, and increasing valuation in underrepresented regions.
Since the discovery of hydrothermal vents 40-years ago, long-term time-series have focused on mid-ocean ridge systems. Based on these studies, hydrothermal vents are widely considered to be dynamic, ephemeral habitats. Under this premise, national, and international regulatory bodies are currently planning for the commercial mining of polymetallic sulfide deposits from hydrothermal vents. However, here we provide evidence of longevity and habitat stability that does not align with historic generalizations. Over a 10-year time-series focused on the back-arc basin systems off the west coast of the Kingdom of Tonga (South Pacific), we find the hydrothermal vents are remarkably stable habitats. Using high-resolution photo mosaics and spatially explicit in situ measurements to document natural changes of five hydrothermal vent edifices, we discovered striking stability in the vent structures themselves, as well as in the composition and coverage of the vent-associated species, with some evidence of microdistribution permanence. These findings challenge the way we think about hydrothermal vent ecosystems and their vulnerability and resilience to deep-sea mining activities.
Species inhabiting deep-sea hydrothermal vents are strongly influenced by the geological setting, as it provides the chemical-rich fluids supporting the food web, creates the patchwork of seafloor habitat, and generates catastrophic disturbances that can eradicate entire communities. The patches of vent habitat host a network of communities (a metacommunity) connected by dispersal of planktonic larvae. The dynamics of the metacommunity are influenced not only by birth rates, death rates and interactions of populations at the local site, but also by regional influences on dispersal from different sites. The connections to other communities provide a mechanism for dynamics at a local site to affect features of the regional biota. In this paper, we explore the challenges and potential benefits of applying metacommunity theory to vent communities, with a particular focus on effects of disturbance. We synthesize field observations to inform models and identify data gaps that need to be addressed to answer key questions including: (1) what is the influence of the magnitude and rate of disturbance on ecological attributes, such as time to extinction or resilience in a metacommunity; (2) what interactions between local and regional processes control species diversity, and (3) which communities are “hot spots” of key ecological significance. We conclude by assessing our ability to evaluate resilience of vent metacommunities to human disturbance (e.g., deep-sea mining). Although the resilience of a few highly disturbed vent systems in the eastern Pacific has been quantified, these values cannot be generalized to remote locales in the western Pacific or mid Atlantic where disturbance rates are different and information on local controls is missing.
The objective of this issue of «Science for MPA Management» is to explore the process of the ecosystem approach adopted in 2008 by the Contracting Parties to the Barcelona Convention and the Marine Strategy Framework Directive of the European Union. In this context, Mediterranean Marine Protected Areas (MPAs) are identified as a key element in the implementation of monitoring that aims to report on the progress made towards the achievement of the Good Environmental Status of the Mediterranean. Their role must nevertheless be strengthened, with in particular a potential support from the MedPAN network to coordinate monitoring in MPAs on different components related to the EcAP process on a Mediterranean scale.
The bias in catch time series data that occurs when improvements in fisheries catch reporting systems (e.g., consideration of a previously unmonitored fishery, or region) lead to an increase in current catches without the corresponding past catches being corrected retroactively, here called ‘presentist bias’ is described, and two examples, pertaining to Mozambique and Tanzania are given. This bias has the effect of generating catch time series at the aggregate that appear ‘stable’ or increasing when in fact catches are declining over time, with potentially serious consequences for the assessment of the status of national fisheries, or in interpreting the global landings data disseminated by the FAO. The presentist bias can be compensated for by retroactive national data corrections as done, e.g., through catch reconstructions.
Ecological theory suggests that large-scale patterns such as community stability can be influenced by changes in interspecific interactions that arise from the behavioural and/or physiological responses of individual species varying over time1,2,3. Although this theory has experimental support2,4,5, evidence from natural ecosystems is lacking owing to the challenges of tracking rapid changes in interspecific interactions (known to occur on timescales much shorter than a generation time)6and then identifying the effect of such changes on large-scale community dynamics. Here, using tools for analysing nonlinear time series6,7,8,9 and a 12-year-long dataset of fortnightly collected observations on a natural marine fish community in Maizuru Bay, Japan, we show that short-term changes in interaction networks influence overall community dynamics. Among the 15 dominant species, we identify 14 interspecific interactions to construct a dynamic interaction network. We show that the strengths, and even types, of interactions change with time; we also develop a time-varying stability measure based on local Lyapunov stability for attractor dynamics in non-equilibrium nonlinear systems. We use this dynamic stability measure to examine the link between the time-varying interaction network and community stability. We find seasonal patterns in dynamic stability for this fish community that broadly support expectations of current ecological theory. Specifically, the dominance of weak interactions and higher species diversity during summer months are associated with higher dynamic stability and smaller population fluctuations. We suggest that interspecific interactions, community network structure and community stability are dynamic properties, and that linking fluctuating interaction networks to community-level dynamic properties is key to understanding the maintenance of ecological communities in nature.
Here, we report trading of endangered shark species in a world hotspot for elasmobranch conservation in Brazil. Data on shark fisheries are scarce in Brazil, although the northern and northeastern regions have the highest indices of shark bycatch. Harvest is made primarily with processed carcasses lacking head and fins, which hampers reliable species identification and law enforcement on illegal catches. We used partial sequences of two mitochondrial genes (COI and/or NADH2) to identify 17 shark species from 427 samples being harvested and marketed on the northern coast of Brazil. Nine species (53%) are listed under some extinction threat category according to Brazilian law and international authorities (IUCN – International Union for Conservation of Nature; CITES – Convention on International Trade of Endangered Species of Wild Fauna and Flora). The number increases to 13 (76%) if we also consider the Near Threatened category. Hammerhead sharks are under threat worldwide, and composed 18.7% of samples, with Sphyrna mokarran being the fourth most common species among samples. As illegal trade of threatened shark species is a worldwide conservation problem, molecular identification of processed meat or specimens lacking diagnostic body parts is a highly effective tool for species identification and law enforcement.
Shipping is the dominant marine anthropogenic noise source in the world's oceans, yet we know little about vessel encounter rates, exposure levels and behavioural reactions for cetaceans in the wild, many of which rely on sound for foraging, communication and social interactions. Here, we used animal-borne acoustic tags to measure vessel noise exposure and foraging efforts in seven harbour porpoises in highly trafficked coastal waters. Tagged porpoises encountered vessel noise 17–89% of the time and occasional high-noise levels coincided with vigorous fluking, bottom diving, interrupted foraging and even cessation of echolocation, leading to significantly fewer prey capture attempts at received levels greater than 96 dB re 1 µPa (16 kHz third-octave). If such exposures occur frequently, porpoises, which have high metabolic requirements, may be unable to compensate energetically with negative long-term fitness consequences. That shipping noise disrupts foraging in the high-frequency-hearing porpoise raises concerns that other toothed whale species may also be affected.
Synchronised multispecies mass spawning events are striking features of reproduction in corals. This synchronous gamete release of thousands of animals over vast stretches of reef is thought to be cued by rhythms of the Moon. However, the mechanisms are not fully understood. We propose an explanation that may contribute to understanding this mechanism, that spawning is triggered by the coincidence of two factors, each in different lunar rhythms. We investigate this proposal in case studies using seven years of coral spawning data from two locations: Kochi, Japan and Lizard Island, Australia. Our calculations show that a feature in a lunar synodic rhythm (the third quarter) will synchronise with a feature in a lunar non-synodic rhythm (the zero declination) usually once, although occasionally twice in a year. Supported by data on the date of spawning from the two locations, we suggest that this coincidence of lunar factors exerts an important influence on the timing of annual mass spawning in corals. This coincidence may be associated with low atmospheric pressure. Spawning at the time of the third lunar quarter may favour fertilisation success due to the reduced currents during neap tides associated with the lower gravitational pressure of the lunar quarters.
Fishing Reserves (FRs) are primarily designated for the enhancement of local fisheries and, secondarily, for biodiversity conservation. In Spain, FRs are considered marine protected areas (MPAs) and included in the country's MPA network. MPAs’ ecological effectiveness is linked to a number of legal, managerial and bio-physical factors. With the amount of MPA area rapidly rising and conservation funds largely stagnant or decreasing, rapid, cost-effective MPA assessment techniques are becoming increasingly useful to verify fulfillment of global conservation targets and ascertain potential conservation effectiveness. Here, a rapid MPA protection assessment framework and one MPA ecological effectiveness framework were applied to the Spanish Network of 10 FRs (FRN): the MaPAF and NEOLI frameworks. The FRN was moderately legally protected, with over 50.5% of its area having three or more overlapping legal designations, but only 3.8% of the FRN's area being no-take. All FRs had management plans and active surveillance. According to MaPAF, Columbretes FR was the most highly legally protected whereas Cabo de Palos was the FR with the greatest managerial effort. Both rank highest in protection. In contrast, Masía Blanca FR and Alborán FR were the least legally protected whereas Alborán FR and Graciosa FR were the least managerially protected FRs of the FRN and rank the lowest in protection, respectively. According to the NEOLI framework, Columbretes would also be the most effective FR whereas Masía Blanca FR would be the least ecologically effective. These results can help to spur and better allocate conservation efforts across the fastly growing Spanish MPA network.
Ship’s ballast water has been a vector for the spreading of nonindigenous invasive species (NIS) around the globe for more than a century and has had devastating impact on aquatic ecosystems in many regions. Due to the harsh climate, shipping activities in Arctic waters have been limited compared to many parts of the world but will increase in the coming years due to climate changes. This will potentially affect the pristine Arctic marine ecosystems by introduction of NIS. In this chapter, we present the international ballast water regulations that have entered into force and the specific challenges of ballast water management in relation to the Arctic environment and marine ecosystems. We discuss the risk of NIS affecting the Arctic marine ecosystems including the impact of increased shipping activity, changes in living conditions of marine organisms because of climate changes and lack of knowledge of the eco-physiological boundaries and distributions of Arctic marine species. It is concluded that at present only a few marine NIS have been recorded in the Arctic area. Despite the existing and planned ballast water regulations, NIS establishment in the region will increase with an unknown magnitude due to lack of biological data.
The Arctic has been an integrated part of the international system for centuries, and systemic developments have deeply influenced the region and its communities. Central Arctic Ocean marine resource governance is in the nexus of climate change and international systemic developments. The international systemic context for the Arctic is: The rise of China and emerging Asian economies driving gradual power transition from Western to Eastern states. Struggles continue over the domestic order and international position of post-Soviet Russia, where either side considers whether to escalate the Ukraine crisis horizontally to the Arctic. The USA and China interact concerning governing Arctic marine resources as Arctic Ocean coastal state/status quo power and fishing nation/rising power. Russia and the West choose not to escalate the Ukraine crisis horizontally into Arctic marine resource management. Co-creating of knowledge and epistemic communities are important for Arctic status quo and rising Asian countries to manage power transition in the Arctic and for Russia and the West to continue Arctic cooperation despite political crisis elsewhere.
Future estimates indicate that the reduction of the Arctic ice cap will open up new areas and increase the viability of the region to be increasingly used for international shipping (Liu and Kronbak, J Trans Geo 18(3):434–444. doi:https://doi.org/10.1016/j.jtrangeo.2009.08.004, 2010). The Arctic sea routes and related coastal area are therefore gaining increasing levels of interest, as they become a more attractive alternative for maritime transport. This demand for new infrastructure and development in areas where there has previously been little or none, presents a unique situation to analyze. The increased interest and demand for new development along Arctic sea routes through an environmentally sensitive region make the Arctic an ideal area of which to study the transition toward liquefied natural gas becoming the prominent marine fuel.
We must develop a better understanding of how and under what conditions such a transition will take place and who will make decisions that will influence any such transition. Exploring past and current aspects of maritime and energy governance is an important step in developing an understanding of how a transition towards liquefied natural gas could re-shape our understanding of Arctic governance.