Coral reefs experiencing ocean acidification (OA) are likely to recover much more slowly from damage caused by acute events such as mass bleaching because OA slows coral reef growth and reproduction. To maintain reefs in a net growth or net-neutral condition, curbing the impact of OA is therefore necessary. A variety of mitigation and adaptation strategies have been proposed to abate OA impacts on reefs. However, detailed guidance for managers on the types, effectiveness, or costs of different local interventions to address OA is scarce. To advance the discussion about available interventions, this review explores and compares mitigation and adaptation techniques that have been proposed to abate OA impacts on coral reefs. We focus primarily on four categories of interventions intended to address different ecosystem service changes: phytoremediation, chemical remediation, reef restoration, and assisted evolution. We briefly touch on traditional restoration methods like marine protected areas (MPAs) and reducing secondary sources of stress. Of the techniques reviewed, most are costly and do not scale at the same pace as global reef loss. Nor do they address the root cause of OA, global carbon emissions. That said, intervention should not be an all or nothing approach; some techniques may be worth implementing at smaller scales in a coordinated way. Working to save pieces of ecosystems and buying time may help ensure that there is more to rebuild from in the future. Despite the seemingly high price tag of many of these techniques, given the potential value of regained ecosystem services, net gains may exceed implementation costs. It is certain, however, from the limited reach of coral reef interventions, that they must be undertaken as part of a suite of global-scale interventions including atmospheric CO2 reduction to preserve coral reef ecosystem function and benefits to humanity.
Twitter accounts have already been used in many scientometric studies, but the meaningfulness of the data for societal impact measurements in research evaluation has been questioned. Earlier research focused on social media counts and neglected the interactive nature of the data. We explore a new network approach based on Twitter data in which we compare author keywords to hashtags as indicators of topics. We analyze the topics of tweeted publications and compare them with the topics of all publications (tweeted and not tweeted). Our exploratory study is based on a comprehensive publication set of climate change research. We are interested in whether Twitter data are able to reveal topics of public discussions which can be separated from research-focused topics. We find that the most tweeted topics regarding climate change research focus on the consequences of climate change for humans. Twitter users are interested in climate change publications which forecast effects of a changing climate on the environment and to adaptation, mitigation and management issues rather than in the methodology of climate-change research and causes of climate change. Our results indicate that publications using scientific jargon are less likely to be tweeted than publications using more general keywords. Twitter networks seem to be able to visualize public discussions about specific topics.
The effect of fiber type (cotton, polyester, and rayon), temperature, and use of detergent on the number of microfibers released during laundering of knitted fabrics were studied during accelerated laboratory washing (Launder-Ometer) and home laundering experiments. Polyester and cellulose-based fabrics all shed significant amounts of microfibers and shedding levels were increased with higher water temperature and detergent use. Cellulose-based fabrics released more microfibers (0.2–4 mg/g fabric) during accelerated laundering than polyester (0.1–1 mg/g fabric). Using well-controlled aquatic biodegradation experiments it was shown that cotton and rayon microfibers are expected to degrade in natural aquatic aerobic environments whereas polyester microfibers are expected to persist in the environment for long periods of time.
We describe an investigation into the challenges faced by fishing gear technologists inspiring the voluntary uptake of proven fishing gear by fishers, defined as fishing gear that has satisfied research objectives following field trials between fishers and fishing gear technologists. We applied a multifaceted approach to understand how the uptake rate of this fishing gear can be achieved based on the results of a 3-year ICES-FAO Working Group on Fishing Technology and Fish Behaviour (WGFTFB) topic group on change management in fisheries. This was supported by an online survey and interview of WGFTFB members, comprising mainly of fishing gear technologists and researchers from Europe and North America, and a review of projects in the US Northwest Atlantic to evaluate the performance of fishing gear in close collaboration with fishers. We found that widespread voluntary uptake of proven fishing gear by fishers is rare, and usually takes place over many years if at all. The uptake of this gear was more likely occur in the face of perceived financial benefit or impending regulation, although financial benefit was not always sufficient inducement for fishers change their gear. The effectiveness of outreach programmes to inspire the uptake of this gear was also found to be questionable, and the efficacy of incentives was limited and inconsistent, even if the informational deficit of fishers was low. Few WGFTFB members were found to use change management models such as that by Kotter, and they relied mainly on informal, ad hoc approaches to inspire the uptake of proven fishing gear. Based on our findings we posit a need to (i) examine our assumptions about the behaviour of fishers, (ii) augment communication of the results of fishing gear research, (iii) focus on emotions to overcome motivational deficits, and (iv) consider how the application of change management models can improve the ability of fishing gear technologists to inspire the uptake of proven fishing gear by fishers.
Climate-driven changes in ocean currents have facilitated the range extension of the long-spined sea urchin (Centrostephanus rodgersii) from Australia’s mainland to eastern Tasmania over recent decades. Since its arrival, destructive grazing by the urchin has led to widespread formation of sea urchin ‘barrens’. The loss of habitat, biodiversity and productivity for important commercial reef species in conjunction with the development of an urchin fishery has led to conflicting objectives among stakeholders, which poses complex challenges for regional management. Stakeholder representatives and managers were engaged via a participatory workshop and subsequent one-on-one surveys to trial a structured decision-making process to identify effective ecosystem-based management strategies. We directly and indirectly elicited each stakeholder’s preferences for nine alternative management strategies by presenting them with the 10-year consequences of each strategy estimated from an ecosystem model of Tasmanian reef communities. These preferences were included in cost-effectiveness scores that were averaged (across stakeholders) to enable strategy ranking from most to least cost-effective. Rankings revealed strategies that included sea urchin removal or translocation of predatory lobsters were the most cost-effective. However, assessment of stakeholders’ individual cost-effectiveness scores showed some disparity among stakeholders’ preferences in high ranking strategies. Additionally, evaluating inconsistencies within some stakeholders’ scores that included direct or indirect preferences revealed conflicting objectives and cognitive bias as the most plausible explanations for these inconsistencies. Our study illustrates how structured decision-making can effectively facilitate ecosystem-based management by engaging stakeholders step-by-step towards management strategy implementation, identifying psychological barriers to decision-making and promoting collective learning.
One of the current major scientific challenges to sustain social-ecological systems is to improve our understanding of the spatial and temporal dynamics of the relationships between biodiversity, ecosystem functioning and ecosystem services. Here, we analyse the bundles of ecosystem services supplied by three coastal ecosystems (coastal lagoons, coral reefs and sandy beaches) along a gradient of eutrophication. Based on a state-and-transition model, we analyses the dynamic responses of ecological communities to environmental change and management actions. Although few exceptions are highlighted, increasing eutrophication in the three ecosystem types leads to a degradation of the ecosystem service bundles, particularly for nutrient and pathogen regulation/sequestration, or for the support of recreational and leisure activities. Despite few obstacles to their full use, state-and-transition models can be very powerful frameworks to integrate multiple functions and services delivered by ecosystems while accounting for their temporal dynamics.
Regulatory discharge standards stipulating a maximum allowable number of viable organisms in ballast water have led to a need for rapid, easy and accurate compliance assessment tools and protocols. Some potential tools presume that organisms present in ballast water samples display the same characteristics of life as the native community (e.g. rates of fluorescence). This presumption may not prove true, particularly when ships' ballast tanks present a harsh environment and long transit times, negatively impacting organism health. Here, we test the accuracy of a handheld pulse amplitude modulated (PAM) fluorometer, the Hach BW680, for detecting photosynthetic protists at concentrations above or below the discharge standard (< 10 cells·ml− 1) in comparison to microscopic counts using fluoresce indiacetate as a viability probe. Testing was conducted on serial dilutions of freshwater harbour samples in the lab and in situ untreated ballast water samples originating from marine, freshwater and brackish sources utilizing three preprocessing techniques to target organisms in the size range of ≥ 10 and < 50 μm. The BW680 numeric estimates were in agreement with microscopic counts when analyzing freshly collected harbour water at all but the lowest concentrations (< 38 cells·ml− 1). Chi-square tests determined that error is not independent of preprocessing methods: using the filtrate method or unfiltered water, in addition to refining the conversion factor of raw fluorescence to cell size, can decrease the grey area where exceedance of the discharge standard cannot be measured with certainty (at least for the studied populations). When examining in situ ballast water, the BW680 detected significantly fewer viable organisms than microscopy, possibly due to factors such as organism size or ballast water age. Assuming both the BW680 and microscopy with FDA stain were measuring fluorescence and enzymatic activity/membrane integrity correctly, the observed discrepancy between methods may simply reflect that the two methods are measuring different characteristics of life. This is the first study to conduct proof-of-concept testing for a rapid compliance detection tool using freshly collected harbour water concomitantly with in situ ballast water; our results demonstrate that it is important to challenge potential compliance tools with water samples spanning a range of biotic and abiotic conditions.
Understanding spatial distributions of fish species is important to those seeking to manage fisheries and advise on marine developments. Distribution patterns, habitat use, and aggregative behaviour often vary throughout the life cycle and can increase the vulnerability of certain life stages to anthropogenic impacts. Here we investigate distribution changes during the life cycle of whiting (Merlangius merlangus) to the west of the UK. Density distributions for age-0, age-1 and mature fish were modelled as functions of environmental variables using generalised additive mixed effects models. The greatest densities of age-0 whiting occurred over finer sediments where temperatures were between 12 to 13°C. Age-0 whiting densities decreased with increasing depth. Higher densities of age-1 whiting were also associated with fine sediments and peaked at 60 m, but this influence was also dependent on proximity to shore. Mature fish, while showing no association with any particular sediment type, were strongly associated with depths >60 m. Geostatistical aggregation curves were used to classify space use and showed persistent aggregations of age-0 whiting occupying inshore waters while age-1 and mature fish were more dispersed and differed among years. The differences in distributions among life stages suggested a general coastal to offshore shift as cohorts developed with mature whiting mainly occupying deep offshore waters. The spatial dynamics and areas of persistent life stage aggregation identified here could enable informed targeting and avoidance of specific age-class whiting to aid bycatch reduction. Given that landing obligation legislation is counterproductive unless it encourages greater fishing selectivity, the ability to avoid this species and undersized individuals would aid conservation measures and fishermen alike.
Knowledge on the spatial distribution, habitat use and processes of site selection by marine turtles is fundamental to identify key habitats, critical resources, and discrete foraging aggregations for protection. This is particularly important for regions of known importance for marine turtles and where widespread habitat degradation is taking place. The waters surrounding Bimini, Bahamas, provide important foraging areas for threatened juvenile green turtles (Chelonia mydas) however, these habitats are being severely degraded by coastal development. To inform managers on the design of planned future no-take marine protected areas (MPA) in Bimini, we used a spatial planning approach and incorporated diverse methodologies (e.g., visual surveys, capture events, passive acoustic telemetry) to identify areas of high use by juvenile green turtles. We also assessed forage items to understand habitat use by green turtles. This information was compared with how various stakeholders use the local waters to identify priority areas for protection within Bimini to maximize conservation of green turtles, while minimizing impact to society, and to meet the conservation target previously stipulated by government officials. Two regions within Bimini (South Flats in south Bimini and Bonefish Hole on the north Island) were identified as important areas for protection and suggestions are made on their considerations for MPA implementation.
The application of historical perspectives and the documentation of long-term change in and views about the ocean is increasingly sought to frame and contextualize current issues facing marine science and policy. One of the important methods for informing such an historical perspective is through the use of oral histories, long used by social scientists for insight into local knowledge, lived history, and their meaning to participants. In this article, we seek to demonstrate the relevance of oral histories for understanding the changing institutional setting and research focus of marine science in the United States, and the unique platform it offers for introspective reflection on where marine sciences are today, where they have been, and where they might like to go. We discuss the influence of institutional changes on research topics, the impact of regional differences on the sciences, the increasing emphasis on mathematics and modelling, and new directions incorporating ecosystems, human communities, and public involvement. Finally, we conclude with consideration of the value of oral histories and other qualitative methods for elucidating experiences of and perspectives on the past.