Marine Protected Areas (MPAs) are a common tool for conserving and managing marine and coastal ecosystems. MPAs encompass a range of protection levels, from fully protected areas (FPAs) to partially protected areas (PPAs), with restriction of particular activities, gear types or user groups. There is a growing body of scientific evidence supporting the ecological benefits of FPAs, but it is very difficult to generalize about the effects of partial protection, due to their high variability. However, it is critical to determine whether PPAs and FPAs provide similar ecological benefits, since the establishment of FPAs is in some situations a less popular strategy, due to the loss of fishing grounds and local sociopolitical antagonism. For the purpose of conducting a meta-analysis, we synthesized peer-reviewed studies comparing biological measures (biomass and density) of commercially targeted fish species in PPAs relative to FPAs and open access areas (OAs) across the tropical seas, resulting in a database of 33 PPAs. A new categorization scheme was used to group the different types of PPAs according to the extractive activities permitted within their boundaries, into three categories: highly regulated PPAs, moderately regulated PPAs, and weakly and very weakly regulated PPAs. The response to protection was examined in relation to PPA category, age and size. The present synthesis indicates that, overall, tropical PPAs generate greater biological responses in the biomass of targeted fish compared to OAs and demonstrate no significant differences when compared to FPAs. Grouping the PPAs according to uses allowed revealed that areas with highly regulated extraction exhibit greater biomass of targeted fish relative to areas with weakly regulated categories. The density of the targeted fish species did not demonstrate a response to the different protection regimes as strong as the biomass did. Although there was a high degree of variability in the magnitude of responses to protection, the age and size of the PPAs explained some of this variability. Overall, PPAs with limited and well regulated extraction activities may confer benefits and be a valuable conservation management option, especially, in areas where FPAs are not a viable option or in multi-zoning MPAs.
This study delves into the development of a Geographic Information System (GIS) based vulnerability assessment tool for assessing coastal vulnerability and making prescriptive recommendations on urban planning in coastal regions at a local level. The framework of “exposure-sensitivity-resilience” (ESR) is not only applied, but also improved and refined to take into account a suite of social-ecological indicators. The results demonstrate that vulnerability was not evenly distributed across Haikou's coastal zones, which may be linked to the different stages of ongoing urban planning for coastal Haikou. For the case study areas, vulnerability tends to increase with higher levels of urbanization, but may decrease once the speed of urban expansion is under control. The most vulnerable area is the main city zone where urban residents are concentrated and a developed transportation network exists. Our study contributes to the development of a general methodology to assess vulnerability in rapid urbanization and to apply it to coastal cities around the world.
Mining of seafloor massive sulfides (SMS) is imminent, but the ecology of assemblages at SMS deposits is poorly known. Proposed conservation strategies include protected areas to preserve biodiversity at risk from mining impacts. Determining site suitability requires biological characterisation of the mine site and protected area(s). Video survey of a proposed mine site and protected area off New Zealand revealed unique megafaunal assemblages at the mine site. Significant relationships were identified between assemblage structure and environmental conditions, including hydrothermal features. Unique assemblages occurred at both active and inactive chimneys and are particularly at risk from mining-related impacts. The occurrence of unique assemblages at the mine site suggests that the proposed protected area is insufficient alone and should instead form part of a network. These results provide support for including hydrothermally active and inactive features within networks of protected areas and emphasise the need for quantitative survey data of proposed sites.
Bycatch of non-target species in commercial fisheries is a major source of anthropogenic injury and mortality for marine megafauna, including marine turtles. Their long life histories and large-scale habitat use increase the risk of interaction with multiple fleets and gear types, with consequences for population decline or collapse. However, assessment of bycatch species rarely extends beyond a single-fishery management approach, without considering the impacts of additional bycatch incurred in other fisheries. To demonstrate the need for cross-jurisdictional assessment of turtle bycatch, we evaluate the cumulative patterns of turtle bycatch in Australian commercial fisheries. We sourced logbook bycatch records from multiple fisheries in three separate management jurisdictions over the period 2000–2013. The highest bycatch per unit effort values were reported in pelagic gillnets, otter trawls and pelagic longlines. Spatial analysis revealed a bycatch ‘hotspot’ in the Gulf of Carpentaria, where commercial fisheries impact multiple turtle species and genetic stocks. Our results illustrate the need to set cumulative bycatch quotas for marine turtles, and to evaluate turtle bycatch at the population level instead of separately within individual fisheries. We stress the need for timely collaboration between management agencies in order to implement effective, biologically relevant management strategies for marine turtles and other vulnerable taxa.
Trophic magnification factors (TMFs) are field-based measurements of the bioaccumulation behavior of chemicals in food-webs. TMFs can provide valuable insights into the bioaccumulation behavior of chemicals. However, bioaccumulation metrics such as TMF may be subject to considerable uncertainty as a consequence of systematic bias and the influence of confounding variables. This study seeks to investigate the role of systematic bias resulting from spatially-variable concentrations in water and sediments and biotransformation rates on the determination of TMF. For this purpose, a multibox food-web bioaccumulation model was developed to account for spatial concentration differences and movement of organisms on chemical concentrations in aquatic biota and TMFs. Model calculated and reported field TMFs showed good agreement for persistent polychlorinated biphenyl (PCB) congeners and biotransformable phthalate esters (PEs) in a marine aquatic food-web. Model testing showed no systematic bias and good precision in the estimation of the TMF for PCB congeners but an apparent underestimation of model calculated TMFs, relative to reported field TMFs, for PEs. A model sensitivity analysis showed that sampling designs that ignore the presence of concentration gradients may cause systematically biased and misleading TMF values. The model demonstrates that field TMFs are most sensitive to concentration gradients and species migration patterns for substances that are subject to a low degree of biomagnification or trophic dilution. The model is useful in anticipating the effect of spatial concentration gradients on the determination of the TMF; guiding species collection strategies in TMF studies; and interpretation of the results of field bioaccumulation studies in study locations where spatial differences in chemical concentration exist.
Ecosystem services have a significant impact on human wellbeing. While ecosystem services are frequently represented by monetary values, social values and underlying social benefits remain underexplored. The purpose of this study is to assess whether and how social benefits have been explicitly addressed within socio-economic and socio-cultural ecosystem services research, ultimately allowing a better understanding between ecosystem services and human well-being. In this paper, we reviewed 115 international primary valuation studies and tested four hypotheses associated to the identification of social benefits of ecosystem services using logistic regressions. Tested hypotheses were that (1) social benefits are mostly derived in studies that assess cultural ecosystem services as opposed to other ecosystem service types, (2) there is a pattern of social benefits and certain cultural ecosystem services assessed simultaneously, (3) monetary valuation techniques go beyond expressing monetary values and convey social benefits, and (4) directly addressing stakeholdeŕs views the consideration of social benefits in ecosystem service assessments. Our analysis revealed that (1) a variety of social benefits are valued in studies that assess either of the four ecosystem service types, (2) certain social benefits are likely to co-occur in combination with certain cultural ecosystem services, (3) of the studies that employed monetary valuation techniques, simulated market approaches overlapped most frequently with the assessment of social benefits and (4) studies that directly incorporate stakeholder's views were more likely to also assess social benefits.
Runoff from human land-uses is one of the most significant threats to some coastal marine environments. Initiatives to reduce that runoff usually set runoff reduction targets but do not give guidance on how to prioritize the different options that exist to achieve them. This paper demonstrates an easy to interpret economic framework to prioritise investment for conservation projects that aim to reduce pollution of marine ecosystems caused by runoff from agricultural land-uses. We demonstrate how to apply this framework using data on project cost, benefit and feasibility with a subset of projects that have been funded to reduce runoff from subcatchments adjacent to the Great Barrier Reef. Our analysis provides a graphical overview of the cost-effectiveness of the investment options, enables transparent planning for different budgets, assesses the existence of trends in the cost-effectiveness of different categories, and can test if the results are robust under uncertainty in one or more of the parameters. The framework provided solutions that were up to 4 times more efficient than when omitting information on cost or benefit. The presented framework can be used as a benchmark for evaluating results from a range of prioritisation processes against the best possible conservation outcomes.
Sea-level rise due to climate change creates new risks of submersion in coastal areas that must be taken into account. Although these are long-term risks for 2100, it is important to anticipate possible consequences in order to identify the most vulnerable areas or issues and develop the appropriate adaptation policies. The aim of this paper is to examine the consequences of such sea-level rise for wetlands in the Languedoc-Roussillon region (France) which is particularly at risk of submersion. The analysis is based on the worst case scenario of a one meter sea level rise by 2100, with a variety of adaptive strategies: denial, laissez-faire and strategic retreat of infrastructure and buildings. This latter strategy assumes that the retreat wetlands is unconstrained. The evaluation examines the losses and transformations of ecological habitats, depending on their distance from salt water. Estimating damages and benefits requires first, to study the evolution of the services supplied by different habitats and second, to estimate the value of the economic impact. This approach demonstrates the superiority of a strategic retreat policy which would halve the damages resulting from submersion.
Multi-objective evolutionary algorithms (MOEAs) are becoming increasingly popular for solving formal environmental and water resources optimisation problems. In the past, the focus of these studies has generally been on methodological issues related to the optimisation algorithm. However, in recent years, there has been increased recognition of the need to apply these approaches to real-world problems to facilitate the realisation of their full potential. In order to assist with this, a framework for including stakeholder input in real-world optimisation problems is introduced in this paper, including a conceptual framework and a procedure for implementing it. The framework is applied to an urban water supply security study for Adelaide, South Australia. This study highlights the role of stakeholder input at the various stages of the optimisation process, as well as the resulting changes in the formulation, analysis and results. A discussion of the lessons learnt from the case study is also provided.
The primary role of marine protected areas (MPAs) is marine conservation, however policy and practice around MPAs have not reflected this. The focus on cost-effectiveness by spatial conservation prioritization has led to a bias towards placing MPAs in areas that are least threatened. This study investigates how conservation priorities differ between two management strategies of either targeting or avoiding high threat areas for protection, using the case of the Sulu Sulawesi Seas in the Coral Triangle. For both strategies, the target of protecting 20% of habitat could not be achieved solely by protecting low threat areas. A high proportion of the region had large differences in conservation outcomes between the two strategies; majority of these areas were highly prioritized in the threat avoidance strategy but had low or zero importance in the threat selection strategy. Selecting for highly threatened areas required less habitat area to be protected to achieve the same conservation target and resulted in a more equitable distribution of priority sites per country and sub-region. This demonstrates the importance of deciding on the objectives of conservation and management policies up-front. The results suggest that, contrary to the common practice of avoiding threats in spatial planning, a threat selection strategy should be part of the management toolbox, particularly in transboundary planning for regions with high overall threat levels, where it may be important to achieve shared conservation targets equitably.