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Transfer efficiency is the proportion of energy passed between nodes in food webs. It is an emergent, unitless property that is difficult to measure, and responds dynamically to environmental and ecosystem changes. Because the consequences of changes in transfer efficiency compound through ecosystems, slight variations can have large effects on food availability for top predators. Here, we review the processes controlling transfer efficiency, approaches to estimate it, and known variations across ocean biomes. Both process-level analysis and observed macroscale variations suggest that ecosystem-scale transfer efficiency is highly variable, impacted by fishing, and will decline with climate change. It is important that we more fully resolve the processes controlling transfer efficiency in models to effectively anticipate changes in marine ecosystems and fisheries resources. Transfer efficiency is a key parameter describing ecosystem structure and function and is used to estimate fisheries production; however, it is also one of the most uncertain parameters. Questions remain about how habitats, food resources, fishing pressure, spatiotemporal scales, as well as temperature, primary production, and other climate drivers impact transfer efficiency. Direct measurements of transfer efficiency are difficult, but observations of marine population abundances, diets, productivity, stable isotope analysis, and models integrating these constraints can provide transfer efficiency estimates. Recent estimates suggest that transfer efficiency is more variable than previously thought, compounding uncertainties in marine ecosystem predictions and projections. Increased understanding of factors contributing to variation in transfer efficiency will improve projections of fishing and climate change impacts on marine ecosystems. [ABSTRACT FROM AUTHOR]

Full no-take marine reserves (MRs) act as tools for biodiversity protection that reduce or remove human-induced disturbances and support the recovery of harvested species. Even if not designed specifically for fisheries management, MRs have the potential to enhance locally and distantly fished populations. This study quantified contemporary catch per unit effort (CPUE) of rock lobsters (RLs) with respect to weight and abundance inside and outside two central New Zealand MRs (Kapiti MR established in 1992, Taputeranga MR established in 2008) using commercial fishing methods (pots), and compared it to historical CPUE data. On average, mean CPUE and mean RL size were significantly greater inside than outside at both MRs. Contemporary CPUE at both MRs was approximately twice that of historical CPUE prior to the reserves being established. At Taputeranga, but not at Kapiti MR, we observed a gradient in CPUE with distance from the centre of the reserve. MRs had higher CPUE at reefs that were fully protected (entire reef in the MR) than at partially protected reefs (reef spans the MR boundary), which in turn had higher CPUE than unprotected reefs (entire reef outside the MR). Our results indicate that RL populations are responding positively to protection, but that factors such as the amount of reef area protected and proximity to reserve boundary contribute differently to RL responses. Our findings contribute to the design of MRs with respect to the habitat they protect and to a better understanding of the interactions between MRs and local fisheries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nature Futures Framework is a heiristic tool for creating positive futures for nature and people. • Nature Futures scenarios explore a mix of policies that progresses the world towards positive futures. • Reflecting diverse values and worldviews helps identify context-relevant interventions. • Mutually reinforcing positive social-ecological feedbacks can accelerate transformation pathways. • Indicators representing diverse values of nature build comprehensive evidence bases for policy. The Nature Futures Framework (NFF) is a heuristic tool for co-creating positive futures for nature and people. It seeks to open up a diversity of futures through mainly three value perspectives on nature – Nature for Nature, Nature for Society, and Nature as Culture. This paper describes how the NFF can be applied in modelling to support decision-making. First, we describe key considerations for the NFF in developing qualitative and quantitative scenarios: i) multiple value perspectives on nature as a state space where pathways improving nature toward a frontier can be represented, ii) mutually reinforcing key feedbacks of social-ecological systems that are important for nature conservation and human wellbeing, iii) indicators of multiple knowledge systems describing the evolution of complex social-ecological dynamics. We then present three approaches to modelling Nature Futures scenarios in the review, screening, and design phases of policy processes. This paper seeks to facilitate the integration of relational values of nature in models and strengthen modelled linkages across biodiversity, nature's contributions to people, and quality of life. [ABSTRACT FROM AUTHOR]

Monitoring and assessing the effectiveness of no-take zones (NTZs) is critical, not just for the effective management of marine resources, but also for informing and gaining support from community stakeholders. The Galapagos Marine Reserve (GMR) established a network of coastal NTZs in 2001, yet, to date no study has investigated their effectiveness in protecting and enabling key species to recover. Using data from the Galapagos National Park Directorate annual Lobster Population Monitoring Program from 2012 to 2014, this study evaluated the recovery of the commercially valuable red spiny lobster ( Panulirus penicillatus ) inside NTZs in the GMR. It was hypothesized that NTZs would present higher lobster abundances or sizes when compared with adjacent fished zones. However, the study found no significant differences in these comparisons. Overall the findings indicate that > 11 years of protection has had no appreciable effect on lobster abundances or sizes inside the NTZs. This paper explores possible reasons for the lack of response in NTZs, and concluded that non-compliance and shortcomings within the enforcement framework of the GMR are the key factors limiting the functionality of these NTZs. Additionally, it also evaluates the limitations of the current monitoring program and highlights the need for a more comprehensive and long-term program to be implemented. As the new zoning scheme for NTZs in the GMR that began in 2016 is still to be determined, this information should be considered by decision makers to improve the effectiveness of NTZs and sustainable management of the GRM's coastal resources. [ABSTRACT FROM AUTHOR]

Abstract: Anthropogenic threats to the global marine environment are increasing, and the Convention of Biological Diversity has set a target of 10% global ocean protection by 2020. Social factors are an important component of coastal marine protected area and no-take marine reserve creation. In order to understand social factors influencing marine reserve creation in New Zealand, public surveys were conducted in 2005 and 2011 about marine protection and threats to the marine environment (Territorial Sea and Exclusive Economic Zone). These results are compared to an experts' opinion survey of threats to the New Zealand marine environment, and actual marine protection levels. Generally, the New Zealand public identified similar New Zealand originated threats to the marine environment as those identified by experts, in contrast to expert identified global threats originating from climate change, which were minimally identified by the public. Experts identified that shallow, coastal waters were under greater threat than deep water habitats. On average, the New Zealand public thought that ~30% of New Zealand’s marine environment was protected by no-take marine reserves, and that 36% should be protected, while in fact only 0.3% is protected by no-take marine reserves. There is considerable potential for publicly driven marine protection initiatives in New Zealand with sufficient awareness, education, and outreach programs to better inform New Zealanders about actual marine protection levels. The results of this study are globally important, as similar knowledge gaps about marine environmental issues have been identified in the United States and the United Kingdom. [Copyright &y& Elsevier]

Highlights: [•] We have developed a present day ecosystem model for the Taputeranga MR. [•] We have historically reconstructed the ecosystem state prior to commercial fishing. [•] We have run future simulations to predict ecosystem response to marine protection. [•] The keystone role of lobster has changed since historical times due to fishing. [•] The Taputeranga MR is predicted to return the ecosystem to a more historical state. [Copyright &y& Elsevier]

• Experimental study identifying uncertainty sources in FishMIP global model ensemble. • Warming and lower trophic level (LTL) impacts on model predictions isolated. • Coupling of lower and higher trophic levels a key driver of model warming response. • LTL impacts driven primarily by each model's choice of LTL driver. • Overall climate projections mostly a linear combination of warming and LTL impacts. Climate change is warming the ocean and impacting lower trophic level (LTL) organisms. Marine ecosystem models can provide estimates of how these changes will propagate to larger animals and impact societal services such as fisheries, but at present these estimates vary widely. A better understanding of what drives this inter-model variation will improve our ability to project fisheries and other ecosystem services into the future, while also helping to identify uncertainties in process understanding. Here, we explore the mechanisms that underlie the diversity of responses to changes in temperature and LTLs in eight global marine ecosystem models from the Fisheries and Marine Ecosystem Model Intercomparison Project (FishMIP). Temperature and LTL impacts on total consumer biomass and ecosystem structure (defined as the relative change of small and large organism biomass) were isolated using a comparative experimental protocol. Total model biomass varied between −35% to +3% in response to warming, and -17% to +15% in response to LTL changes. There was little consensus about the spatial redistribution of biomass or changes in the balance between small and large organisms (ecosystem structure) in response to warming, an LTL impacts on total consumer biomass varied depending on the choice of LTL forcing terms. Overall, climate change impacts on consumer biomass and ecosystem structure are well approximated by the sum of temperature and LTL impacts, indicating an absence of nonlinear interaction between the models' drivers. Our results highlight a lack of theoretical clarity about how to represent fundamental ecological mechanisms, most importantly how temperature impacts scale from individual to ecosystem level, and the need to better understand the two-way coupling between LTL organisms and consumers. We finish by identifying future research needs to strengthen global marine ecosystem modelling and improve projections of climate change impacts. [ABSTRACT FROM AUTHOR]