Hidden impacts of ocean warming and acidification on biological responses of marine animals revealed through meta-analysis.

Conflicting results remain on the impacts of climate change on marine organisms, hindering our capacity to predict the future state of marine ecosystems. To account for species-specific responses and for the ambiguous relation of most metrics to fitness, we develop a meta-analytical approach based on the deviation of responses from reference values (absolute change) to complement meta-analyses of directional (relative) changes in responses. Using this approach, we evaluate responses of fish and invertebrates to warming and acidification. We find that climate drivers induce directional changes in calcification, survival, and metabolism, and significant deviations in twice as many biological responses, including physiology, reproduction, behavior, and development. Widespread deviations of responses are detected even under moderate intensity levels of warming and acidification, while directional changes are mostly limited to more severe intensity levels. Because such deviations may result in ecological shifts impacting ecosystem structures and processes, our results suggest that climate change will likely have stronger impacts than those previously predicted based on directional changes alone.

Deficiencies in monitoring practices of marine protected areas in southern European seas.

Worldwide, states are gazetting new Marine Protected Areas (MPAs) to meet the international commitment of protecting 30% of the seas by 2030. Yet, protection benefits only come into effect when an MPA is implemented with activated regulations and actively managed through continuous monitoring and adaptive management. To assess if actively managed MPAs are the rule or the exception, we used the Mediterranean and Black Seas as a case study, and retrieved information on monitoring activities for 878 designated MPAs in ten European Union (EU) countries. We searched for scientific and grey literature that provides information on the following aspects of MPA assessment and monitoring: ecological (e.g., biomass of commercially exploited fish), social (e.g., perceptions of fishers in an MPA), economic (e.g., revenue of fishers) and governance (e.g., type of governance scheme). We also queried MPA authorities on their past and current monitoring activities using a web-based survey through which we collected 123 responses. Combining the literature review and survey results, we found that approximately 16% of the MPA designations (N = 878) have baseline and/or monitoring studies. Most monitoring programs evaluated MPAs based solely on biological/ecological variables and fewer included social, economic and/or governance variables, failing to capture and assess the social-ecological dimension of marine conservation. To increase the capacity of MPAs to design and implement effective social-ecological monitoring programs, we recommend strategies revolving around three pillars: funding, collaboration, and technology. Following the actionable recommendations presented herein, MPA authorities and EU Member States could improve the low level of MPA monitoring to more effectively reach the 30% protection target delivering benefits for biodiversity conservation.

Effects of management objectives and rules on marine conservation outcomes.

Understanding the relative effectiveness and enabling conditions of different area-based management tools is essential for supporting efforts that achieve positive biodiversity outcomes as area-based conservation coverage increases to meet newly set international targets. We used data from a coastal social-ecological monitoring program in 6 Indo-Pacific countries to analyze whether social, ecological, and economic objectives and specific management rules (temporal closures, fishing gear-specific, species-specific restrictions) were associated with coral reef fish biomass above sustainable yield levels across different types of area-based management tools (i.e., comparing those designated as marine protected areas [MPAs] with other types of area-based management). All categories of objectives, multiple combinations of rules, and all types of area-based management had some sites that were able to sustain high levels of reef fish biomass-a key measure for coral reef functioning-compared with reference sites with no area-based management. Yet, the same management types also had sites with low biomass. As governments advance their commitments to the Kunming-Montreal Global Biodiversity Framework and the target to conserve 30% of the planet's land and oceans by 2030, we found that although different types of management can be effective, most of the managed areas in our study regions did not meet criteria for effectiveness. These findings underscore the importance of strong management and governance of managed areas and the need to measure the ecological impact of area-based management rather than counting areas because of their designation.

Efectos de las reglas y objetivos de manejo sobre los resultados de conservación marina Resumen Es esencial entender la efectividad relativa y las condiciones habilitantes de las diferentes herramientas de manejo basadas en el área para respaldar los esfuerzos que brindan resultados positivos para la biodiversidad conforme aumenta la cobertura de la conservación basada en el área para alcanzar los objetivos internacionales recién establecidos. Usamos los datos de un programa de monitoreo socioeconómico costero en seis países del Indo-Pacífico para analizar si los objetivos sociales, ecológicos y económicos y las reglas específicas de manejo (cierres temporales, restricciones de equipo de pesca, vedas de especies) se asociaban con la biomasa de los peces de arrecife de coral por encima de los niveles de producción sustentable en diferentes tipos de herramientas de manejo basadas en el área (es decir, comparar aquellas designadas como áreas marinas protegidas[AMP] con otros tipos de manejo basado en el área). Todas las categorías de objetivos, las múltiples combinaciones de reglas y todos los tipos de manejo basado en el área tuvieron algunos sitios capaces de mantener los niveles altos de biomasa de peces de arrecife-una medida importante para el funcionamiento de los arrecifes-en comparación con los sitios de referencia sin manejo basado en el área. Sin embargo, los mismos tipos de manejo también tuvieron sitios con baja biomasa. Conforme los gobiernos avanzan en sus compromisos con el Marco Global de Biodiversidad de Kunming-Montreal y hacia el objetivo de conservar el 30% del suelo y los océanos del planeta para el 2030, descubrimos que, aunque diferentes tipos de manejo pueden ser efectivos, la mayoría de las áreas manejadas en nuestras regiones de estudio no cumplieron con los criterios de efectividad. Este descubrimiento enfatiza la importancia de una gestión y un gobierno sólidos de las áreas manejadas y la necesidad de medir el impacto ecológico del manejo basado en el área en lugar de contar las áreas por su designación.

A marine protected area network does not confer community structure resilience to a marine heatwave across coastal ecosystems.

Marine protected areas (MPAs) have gained attention as a conservation tool for enhancing ecosystem resilience to climate change. However, empirical evidence explicitly linking MPAs to enhanced ecological resilience is limited and mixed. To better understand whether MPAs can buffer climate impacts, we tested the resistance and recovery of marine communities to the 2014-2016 Northeast Pacific heatwave in the largest scientifically designed MPA network in the world off the coast of California, United States. The network consists of 124 MPAs (48 no-take state marine reserves, and 76 partial-take or special regulation conservation areas) implemented at different times, with full implementation completed in 2012. We compared fish, benthic invertebrate, and macroalgal community structure inside and outside of 13 no-take MPAs across rocky intertidal, kelp forest, shallow reef, and deep reef nearshore habitats in California's Central Coast region from 2007 to 2020. We also explored whether MPA features, including age, size, depth, proportion rock, historic fishing pressure, habitat diversity and richness, connectivity, and fish biomass response ratios (proxy for ecological performance), conferred climate resilience for kelp forest and rocky intertidal habitats spanning 28 MPAs across the full network. Ecological communities dramatically shifted due to the marine heatwave across all four nearshore habitats, and MPAs did not facilitate habitat-wide resistance or recovery. Only in protected rocky intertidal habitats did community structure significantly resist marine heatwave impacts. Community shifts were associated with a pronounced decline in the relative proportion of cold water species and an increase in warm water species. MPA features did not explain resistance or recovery to the marine heatwave. Collectively, our findings suggest that MPAs have limited ability to mitigate the impacts of marine heatwaves on community structure. Given that mechanisms of resilience to climate perturbations are complex, there is a clear need to expand assessments of ecosystem-wide consequences resulting from acute climate-driven perturbations, and the potential role of regulatory protection in mitigating community structure changes.

Making protected areas effective for biodiversity, climate and food.

The spatial extent of marine and terrestrial protected areas (PAs) was among the most intensely debated issues prior to the decision about the post-2020 Global Biodiversity Framework (GBF) of the Convention on Biological Diversity. Positive impacts of PAs on habitats, species diversity and abundance are well documented. Yet, biodiversity loss continues unabated despite efforts to protect 17% of land and 10% of the oceans by 2020. This casts doubt on whether extending PAs to 30%, the agreed target in the Kunming-Montreal GBF, will indeed achieve meaningful biodiversity benefits. Critically, the focus on area coverage obscures the importance of PA effectiveness and overlooks concerns about the impact of PAs on other sustainability objectives. We propose a simple means of assessing and visualising the complex relationships between PA area coverage and effectiveness and their effects on biodiversity conservation, nature-based climate mitigation and food production. Our analysis illustrates how achieving a 30% PA global target could be beneficial for biodiversity and climate. It also highlights important caveats: (i) achieving lofty area coverage objectives alone will be of little benefit without concomitant improvements in effectiveness, (ii) trade-offs with food production particularly for high levels of coverage and effectiveness are likely and (iii) important differences in terrestrial and marine systems need to be recognized when setting and implementing PA targets. The CBD's call for a significant increase in PA will need to be accompanied by clear PA effectiveness goals to reduce and revert dangerous anthropogenic impacts on socio-ecological systems and biodiversity.

Tracking changes in social-ecological systems along environmental disturbances with the ocean health index.

The well-being of coastal communities is intimately tied to a healthy ocean, but coastal social-ecological systems are among the most vulnerable to global change. Improving the resilience of coastal communities requires an understanding of how local social-ecological systems respond to shocks to better inform decision-making and adapt local management interventions. However, assessments of social-ecological changes throughout a disturbance regime are scarce at the local level, although critical for efficient natural resource management and sustainable use of ocean ecosystem services. Here, we apply the Ocean Health Index (OHI) to assess the status of the marine social-ecological system of a tropical island (Moorea, French Polynesia), and track changes of the system before, during and after a disturbance regime. Our results show that while there are signs of social-ecological recovery, coastal protection was most affected along the disturbance, and that there is room for improvement toward biodiversity conservation. In addition, our study highlights some context-specific challenges associated with local OHI assessments, particularly those driven by limited fisheries data and appropriate reference point selection for coastal protection. Our results demonstrate the value of localized, regular OHI assessments through time to track changes in marine social-ecological systems, while uncovering important data gaps, to inform management at appropriate scales for decision-making.

A forgotten element of the blue economy: marine biomimetics and inspiration from the deep sea.

The morphology, physiology, and behavior of marine organisms have been a valuable source of inspiration for solving conceptual and design problems. Here, we introduce this rich and rapidly expanding field of marine biomimetics, and identify it as a poorly articulated and often overlooked element of the ocean economy associated with substantial monetary benefits. We showcase innovations across seven broad categories of marine biomimetic design (adhesion, antifouling, armor, buoyancy, movement, sensory, stealth), and use this framing as context for a closer consideration of the increasingly frequent focus on deep-sea life as an inspiration for biomimetic design. We contend that marine biomimetics is not only a "forgotten" sector of the ocean economy, but has the potential to drive appreciation of nonmonetary values, conservation, and stewardship, making it well-aligned with notions of a sustainable blue economy. We note, however, that the highest ambitions for a blue economy are that it not only drives sustainability, but also greater equity and inclusivity, and conclude by articulating challenges and considerations for bringing marine biomimetics onto this trajectory.

Mediterranean rocky reefs in the Anthropocene: Present status and future concerns.

Global change is striking harder and faster in the Mediterranean Sea than elsewhere, where high levels of human pressure and proneness to climate change interact in modifying the structure and disrupting regulative mechanisms of marine ecosystems. Rocky reefs are particularly exposed to such environmental changes with ongoing trends of degradation being impressive. Due to the variety of habitat types and associated marine biodiversity, rocky reefs are critical for the functioning of marine ecosystems, and their decline could profoundly affect the provision of essential goods and services which human populations in coastal areas rely upon. Here, we provide an up-to-date overview of the status of rocky reefs, trends in human-driven changes undermining their integrity, and current and upcoming management and conservation strategies, attempting a projection on what could be the future of this essential component of Mediterranean marine ecosystems.

The MPA Guide: A framework to achieve global goals for the ocean.

Marine Protected Areas (MPAs) are conservation tools intended to protect biodiversity, promote healthy and resilient marine ecosystems, and provide societal benefits. Despite codification of MPAs in international agreements, MPA effectiveness is currently undermined by confusion about the many MPA types and consequent wildly differing outcomes. We present a clarifying science-driven framework­The MPA Guide­to aid design and evaluation. The guide categorizes MPAs by stage of establishment and level of protection, specifies the resulting direct and indirect outcomes for biodiversity and human well-being, and describes the key conditions necessary for positive outcomes. Use of this MPA Guide by scientists, managers, policy-makers, and communities can improve effective design, implementation, assessment, and tracking of existing and future MPAs to achieve conservation goals by using scientifically grounded practices.

Cumulative impact assessments highlight the benefits of integrating land-based management with marine spatial planning.

Cumulative impact assessments can inform ecosystem-based management by mapping human pressures and assessing their intensity on ecosystem components. However, its use to inform local management is scarce, largely due to the need for fine-grained spatial data representing ecosystem threats that can assess impacts at a local scale. Here, we applied the cumulative impact assessment framework to Moorea's coral reef, French Polynesia to inform the ongoing revision of the island-wide marine spatial management plan. We combined high spatial resolution data on 11 local anthropogenic pressures and four ecological components with expert vulnerability assessments. Results revealed that the entire reef is impacted by at least four pressures: coral reef fisheries, agriculture, land use change and urbanization. These activities together contribute to 87% of the overall cumulative impact. Most importantly, land-based activities contribute to more than half (52%) of the overall impact. Other high-impact activities, such as reef-based tourism, remain very localized and contribute little to the overall human impact. These findings show that by focusing solely on reef-based activities, the current management plan misses critical sources of impact. Not considering land-based activities in the management may lead to decisions that could fail to significantly lower cumulative human impact on the reef. This study demonstrates how operationalizing the cumulative human impact framework at a local scale can help managers identify key leverage points likely to yield improved ecological outcomes.

Increased connectivity and depth improve the effectiveness of marine reserves.

Marine reserves are a key tool for the conservation of marine biodiversity, yet only ~2.5% of the world's oceans are protected. The integration of marine reserves into connected networks representing all habitats has been encouraged by international agreements, yet the benefits of this design has not been tested empirically. Australia has one of the largest systems of marine reserves, providing a rare opportunity to assess how connectivity influences conservation success. An Australia-wide dataset was collected using baited remote underwater video systems deployed across a depth range from 0 to 100 m to assess the effectiveness of marine reserves for protecting teleosts subject to commercial and recreational fishing. A meta-analytical comparison of 73 fished species within 91 marine reserves found that, on average, marine reserves had 28% greater abundance and 53% greater biomass of fished species compared to adjacent areas open to fishing. However, benefits of protection were not observed across all reserves (heterogeneity), so full subsets generalized additive modelling was used to consider factors that influence marine reserve effectiveness, including distance-based and ecological metrics of connectivity among reserves. Our results suggest that increased connectivity and depth improve the aforementioned marine reserve benefits and that these factors should be considered to optimize such benefits over time. We provide important guidance on factors to consider when implementing marine reserves for the purpose of increasing the abundance and size of fished species, given the expected increase in coverage globally. We show that marine reserves that are highly protected (no-take) and designed to optimize connectivity, size and depth range can provide an effective conservation strategy for fished species in temperate and tropical waters within an overarching marine biodiversity conservation framework.

The seven domains of action for a sustainable ocean.

The ocean strongly contributes to our well-being but is severely impacted by human activities. Here, I propose seven domains of action to structure our collective efforts toward a scientifically sound, just, and holistic governance of a sustainable ocean.

Landscape-scale patterns of nutrient enrichment in a coral reef ecosystem: implications for coral to algae phase shifts.

Nutrient pollution is altering coastal ecosystems worldwide. On coral reefs, excess nutrients can favor the production of algae at the expense of reef-building corals, yet the role of nutrients in driving community changes such as shifts from coral to macroalgae is not well understood. Here we investigate the potential role of anthropogenic nutrient loading in driving recent coral-to-macroalgae phase shifts on reefs in the lagoons surrounding the Pacific island of Moorea, French Polynesia. We use nitrogen (N) tissue content and stable isotopes (δ15 N) in an abundant macroalga (Turbinaria ornata) together with empirical models of nutrient discharge to describe spatial and temporal patterns of nutrient enrichment in the lagoons. We then employ time series data to test whether recent increases in macroalgae are associated with nutrients. Our results revealed that patterns of N enrichment were linked to several factors, including rainfall, wave-driven circulation, and distance from anthropogenic nutrient sources, especially human sewage. Reefs near large watersheds, where inputs of N from sewage and agriculture are high, have been consistently enriched in N for at least the last decade. In many of these areas, corals have decreased and macroalgae have increased, while reefs with lower levels of N input have maintained high cover of coral and low cover of macroalgae. Importantly, these patchy phase shifts to macroalgae have occurred despite substantial island-wide increases in the density and biomass of herbivorous fishes over the time period. Together, these results indicate that nutrient loading may be an important driver of coral-to-macroalgae phase shifts in the lagoons of Moorea even though the reefs harbor an abundant and diverse herbivore assemblage. These results emphasize the important role that bottom-up factors can play in driving coral-to-macroalgae phase shifts and underscore the critical importance of watershed management for reducing inputs of nutrients and other land-based pollutants to coral reef ecosystems.

Convergence of stakeholders' environmental threat perceptions following mass coral bleaching of the Great Barrier Reef.

Managing human use of ecosystems in an era of rapid environmental change requires an understanding of diverse stakeholders' behaviors and perceptions to enable effective prioritization of actions to mitigate multiple threats. Specifically, research examining how threat perceptions are shared or diverge among stakeholder groups and how these can evolve through time is increasingly important. We investigated environmental threat perceptions related to Australia's Great Barrier Reef and explored their associations before and after consecutive years of mass coral bleaching. We used data from surveys of commercial fishers, tourism operators, and coastal residents (n = 5254) conducted in 2013 and 2017. Threats perceived as most serious differed substantially among groups before bleaching but were strongly aligned after bleaching. Climate change became the most frequently reported threat by all stakeholder groups following the coral bleaching events, and perceptions of fishing and poor water quality as threats also ranked high. Within each of the 3 stakeholder groups, fishers, tourism operators, and coastal residents, the prioritization of these 3 threats tended to diverge in 2013, but convergence occurred after bleaching. These results indicate an emergence of areas of agreement both within and across stakeholder groups. Changes in perceptions were likely influenced by high-profile environmental-disturbance events and media representations of threats. Our results provide insights into the plasticity of environmental-threat perceptions and highlight how their convergence in response to major events may create new opportunities for strategic public engagement and increasing support for management.

Convergencia de la Percepción de las Amenazas Ambientales por los Actores Sociales después del Blanqueamiento Masivo del Coral de la Gran Barrera Arrecifal Resumen La administración del uso que las personas dan a los ecosistemas en una época de cambios ambientales rápidos requiere un entendimiento del comportamiento de diferentes actores sociales y sus percepciones para facilitar la priorización de las acciones que mitigan a las múltiples amenazas. Específicamente, las investigaciones que examinan cómo se comparten o difieren las percepciones de las amenazas entre los grupos de actores y cómo estas percepciones pueden evolucionar con el tiempo son cada vez más importantes. Investigamos las percepciones de las amenazas ambientales relacionadas con la Gran Barrera Arrecifal en Australia y exploramos sus asociaciones antes y después de varios años consecutivos de blanqueamiento masivo del coral. Usamos datos tomados de encuestas realizadas a pescadores comerciales, operadores turísticos y residentes de la costa (n = 5,254) en 2013 y 2017. Las amenazas percibidas como las más serias difirieron sustancialmente entre los tres grupos antes del blanqueamiento, pero se alinearon marcadamente después del blanqueamiento. El cambio climático se convirtió en la amenaza reportada con mayor frecuencia por todos los grupos de actores después de los eventos de blanqueamiento del coral. Las percepciones de la pesca y la baja calidad del agua como amenazas también tuvieron una clasificación alta. Dentro de cada uno de los tres grupos de actores (pescadores, operadores turísticos y residentes de la costa) la priorización de estas tres amenazas tendió a diferir en 2013 pero la convergencia ocurrió después del blanqueamiento. Estos resultados indican un surgimiento de áreas de acuerdo dentro y entre los grupos de actores. Los cambios en las percepciones probablemente estuvieron influenciados por eventos de perturbación ambiental de alto perfil y la representación mediática de las amenazas. Nuestros resultados proporcionaron conocimiento sobre la plasticidad de las percepciones de las amenazas ambientales y resalta cómo su convergencia en la respuesta a los eventos más importantes puede crear nuevas oportunidades para la participación estratégica del público e incrementar el apoyo para su manejo.

Quantifying and addressing the prevalence and bias of study designs in the environmental and social sciences.

Building trust in science and evidence-based decision-making depends heavily on the credibility of studies and their findings. Researchers employ many different study designs that vary in their risk of bias to evaluate the true effect of interventions or impacts. Here, we empirically quantify, on a large scale, the prevalence of different study designs and the magnitude of bias in their estimates. Randomised designs and controlled observational designs with pre-intervention sampling were used by just 23% of intervention studies in biodiversity conservation, and 36% of intervention studies in social science. We demonstrate, through pairwise within-study comparisons across 49 environmental datasets, that these types of designs usually give less biased estimates than simpler observational designs. We propose a model-based approach to combine study estimates that may suffer from different levels of study design bias, discuss the implications for evidence synthesis, and how to facilitate the use of more credible study designs.

Beauty and the reef: Evaluating the use of non-expert ratings for monitoring aesthetic values of coral reefs.

Aesthetic values are a key driver of tourist and recreational visitation to natural areas and are listed among the selection criteria for World Heritage properties. However, assessment and monitoring of aesthetic values in natural areas, and coral reefs in particular, have proven to be challenging. In our study we explored the value and limitations of a rapid assessment approach involving non-expert ratings of aesthetic beauty as a potential tool for long-term monitoring of aesthetic values in the Great Barrier Reef World Heritage Area, Australia. We investigated the sensitivity of a rating scale for detecting change and sampling requirements for monitoring, as well as observer biases, using an online survey of 1417 Australians in which respondents rated the aesthetic beauty of 181 coral reef images on a ten-point scale. Our results show average aesthetic rating scores ranged from 4.35 to 8.34 on a scale from 1 (ugly) to 10 (beautiful), with potential to detect differences of statistical significance within one point, indicating sufficient sensitivity to change for monitoring purposes. We found that a sample size of c.100 ratings per image provided a reasonable balance between cost (i.e. sample size) and accuracy (i.e. error). Older respondents (>65 years) with higher levels of coral reef visitation, experience and interest were more likely to give extreme ratings, however, there was no apparent predictor for this bias to be positive or negative (high or low ratings). Based on these results we provide recommendations to assist coral reef managers in their use and interpretation of non-expert aesthetic ratings in coral reef monitoring.