Evaluating the social and ecological effectiveness of partially protected marine areas

A Bayesian framework linking perceived social-ecological effectiveness to stakeholder acceptance in China's Sousa chinensis protected areas

Enhancing stakeholder acceptance of marine protected areas (MPAs) is key to fulfilling the 30 × 30 Target, ocean-related Sustainable Development Goals, and the UN Decade of Ocean Science for Sustainable Development (2021-2030). These require MPAs not merely as management interventions, but also as social-ecological systems (SESs), where social-ecological effectiveness is the complex coupling of social and ecological effectiveness through interactions. However, the relationships between perceived social-ecological effectiveness and stakeholder acceptance are often indirect and mediated, while traditional models can yield statistical instabilities, risking false conclusions. This article tentatively proposes a partially informative Bayesian posterior framework with three steps and five criteria, using a theoretically based regulator formula and an inverse-Wishart prior in a penalized likelihood function for stricter estimates. Using field surveys and remote sensing data of China's Sousa chinensis MPAs, the study tentatively explores the proposed framework through stakeholder perceptions. Bayesian estimates improved model convergence, positive definiteness and nonsingularity, revealing an average 63 % underestimation of standard errors. Monte Carlo bootstrapping suggested the chain mediation and layered mechanisms, whereby perceived ecological effectiveness is related to stakeholder acceptance through perceived social effectiveness and stakeholder-MPA interaction. Practical implications include socially effective conservation, community-based activities, and stakeholder acceptance monitoring by the scientific community. The framework with more informative Bayesian methods may offer preliminary insights for broader biological conservation settings and practices, subject to contextual adaptations.

Marine protected areas for dive tourism

Marine and coastal tourism deliver economic benefits to coastal communities that far surpass those generated by fisheries, yet its potential contribution to global marine conservation remains underexamined. Marine Protected Areas (MPAs) help restore biodiversity and enhance nearby fisheries, but their direct tourism benefits are not well understood. Here, we estimate the global demand for recreational scuba dive tourism, map the distribution and protection status of all marine dive sites globally, and develop a bioeconomic model to estimate the revenue gains from upgrading unprotected dive sites to fully protected MPAs. We estimate that 33.1 million scuba dives occur annually in marine environments worldwide, with 70% taking place within MPAs. However, only 15% of these MPA-affiliated dive sites are highly or fully protected. We show that designating all unprotected recreational dive sites, representing less than 1% of the global ocean, as highly or fully protected MPAs would improve fish biomass and biodiversity while generating an additional US$2 billion per year in direct tourism revenue (not including economic multipliers). Importantly, 62% of marine diving currently occurs in developing countries, underscoring the potential for dive tourism to support both marine conservation and local livelihoods in regions where such benefits are most needed.

The ambiguous role of partially protected marine protected areas in Australia: Results from a systematic literature review

Marine protected areas (MPAs) are an important tool in helping to protect biodiversity in the oceans. Recent ratification of the Kunming-Montreal Global Biodiversity Framework (GBF) has ensured that globally we are committed to effectively protecting 30% of the world's oceans by 2030, in MPAs. In Australia there is considerable interest in the potential benefits that partially protected areas (PPAs) may provide. However, a consistent definition of a PPA is currently lacking, and urgently needed to conduct quantitative analyses of PPAs. We conducted a systematic literature review to understand the current knowledge surrounding PPAs and their potential benefits. We define a PPA, characterise PPA implementation in Australia, and present results for the outcomes of PPAs in terms of ecological, economic, and social indicators. Our review suggests that although 45% of Australia's marine environment is within MPAs, 61% of MPAs provide only partial protection. The Northern Territory (100%), New South Wales (81%), and Queensland (79.8%) have the highest percentage of MPAs that are partially protected, compared to Tasmania which has the smallest percentage of partially protected MPAs (13.12%). Tasmania also has the smallest percentage cover of MPAs (6.49% state waters). Most PPA management plans did not contain quantifiable Key Performance Indicators (KPIs) to be able to effectively monitor the progress of these PPAs against the stated outcomes. We find the benefits of PPAs to be ambiguous: PPAs generally provide benefits when compared to 'open' ocean, however this is not a consistent result. There are no PPAs that provide greater overall benefits when compared to fully protected MPAs. Only one state (South Australia) and the Commonwealth (Australian Marine Parks) are collecting publicly available baseline data to facilitate quantitative monitoring of PPAs. Contrary to fisheries management, there were no plans of action if the declared MPAs and PPAs failed to meet their declared objectives and goals. Some PPAs within Australia appear to be incompatible with conservation priorities according to the recent "MPA Guide" classification framework. This study highlights the need for clearer management rationale and plans for PPAs in Australia, as these comprise the majority of MPAs in Australia's Exclusive Economic Zone.

The socioeconomic and environmental niche of protected areas reveals global conservation gaps and opportunities

The global network of protected areas has rapidly expanded in the past decade and is expected to cover at least 30% of land and sea by 2030 to halt biodiversity erosion. Yet, the distribution of protected areas is highly heterogeneous on Earth and the social-environmental preconditions enabling or hindering protected area establishment remain poorly understood. Here, using fourteen socioeconomic and environmental factors, we characterize the multidimensional niche of terrestrial and marine protected areas, which we use to accurately establish, at the global scale, whether a particular location has preconditions favourable for paestablishment. We reveal that protected areas, particularly the most restrictive ones, over-aggregate where human development and the number of non-governmental organizations are high. Based on the spatial distribution of vertebrates and the likelihood to convert non-protected areas into strictly protected areas, we identify 'potential' versus 'unrealistic' conservation gains on land and sea, which we define as areas of high vertebrate diversity that are, respectively, favourable and unfavourable to protected area establishment. Where protected areas are unrealistic, alternative strategies such as other effective area-based conservation measures or privately protected areas, could deliver conservation outcomes.

Protection efforts have resulted in ~10% of existing fish biomass on coral reefs

The amount of ocean protected from fishing and other human impacts has often been used as a metric of conservation progress. However, protection efforts have highly variable outcomes that depend on local conditions, which makes it difficult to quantify what coral reef protection efforts to date have actually achieved at a global scale. Here, we develop a predictive model of how local conditions influence conservation outcomes on ~2,600 coral reef sites across 44 ecoregions, which we used to quantify how much more fish biomass there is on coral reefs compared to a modeled scenario with no protection. Under the assumptions of our model, our study reveals that without existing protection efforts there would be ~10% less fish biomass on coral reefs. Thus, we estimate that coral reef protection efforts have led to approximately 1 in every 10 kg of existing fish biomass.

Fishery Management Enforcement Gradients to Achieve Fishery Goals

Marine protected areas (MPAs) can allow some fish populations to rebuild within their borders in areas impacted by overfishing, but the effectiveness of reserves is highly dependent on how effectively fishing mortality is controlled, which in turn depends on the level of fishery management implementation. In Cuba’s Gardens of the Queen MPA, the largest in the Caribbean, a variety of fishery management measures have been implemented to ensure the social, economic, and political viability of protecting such a large area. Here, we evaluate the biological response, in terms of fish density and the biomass of commercially valuable and ecologically important reef fish species, to a spatial gradient of fishery management enforcement, in terms of fish density and biomass, of commercially valuable and ecologically important reef fish species. The enforcement gradient is characterized by the level of protection, fishing effort, patrolling effort, distance to the nearest fishing port, and fishing intensity. Fish density and biomass were estimated from visual scuba surveys. Areas with higher levels of enforcement support higher levels of average biomass (up to 1378 kg/ha) and density (up to 2367 indv./ha) of commercially important fishes in comparison to areas with very low or no enforcement (estimates of 757 kg/ha average biomass and 1090 indv./ha average density, respectively). These fish density and biomass levels can serve as proxies in the development of harvest control rules that adjust fishing pressure according to the ratio of fished density or biomass to unfished density or biomass, through the use of the MPA Density Ratio method.

Effectiveness of marine protected areas in safeguarding important migratory megafauna habitat

Marine protected areas (MPAs) are a commonly used management tool to safeguard marine life from anthropogenic impacts, yet their efficacy often remains untested. Evaluating how highly dynamic marine species use static MPAs is challenging but becoming more feasible with the advancement of telemetry data. Here, we focus on southern right whales (Eubalaena australis, SRWs) in the waters off Aotearoa/New Zealand, which declined from 30,000 whales to fewer than 40 mature females due to whaling. Now numbering in the low thousands, the key socializing and nursery areas for this population in the remote subantarctic islands are under the protection of different types of MPAs. However, the effectiveness of these MPAs in encompassing important whale habitat and protecting the whales from vessel traffic has not been investigated. To address this, we analyzed telemetry data from 29 SRWs tagged at the Auckland Islands between 2009 and 2022. We identified two previously unknown and currently unprotected areas that were used by the whales for important behaviors such as foraging, socializing, or resting. Additionally, by combining whale locations and vessel tracking data (2020-2022) during peak breeding period (June to October), we found high spatiotemporal overlap between whales and vessels within several MPAs, suggesting the whales could still be vulnerable to multiple anthropogenic stressors even when within areas designated for protection. Our results identify areas to be prioritized for future monitoring and investigation to support the ongoing recovery of this SRW population, as well as highlight the overarching importance of assessing MPA effectiveness post-implementation, especially in a changing climate.

A pulse check for trends in sea turtle numbers across the globe

Population declines of vertebrates are common, but rebuilding marine life may be possible. We assessed trends in sea turtle numbers globally, building 61 time series of abundance extending beyond 2015, representing monitoring in >1200 years. Increases were widespread with significant upward trends, no significant change, and significant downward trends in 28, 28, and 5 time series, respectively. For example, annual nest numbers increased between 1980 and 2018 from around 4,000 to 16,000 for green turtles at Aldabra (Seychelles, Indian Ocean) and between 2008 and 2020 from around 500 to 35,000 for loggerhead turtles in Sal (Cape Verde, north Atlantic). However, conservation concerns remain. Major populations may experience declines, such as loggerhead turtles in Oman, while previous upward trends can be reversed, as with green turtles nesting at Tortuguero (Costa Rica, Caribbean). Further, decreases in abundance were evident in several leatherback turtle time series. These concerns show there is no room for complacency for sea turtle conservation.

Global status, impacts, and management of rocky temperate mesophotic ecosystems

The ecology and function of rocky temperate mesophotic ecosystems (TMEs) remain poorly understood globally despite their widespread distribution. They typically occur at 20-150 m (the limit of photosynthesis), and on rocky substratum they support rich benthic communities and mobile fauna. We determined the distribution of rocky TMEs, their conservation status, and their most characteristic biological groups. Rocky TMEs were dominated by algae, turf-invertebrate matrices (<50 m only), sponges, bryozoans, and cnidarians. The community composition of TMEs differed significantly from shallow (0-15 m) subtidal reefs. Data were geographically biased and variable, available only from the North and South Atlantic, Mediterranean, and Temperate Australasia. Degree of protection of rocky TMEs varied considerably across the world. The biggest threats to rocky TMEs were identified changes in temperature, sedimentation rates, nutrient concentrations, and certain fishing types. We propose a conservation framework to inform future rocky TME management and conservation, highlighting the need to recognize the importance of these biologically diverse and functionally important ecosystems.

Ecological effectiveness of marine protected areas across the globe in the scientific literature

A systematic literature review (SLR) of scientific articles on the effectiveness of marine protected areas (MPAs) to conserve biodiversity in the 2010-2019 decade using Scopus was done. Only studies that used Before-After-Control-Impact (BACI-type) research designs and at least one marine biodiversity indicator were included. The 23 studies included in the review were published in 19 journals and comprised 66 MPAs from 18 countries from the five continents. Fifty-seven percent of the studies used species-specific indicators of MPA effectiveness, chiefly density/abundance and size of organisms. Over 90% of the studies used incomplete research designs, with just 9% using BACI-type designs or over. Just over half of the studies reported positive or slightly positive ecological outcomes from MPAs, with 17.4% of them reporting negative or slightly negative outcomes, and 30.4% reporting mixed or inconclusive outcomes. Legally stringent reserves clearly outperformed multiple-use MPAs ecologically. The major stated pressures to both types of MPAs related to fishing, whereas the main mentioned MPA effectiveness factors included managerial and regulatory issues. Our results add to the existing evidence that the global ocean coverage by legally stringent reserves should be expanded if effective marine biodiversity conservation is to be achieved.

Glimmers of hope in large carnivore recoveries

In the face of an accelerating extinction crisis, scientists must draw insights from successful conservation interventions to uncover promising strategies for reversing broader declines. Here, we synthesize cases of recovery from a list of 362 species of large carnivores, ecologically important species that function as terminal consumers in many ecological contexts. Large carnivores represent critical conservation targets that have experienced historical declines as a result of direct exploitation and habitat loss. We examine taxonomic and geographic variation in current extinction risk and recovery indices, identify conservation actions associated with positive outcomes, and reveal anthropogenic threats linked to ongoing declines. We find that fewer than 10% of global large carnivore populations are increasing, and only 12 species (3.3%) have experienced genuine improvement in extinction risk, mostly limited to recoveries among marine mammals. Recovery is associated with species legislation enacted at national and international levels, and with management of direct exploitation. Conversely, ongoing declines are robustly linked to threats that include habitat modification and human conflict. Applying lessons from cases of large carnivore recovery will be crucial for restoring intact ecosystems and maintaining the services they provide to humans.

Impact of marine protected areas on temporal stability of fish species diversity

Preserving biodiversity over time is a pressing challenge for conservation science. A key goal of marine protected areas (MPAs) is to maintain stability in species composition, via reduced turnover, to support ecosystem function. Yet, this stability is rarely measured directly under different levels of protection. Rather, evaluations of MPA efficacy generally consist of static measures of abundance, species richness, and biomass, and rare measures of turnover are limited to short-term studies involving pairwise (beta diversity) comparisons. Zeta diversity is a recently developed metric of turnover that allows for measurement of compositional similarity across multiple assemblages and thus provides more comprehensive estimates of turnover. We evaluated the effectiveness of MPAs at preserving fish zeta diversity across a network of marine reserves over 10 years in Batemans Marine Park, Australia. Snorkel transect surveys were conducted across multiple replicated and spatially interspersed sites to record fish species occurrence through time. Protection provided by MPAs conferred greater stability in fish species turnover. Marine protected areas had significantly shallower decline in zeta diversity compared with partially protected and unprotected areas. The retention of harvested species was four to six times greater in MPAs compared with partially protected and unprotected areas, and the stabilizing effects of protection were observable within 4 years of park implementation. Conversely, partial protection offered little to no improvement in stability, compared with unprotected areas. These findings support the efficacy of MPAs for preserving temporal fish diversity stability. The implementation of MPAs helps stabilize fish diversity and may, therefore, support biodiversity resilience under ongoing environmental change.

Employing CRISPR/Cas Technology for the Improvement of Potato and Other Tuber Crops

New breeding technologies have not only revolutionized biological science, but have also been employed to generate transgene-free products. Genome editing is a powerful technology that has been used to modify genomes of several important crops. This review describes the basic mechanisms, advantages and disadvantages of genome editing systems, such as ZFNs, TALENs, and CRISPR/Cas. Secondly, we summarize in detail all studies of the CRISPR/Cas system applied to potato and other tuber crops, such as sweet potato, cassava, yam, and carrot. Genes associated with self-incompatibility, abiotic-biotic resistance, nutrient-antinutrient content, and post-harvest factors targeted utilizing the CRISPR/Cas system are analyzed in this review. We hope that this review provides fundamental information that will be useful for future breeding of tuber crops to develop novel cultivars.

Maximizing regional biodiversity requires a mosaic of protection levels

Protected areas are the flagship management tools to secure biodiversity from anthropogenic impacts. However, the extent to which adjacent areas with distinct protection levels host different species numbers and compositions remains uncertain. Here, using reef fishes, European alpine plants, and North American birds, we show that the composition of species in adjacent Strictly Protected, Restricted, and Non-Protected areas is highly dissimilar, whereas the number of species is similar, after controlling for environmental conditions, sample size, and rarity. We find that between 12% and 15% of species are only recorded in Non-Protected areas, suggesting that a non-negligible part of regional biodiversity occurs where human activities are less regulated. For imperiled species, the proportion only recorded in Strictly Protected areas reaches 58% for fishes, 11% for birds, and 7% for plants, highlighting the fundamental and unique role of protected areas and their environmental conditions in biodiversity conservation.

This study shows that the dissimilarity in species composition between sites with different levels of protection is consistently high, suggesting that adjacent and connected areas with different protection levels host very dissimilar species assemblages.