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1.
Sci Adv ; 10(41): eadn3874, 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39392891

RESUMEN

A central barrier to effective governance and accountability in fisheries is the limited transparency of corporate ownership. Transshipment-the transfer of catches, fuel, parts, or crew between fishing and cargo vessels known as reefers-is often criticized for its opacity and poor governance. Better insight into the beneficial ownership of vessels involved in transshipment and their operational patterns could lead to more effective management. Our study presents a publicly accessible database of reefers' owners, operators, and flags. We identified 569 individual reefers and found that Russian and Chinese owners control 26 and 20% of the global reefer fleet, respectively. Results also show that 65% of all reefer vessels fly the flags of Russia, Panama, or China. This high level of consolidation suggests considerable leverage for enhancing transparency and governance. Our findings highlight the potential for reforming existing transshipment practices through collaboration among owners, flag states, fishery regulators, and scientists.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Explotaciones Pesqueras , Propiedad , Conservación de los Recursos Naturales/métodos , Arrecifes de Coral , Animales , China , Humanos , Federación de Rusia , Navíos
2.
Nature ; 616(7955): 104-112, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36813964

RESUMEN

Blue foods, sourced in aquatic environments, are important for the economies, livelihoods, nutritional security and cultures of people in many nations. They are often nutrient rich1, generate lower emissions and impacts on land and water than many terrestrial meats2, and contribute to the health3, wellbeing and livelihoods of many rural communities4. The Blue Food Assessment recently evaluated nutritional, environmental, economic and justice dimensions of blue foods globally. Here we integrate these findings and translate them into four policy objectives to help realize the contributions that blue foods can make to national food systems around the world: ensuring supplies of critical nutrients, providing healthy alternatives to terrestrial meat, reducing dietary environmental footprints and safeguarding blue food contributions to nutrition, just economies and livelihoods under a changing climate. To account for how context-specific environmental, socio-economic and cultural aspects affect this contribution, we assess the relevance of each policy objective for individual countries, and examine associated co-benefits and trade-offs at national and international scales. We find that in many African and South American nations, facilitating consumption of culturally relevant blue food, especially among nutritionally vulnerable population segments, could address vitamin B12 and omega-3 deficiencies. Meanwhile, in many global North nations, cardiovascular disease rates and large greenhouse gas footprints from ruminant meat intake could be lowered through moderate consumption of seafood with low environmental impact. The analytical framework we provide also identifies countries with high future risk, for whom climate adaptation of blue food systems will be particularly important. Overall the framework helps decision makers to assess the blue food policy objectives most relevant to their geographies, and to compare and contrast the benefits and trade-offs associated with pursuing these objectives.


Asunto(s)
Organismos Acuáticos , Seguridad Alimentaria , Internacionalidad , Alimentos Marinos , Desarrollo Sostenible , Humanos , Dieta/métodos , Dieta/estadística & datos numéricos , Dieta/tendencias , Ambiente , Carne , Estado Nutricional , Internacionalidad/legislación & jurisprudencia , Alimentos Marinos/economía , Alimentos Marinos/estadística & datos numéricos , Alimentos Marinos/provisión & distribución , Desarrollo Sostenible/economía , Desarrollo Sostenible/legislación & jurisprudencia , Desarrollo Sostenible/tendencias , Seguridad Alimentaria/economía , Seguridad Alimentaria/legislación & jurisprudencia , Seguridad Alimentaria/métodos , Cambio Climático , Política de Salud , Política Ambiental , Factores Socioeconómicos , Características Culturales , Ácidos Grasos Omega-3 , Huella de Carbono , Enfermedades Cardiovasculares/epidemiología
3.
Nat Commun ; 13(1): 1612, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35383162

RESUMEN

Labor abuse on fishing vessels and illegal, unreported and unregulated (IUU) fishing violate human rights, jeopardize food security, and deprive governments of revenues. We applied a multi-method approach, combining new empirical data with satellite information on fishing activities and vessel characteristics to map risks of labor abuse and IUU fishing, understand their relationships, and identify major drivers. Port risks were globally pervasive and often coupled, with 57% of assessed ports associated with labor abuse or IUU fishing. For trips ending in assessed ports, 82% were linked to labor abuse or IUU fishing risks. At-sea risk areas were primarily driven by fishing vessel flags linked to poor control of corruption by the flag state, high ownership by countries other than the flag state, and Chinese-flagged vessels. Transshipment risk areas were related to the gear type of fishing vessels engaged in potential transshipment and carrier vessel flags. Measures at port offer promise for mitigating risks, through the Port State Measures Agreement for IUU fishing, and ensuring sufficient vessel time at port to detect and respond to labor abuse. Our results highlight the need for coordinated action across actors to avoid risk displacement and make progress towards eliminating these socially, environmentally and economically unsustainable practices.


Asunto(s)
Conservación de los Recursos Naturales , Explotaciones Pesqueras , Humanos , Caza
4.
Sci Rep ; 12(1): 3802, 2022 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-35246555

RESUMEN

The biosphere crisis requires changes to existing business practices. We ask how corporations can become sustainability leaders, when constrained by multiple barriers to collaboration for biosphere stewardship. We describe how scientists motivated, inspired and engaged with ten of the world's largest seafood companies, in a collaborative process aimed to enable science-based and systemic transformations (2015-2021). CEOs faced multiple industry crises in 2015 that incentivized novel approaches. New scientific insights, an invitation to collaborate, and a bold vision of transformative change towards ocean stewardship, created new opportunities and direction. Co-creation of solutions resulted in new knowledge and trust, a joint agenda for action, new capacities, international recognition, formalization of an organization, increased policy influence, time-bound goals, and convergence of corporate change. Independently funded scientists helped remove barriers to cooperation, provided means for reflection, and guided corporate strategies and actions toward ocean stewardship. By 2021, multiple individuals exercised leadership and the initiative had transitioned from preliminary and uncomfortable conversations, to a dynamic, operational organization, with capacity to perform global leadership in the seafood industry. Mobilizing transformational agency through learning, collaboration, and innovation represents a cultural evolution with potential to redirect and accelerate corporate action, to the benefit of business, people and the planet.


Asunto(s)
Comercio , Conservación de los Recursos Naturales , Humanos , Industrias , Políticas
5.
Nat Food ; 3(10): 851-861, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-37117898

RESUMEN

Injustices are prevalent in food systems, where the accumulation of vast wealth is possible for a few, yet one in ten people remain hungry. Here, for 194 countries we combine aquatic food production, distribution and consumption data with corresponding national policy documents and, drawing on theories of social justice, explore whether barriers to participation explain unequal distributions of benefits. Using Bayesian models, we find economic and political barriers are associated with lower wealth-based benefits; countries produce and consume less when wealth, formal education and voice and accountability are lacking. In contrast, social barriers are associated with lower welfare-based benefits; aquatic foods are less affordable where gender inequality is greater. Our analyses of policy documents reveal a frequent failure to address political and gender-based barriers. However, policies linked to more just food system outcomes centre principles of human rights, specify inclusive decision-making processes and identify and challenge drivers of injustice.

6.
Nat Food ; 2(9): 673-682, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37117477

RESUMEN

Aquatic foods from marine and freshwater systems are critical to the nutrition, health, livelihoods, economies and cultures of billions of people worldwide, but climate-related hazards may compromise their ability to provide these benefits. Here, we estimate national-level aquatic food system climate risk using an integrative food systems approach that connects climate hazards impacting marine and freshwater capture fisheries and aquaculture to their contributions to sustainable food system outcomes. We show that without mitigation, climate hazards pose high risks to nutritional, social, economic and environmental outcomes worldwide-especially for wild-capture fisheries in Africa, South and Southeast Asia, and Small Island Developing States. For countries projected to experience compound climate risks, reducing societal vulnerabilities can lower climate risk by margins similar to meeting Paris Agreement mitigation targets. System-level interventions addressing dimensions such as governance, gender equity and poverty are needed to enhance aquatic and terrestrial food system resilience and provide investments with large co-benefits towards meeting the Sustainable Development Goals.

7.
Nat Ecol Evol ; 4(8): 1011-1019, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32690904

RESUMEN

We are approaching a reckoning point in 2020 for global targets that better articulate the interconnections between biodiversity, ecosystem services and sustainable development. The Convention on Biological Diversity's (CBD's) post-2020 global biodiversity framework and targets will be developed as we enter the last decade to meet the Sustainable Development Goals (SDGs) and targets. Despite recent findings of unprecedented declines in biodiversity and ecosystem services and their negative impacts on SDGs, these declines remain largely unaccounted for in the SDG's upcoming 'decade of action'. We use a social-ecological systems framework to develop four recommendations for targets that capture the interdependencies between biodiversity, ecosystem services and sustainable development. These recommendations, which are primarily aimed at the CBD post-2020 process, include moving from separate social and ecological targets to social-ecological targets that: account for (1) the support system role of biodiversity and (2) ecosystem services in sustainable development. We further propose target advances that (3) capture social-ecological feedbacks reinforcing unsustainable outcomes, and (4) reveal indirect feedbacks hidden by current target systems. By making these social-ecological interdependencies explicit, it is possible to create coherent systems of global targets that account for the complex role of biodiversity and ecosystem services in sustainable development.


Asunto(s)
Ecosistema , Desarrollo Sostenible , Biodiversidad , Conservación de los Recursos Naturales
9.
Nat Commun ; 6: 7615, 2015 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26172980

RESUMEN

Human pressures on the ocean are thought to be increasing globally, yet we know little about their patterns of cumulative change, which pressures are most responsible for change, and which places are experiencing the greatest increases. Managers and policymakers require such information to make strategic decisions and monitor progress towards management objectives. Here we calculate and map recent change over 5 years in cumulative impacts to marine ecosystems globally from fishing, climate change, and ocean- and land-based stressors. Nearly 66% of the ocean and 77% of national jurisdictions show increased human impact, driven mostly by climate change pressures. Five percent of the ocean is heavily impacted with increasing pressures, requiring management attention. Ten percent has very low impact with decreasing pressures. Our results provide large-scale guidance about where to prioritize management efforts and affirm the importance of addressing climate change to maintain and improve the condition of marine ecosystems.


Asunto(s)
Cambio Climático , Ecosistema , Océanos y Mares , Contaminación del Agua , Monitoreo del Ambiente , Contaminación Ambiental , Explotaciones Pesqueras , Humanos , Análisis Espacio-Temporal
10.
PLoS One ; 10(3): e0117863, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25774678

RESUMEN

International and regional policies aimed at managing ocean ecosystem health need quantitative and comprehensive indices to synthesize information from a variety of sources, consistently measure progress, and communicate with key constituencies and the public. Here we present the second annual global assessment of the Ocean Health Index, reporting current scores and annual changes since 2012, recalculated using updated methods and data based on the best available science, for 221 coastal countries and territories. The Index measures performance of ten societal goals for healthy oceans on a quantitative scale of increasing health from 0 to 100, and combines these scores into a single Index score, for each country and globally. The global Index score improved one point (from 67 to 68), while many country-level Index and goal scores had larger changes. Per-country Index scores ranged from 41-95 and, on average, improved by 0.06 points (range -8 to +12). Globally, average scores increased for individual goals by as much as 6.5 points (coastal economies) and decreased by as much as 1.2 points (natural products). Annual updates of the Index, even when not all input data have been updated, provide valuable information to scientists, policy makers, and resource managers because patterns and trends can emerge from the data that have been updated. Changes of even a few points indicate potential successes (when scores increase) that merit recognition, or concerns (when scores decrease) that may require mitigative action, with changes of more than 10-20 points representing large shifts that deserve greater attention. Goal scores showed remarkably little covariance across regions, indicating low redundancy in the Index, such that each goal delivers information about a different facet of ocean health. Together these scores provide a snapshot of global ocean health and suggest where countries have made progress and where a need for further improvement exists.


Asunto(s)
Fenómenos Ecológicos y Ambientales , Ecosistema , Océanos y Mares , Conservación de los Recursos Naturales , Explotaciones Pesqueras , Internacionalidad
11.
PeerJ ; 2: e308, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24711964

RESUMEN

More diverse communities are thought to be more stable-the diversity-stability hypothesis-due to increased resistance to and recovery from disturbances. For example, high diversity can make the presence of resilient or fast growing species and key facilitations among species more likely. How natural, geographic biodiversity patterns and changes in biodiversity due to human activities mediate community-level disturbance dynamics is largely unknown, especially in diverse systems. For example, few studies have explored the role of diversity in tropical marine communities, especially at large scales. We tested the diversity-stability hypothesis by asking whether coral richness is related to resistance to and recovery from disturbances including storms, predator outbreaks, and coral bleaching on tropical coral reefs. We synthesized the results of 41 field studies conducted on 82 reefs, documenting changes in coral cover due to disturbance, across a global gradient of coral richness. Our results indicate that coral reefs in more species-rich regions were marginally less resistant to disturbance and did not recover more quickly. Coral community resistance was also highly dependent on pre-disturbance coral cover, probably due in part to the sensitivity of fast-growing and often dominant plating acroporid corals to disturbance. Our results suggest that coral communities in biodiverse regions, such as the western Pacific, may not be more resistant and resilient to natural and anthropogenic disturbances. Further analyses controlling for disturbance intensity and other drivers of coral loss and recovery could improve our understanding of the influence of diversity on community stability in coral reef ecosystems.

12.
PLoS One ; 9(1): e82898, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24416151

RESUMEN

In recent decades, many marine populations have experienced major declines in abundance, but we still know little about where management interventions may help protect the highest levels of marine biodiversity. We used modeled spatial distribution data for nearly 12,500 species to quantify global patterns of species richness and two measures of endemism. By combining these data with spatial information on cumulative human impacts, we identified priority areas where marine biodiversity is most and least impacted by human activities, both within Exclusive Economic Zones (EEZs) and Areas Beyond National Jurisdiction (ABNJ). Our analyses highlighted places that are both accepted priorities for marine conservation like the Coral Triangle, as well as less well-known locations in the southwest Indian Ocean, western Pacific Ocean, Arctic and Antarctic Oceans, and within semi-enclosed seas like the Mediterranean and Baltic Seas. Within highly impacted priority areas, climate and fishing were the biggest stressors. Although new priorities may arise as we continue to improve marine species range datasets, results from this work are an essential first step in guiding limited resources to regions where investment could best sustain marine biodiversity.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Internacionalidad , Océanos y Mares , Animales , Clima , Conservación de los Recursos Naturales/economía , Peces/fisiología , Geografía , Actividades Humanas , Humanos , Especificidad de la Especie , Contaminación del Agua
13.
Ecol Evol ; 3(5): 1317-29, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23762518

RESUMEN

Spatially intimate symbioses, such as those between scleractinian corals and unicellular algae belonging to the genus Symbiodinium, can potentially adapt to changes in the environment by altering the taxonomic composition of their endosymbiont communities. We quantified the spatial relationship between the cumulative frequency of thermal stress anomalies (TSAs) and the taxonomic composition of Symbiodinium in the corals Montipora capitata, Porites lobata, and Porites compressa across the Hawaiian archipelago. Specifically, we investigated whether thermally tolerant clade D Symbiodinium was in greater abundance in corals from sites with high frequencies of TSAs. We recovered 2305 Symbiodinium ITS2 sequences from 242 coral colonies in lagoonal reef habitats at Pearl and Hermes Atoll, French Frigate Shoals, and Kaneohe Bay, Oahu in 2007. Sequences were grouped into 26 operational taxonomic units (OTUs) with 12 OTUs associated with Montipora and 21 with Porites. Both coral genera associated with Symbiodinium in clade C, and these co-occurred with clade D in M. capitata and clade G in P. lobata. The latter represents the first report of clade G Symbiodinium in P. lobata. In M. capitata (but not Porites spp.), there was a significant correlation between the presence of Symbiodinium in clade D and a thermal history characterized by high cumulative frequency of TSAs. The endogenous community composition of Symbiodinium and an association with clade D symbionts after long-term thermal disturbance appear strongly dependent on the taxa of the coral host.

14.
PLoS One ; 8(4): e60284, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23593188

RESUMEN

People value the existence of a variety of marine species and habitats, many of which are negatively impacted by human activities. The Convention on Biological Diversity and other international and national policy agreements have set broad goals for reducing the rate of biodiversity loss. However, efforts to conserve biodiversity cannot be effective without comprehensive metrics both to assess progress towards meeting conservation goals and to account for measures that reduce pressures so that positive actions are encouraged. We developed an index based on a global assessment of the condition of marine biodiversity using publically available data to estimate the condition of species and habitats within 151 coastal countries. Our assessment also included data on social and ecological pressures on biodiversity as well as variables that indicate whether good governance is in place to reduce them. Thus, our index is a social as well as ecological measure of the current and likely future status of biodiversity. As part of our analyses, we set explicit reference points or targets that provide benchmarks for success and allow for comparative assessment of current conditions. Overall country-level scores ranged from 43 to 95 on a scale of 1 to 100, but countries that scored high for species did not necessarily score high for habitats. Although most current status scores were relatively high, likely future status scores for biodiversity were much lower in most countries due to negative trends for both species and habitats. We also found a strong positive relationship between the Human Development Index and resilience measures that could promote greater sustainability by reducing pressures. This relationship suggests that many developing countries lack effective governance, further jeopardizing their ability to maintain species and habitats in the future.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/métodos , Conservación de los Recursos Naturales/estadística & datos numéricos , Ecosistema , Biología Marina/métodos , Modelos Lineales , Océanos y Mares , Dinámica Poblacional , Vigilancia de la Población/métodos , Especificidad de la Especie
15.
PLoS One ; 7(8): e42884, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22952618

RESUMEN

Managing coral reefs for resilience to climate change is a popular concept but has been difficult to implement because the empirical scientific evidence has either not been evaluated or is sometimes unsupportive of theory, which leads to uncertainty when considering methods and identifying priority reefs. We asked experts and reviewed the scientific literature for guidance on the multiple physical and biological factors that affect the ability of coral reefs to resist and recover from climate disturbance. Eleven key factors to inform decisions based on scaling scientific evidence and the achievability of quantifying the factors were identified. Factors important to resistance and recovery, which are important components of resilience, were not strongly related, and should be assessed independently. The abundance of resistant (heat-tolerant) coral species and past temperature variability were perceived to provide the greatest resistance to climate change, while coral recruitment rates, and macroalgae abundance were most influential in the recovery process. Based on the 11 key factors, we tested an evidence-based framework for climate change resilience in an Indonesian marine protected area. The results suggest our evidence-weighted framework improved upon existing un-weighted methods in terms of characterizing resilience and distinguishing priority sites. The evaluation supports the concept that, despite high ecological complexity, relatively few strong variables can be important in influencing ecosystem dynamics. This is the first rigorous assessment of factors promoting coral reef resilience based on their perceived importance, empirical evidence, and feasibility of measurement. There were few differences between scientists' perceptions of factor importance and the scientific evidence found in journal publications but more before and after impact studies will be required to fully test the validity of all the factors. The methods here will increase the feasibility and defensibility of including key resilience metrics in evaluations of coral reefs, as well as reduce costs. Adaptation, marine protected areas, priority setting, resistance, recovery.


Asunto(s)
Antozoos/fisiología , Conservación de los Recursos Naturales/métodos , Arrecifes de Coral , Algoritmos , Animales , Clima , Cambio Climático , Ecosistema , Ambiente , Monitoreo del Ambiente , Indonesia , Temperatura
16.
Nature ; 488(7413): 615-20, 2012 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-22895186

RESUMEN

The ocean plays a critical role in supporting human well-being, from providing food, livelihoods and recreational opportunities to regulating the global climate. Sustainable management aimed at maintaining the flow of a broad range of benefits from the ocean requires a comprehensive and quantitative method to measure and monitor the health of coupled human­ocean systems. We created an index comprising ten diverse public goals for a healthy coupled human­ocean system and calculated the index for every coastal country. Globally, the overall index score was 60 out of 100 (range 36­86), with developed countries generally performing better than developing countries, but with notable exceptions. Only 5% of countries scored higher than 70, whereas 32% scored lower than 50. The index provides a powerful tool to raise public awareness, direct resource management, improve policy and prioritize scientific research.


Asunto(s)
Conservación de los Recursos Naturales/estadística & datos numéricos , Ecosistema , Monitoreo del Ambiente/métodos , Internacionalidad , Biología Marina/métodos , Oceanografía/métodos , Agua de Mar , Animales , Política Ambiental , Explotaciones Pesqueras , Geografía , Actividades Humanas/normas , Actividades Humanas/estadística & datos numéricos , Océanos y Mares , Recreación , Contaminación del Agua/análisis
17.
Ecol Appl ; 22(4): 1246-56, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22827132

RESUMEN

Coral reefs are threatened by human activities on both the land (e.g., deforestation) and the sea (e.g., overfishing). Most conservation planning for coral reefs focuses on removing threats in the sea, neglecting management actions on the land. A more integrated approach to coral reef conservation, inclusive of land-sea connections, requires an understanding of how and where terrestrial conservation actions influence reefs. We address this by developing a land-sea planning approach to inform fine-scale spatial management decisions and test it in Fiji. Our aim is to determine where the protection of forest can deliver the greatest return on investment for coral reef ecosystems. To assess the benefits of conservation to coral reefs, we estimate their relative condition as influenced by watershed-based pollution and fishing. We calculate the cost-effectiveness of protecting forest and find that investments deliver rapidly diminishing returns for improvements to relative reef condition. For example, protecting 2% of forest in one area is almost 500 times more beneficial than protecting 2% in another area, making prioritization essential. For the scenarios evaluated, relative coral reef condition could be improved by 8-58% if all remnant forest in Fiji were protected rather than deforested. Finally, we determine the priority of each coral reef for implementing a marine protected area when all remnant forest is protected for conservation. The general results will support decisions made by the Fiji Protected Area Committee as they establish a national protected area network that aims to protect 20% of the land and 30% of the inshore waters by 2020. Although challenges remain, we can inform conservation decisions around the globe by tackling the complex issues relevant to integrated land-sea planning.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Arrecifes de Coral , Árboles , Animales , Análisis Costo-Beneficio , Fiji , Explotaciones Pesqueras , Peces , Actividades Humanas , Contaminantes Químicos del Agua
18.
PLoS One ; 6(11): e26339, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22073157

RESUMEN

There has been substantial recent change in coral reef communities. To date, most analyses have focussed on static patterns or changes in single variables such as coral cover. However, little is known about how community-level changes occur at large spatial scales. Here, we develop Markov models of annual changes in coral and macroalgal cover in the Caribbean and Great Barrier Reef (GBR) regions. We analyzed reef surveys from the Caribbean and GBR (1996-2006). We defined a set of reef states distinguished by coral and macroalgal cover, and obtained Bayesian estimates of the annual probabilities of transitions between these states. The Caribbean and GBR had different transition probabilities, and therefore different rates of change in reef condition. This could be due to differences in species composition, management or the nature and extent of disturbances between these regions. We then estimated equilibrium probability distributions for reef states, and coral and macroalgal cover under constant environmental conditions. In both regions, the current distributions are close to equilibrium. In the Caribbean, coral cover is much lower and macroalgal cover is higher at equilibrium than in the GBR. We found no evidence for differences in transition probabilities between the first and second halves of our survey period, or between Caribbean reefs inside and outside marine protected areas. However, our power to detect such differences may have been low. We also examined the effects of altering transition probabilities on the community state equilibrium, along a continuum from unfavourable (e.g., increased sea surface temperature) to favourable (e.g., improved management) conditions. Both regions showed similar qualitative responses, but different patterns of uncertainty. In the Caribbean, uncertainty was greatest about effects of favourable changes, while in the GBR, we are most uncertain about effects of unfavourable changes. Our approach could be extended to provide risk analysis for management decisions.


Asunto(s)
Antozoos , Animales , Teorema de Bayes , Probabilidad
19.
PLoS One ; 5(2): e9278, 2010 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-20174644

RESUMEN

BACKGROUND: A variety of human activities have led to the recent global decline of reef-building corals. The ecological, social, and economic value of coral reefs has made them an international conservation priority. The success of Marine Protected Areas (MPAs) in restoring fish populations has led to optimism that they could also benefit corals by indirectly reducing threats like overfishing, which cause coral degradation and mortality. However, the general efficacy of MPAs in increasing coral reef resilience has never been tested. METHODOLOGY/PRINCIPAL FINDINGS: We compiled a global database of 8534 live coral cover surveys from 1969-2006 to compare annual changes in coral cover inside 310 MPAs to unprotected areas. We found that on average, coral cover within MPAs remained constant, while coral cover on unprotected reefs declined. Although the short-term differences between unprotected and protected reefs are modest, they could be significant over the long-term if the effects are temporally consistent. Our results also suggest that older MPAs were generally more effective in preventing coral loss. Initially, coral cover continued to decrease after MPA establishment. Several years later, however, rates of coral cover decline slowed and then stabilized so that further losses stopped. CONCLUSIONS/SIGNIFICANCE: These findings suggest that MPAs can be a useful tool not only for fisheries management, but also for maintaining coral cover. Furthermore, the benefits of MPAs appear to increase with the number of years since MPA establishment. Given the time needed to maximize MPA benefits, there should be increased emphasis on implementing new MPAs and strengthening the enforcement of existing MPAs.


Asunto(s)
Antozoos/crecimiento & desarrollo , Conservación de los Recursos Naturales/métodos , Ecosistema , Monitoreo del Ambiente/métodos , Animales , Biodiversidad , Región del Caribe , Explotaciones Pesqueras/métodos , Peces/crecimiento & desarrollo , Geografía , Humanos , Océano Índico , Biología Marina , Océano Pacífico , Densidad de Población , Medición de Riesgo
20.
Ecology ; 90(6): 1478-84, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19569362

RESUMEN

Many marine scientists have concluded that coral reefs are moving toward or are locked into a seaweed-dominated state. However, because there have been no regional- or global-scale analyses of such coral reef "phase shifts," the magnitude of this phenomenon was unknown. We analyzed 3581 quantitative surveys of 1851 reefs performed between 1996 and 2006 to determine the frequency, geographical extent, and degree of macroalgal dominance of coral reefs and of coral to macroalgal phase shifts around the world. Our results indicate that the replacement of corals by macroalgae as the dominant benthic functional group is less common and less geographically extensive than assumed. Although we found evidence of moderate local increases in macroalgal cover, particularly in the Caribbean, only 4% of reefs were dominated by macroalgae (i.e., > 50% cover). Across the Indo-Pacific, where regional averages of macroalgal cover were 9-12%, macroalgae only dominated 1% of the surveyed reefs. Between 1996 and 2006, phase shift severity decreased in the Caribbean, did not change in the Florida Keys and Indo-Pacific, and increased slightly on the Great Barrier Reef due to moderate coral loss. Coral reef ecosystems appear to be more resistant to macroalgal blooms than assumed, which has important implications for reef management.


Asunto(s)
Antozoos/fisiología , Ecosistema , Eucariontes/fisiología , Animales , Región del Caribe , Océano Pacífico , Dinámica Poblacional
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