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1.
Mol Ecol ; 33(12): e17373, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703047

RESUMO

Coastal areas host a major part of marine biodiversity but are seriously threatened by ever-increasing human pressures. Transforming natural coastlines into urban seascapes through habitat artificialization may result in loss of biodiversity and key ecosystem functions. Yet, the extent to which seaports differ from nearby natural habitats and marine reserves across the whole Tree of Life is still unknown. This study aimed to assess the level of α and ß-diversity between seaports and reserves, and whether these biodiversity patterns are conserved across taxa and evolutionary lineages. For that, we used environmental DNA (eDNA) metabarcoding to survey six seaports on the French Mediterranean coast and four strictly no-take marine reserves nearby. By targeting four different groups-prokaryotes, eukaryotes, metazoans and fish-with appropriate markers, we provide a holistic view of biodiversity on contrasted habitats. In the absence of comprehensive reference databases, we used bioinformatic pipelines to gather similar sequences into molecular operational taxonomic units (MOTUs). In contrast to our expectations, we obtained no difference in MOTU richness (α-diversity) between habitats except for prokaryotes and threatened fishes with higher diversity in reserves than in seaports. However, we observed a marked dissimilarity (ß-diversity) between seaports and reserves for all taxa. Surprisingly, this biodiversity signature of seaports was preserved across the Tree of Life, up to the order. This result reveals that seaports and nearby marine reserves share few taxa and evolutionary lineages along urbanized coasts and suggests major differences in terms of ecosystem functioning between both habitats.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , DNA Ambiental , Ecossistema , Peixes , Animais , DNA Ambiental/genética , Peixes/genética , Peixes/classificação , Conservação dos Recursos Naturais , França , Organismos Aquáticos/genética , Organismos Aquáticos/classificação , Filogenia
2.
Glob Chang Biol ; 30(1): e17113, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273578

RESUMO

Seagrass is an important natural attribute of 28 World Heritage (WH) properties. These WH seagrass habitats provide a wide range of services to adjacent ecosystems and human communities, and are one of the largest natural carbon sinks on the planet. Climate change is considered the greatest and fastest-growing threat to natural WH properties and evidence of climate-related impacts on seagrass habitats has been growing. The main objective of this study was to assess the vulnerability of WH seagrass habitats to location-specific key climate stressors. Quantitative surveys of seagrass experts and site managers were used to assess exposure, sensitivity and adaptive capacity of WH seagrass habitats to climate stressors, following the Climate Vulnerability Index approach. Over half of WH seagrass habitats have high vulnerability to climate change, mainly from the long-term increase in sea-surface temperature and short-term marine heatwaves. Potential impacts from climate change and certainty scores associated with them were higher than reported by a similar survey-based study from 10 years prior, indicating a shift in stakeholder perspectives during the past decade. Additionally, seagrass experts' opinions on the cumulative impacts of climate and direct-anthropogenic stressors revealed that high temperature in combination with high suspended sediments, eutrophication and hypoxia is likely to provoke a synergistic cumulative (negative) impact (p < .05). A key component contributing to the high vulnerability assessments was the low adaptive capacity; however, discrepancies between adaptive capacity scores and qualitative responses suggest that managers of WH seagrass habitats might not be adequately equipped to respond to climate change impacts. This thematic assessment provides valuable information to help prioritize conservation actions, monitoring activities and research in WH seagrass habitats. It also demonstrates the utility of a systematic framework to evaluate the vulnerability of thematic groups of protected areas that share a specific attribute.


Assuntos
Mudança Climática , Ecossistema , Humanos , Temperatura , Sequestro de Carbono , Eutrofização
3.
J Fish Biol ; 104(5): 1628-1632, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38332477

RESUMO

Recent encounters with sicklefin (Mobula tarapacana) and bentfin (Mobula thurstoni) devil rays in the Chagos Archipelago provide the first confirmed observations of live specimens of these species in this region. Examination of illegal fishing photo archives collected during enforcement revealed these endangered species, and spinetail devil rays (Mobula mobular), are being caught within the archipelago's vast no-take marine protected area. Future cooperation between authorities and mobulid ray experts is crucial to improve the availability and accuracy of enforcement data and improve management of illegal fishing and mobulid ray conservation activities.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Rajidae , Animais
4.
J Fish Biol ; 104(5): 1645-1650, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38402691

RESUMO

Areas of importance to Southern Ocean skates are poorly defined. Here, we identify a deepwater skate egg case nursery in a discrete location at ~460 m depth off Cape Adare in the Southern Ocean. This is the first confirmed observation of a skate nursery area in the Ross Sea and only the second observation for the Southern Ocean. The morphology and size of the egg cases were consistent with the genus Bathyraja and most likely belong to the Bathyraja sp. (cf. eatonii). The nursery occurs within the "no take" General Protection Zone of the Ross Sea region marine protected area, where commercial fishing is prohibited.


Assuntos
Oceanos e Mares , Óvulo , Rajidae , Animais , Feminino
5.
J Environ Manage ; 355: 120476, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38442657

RESUMO

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.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Biomassa , Ecossistema , Pesqueiros , Peixes/fisiologia , Oceanos e Mares , Inquéritos e Questionários
6.
Glob Chang Biol ; 29(19): 5634-5651, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37439293

RESUMO

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.


Assuntos
Ecossistema , Kelp , Animais , Conservação dos Recursos Naturais/métodos , Biomassa , Invertebrados , Florestas , Peixes
7.
Ecol Appl ; 33(7): e2895, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37282356

RESUMO

Trophic downgrading destabilizes ecosystems and can drive large-scale shifts in ecosystem state. While restoring predatory interactions in marine reserves can reverse anthropogenic-driven shifts, empirical evidence of increased ecosystem stability and persistence in the presence of predators is scant. We compared temporal variation in rocky reef ecosystem state in New Zealand's oldest marine reserve to nearby fished reefs to examine whether protection of predators led to more persistent and stable reef ecosystem states in the marine reserve. Contrasting ecosystem states were found between reserve and fished sites, and this persisted over the 22-year study period. Fished sites were predominantly urchin barrens but occasionally fluctuated to short-lived turfs and mixed algal forests, while reserve sites displayed unidirectional successional trajectories toward stable kelp forests (Ecklonia radiata) taking up to three decades following protection. This provides empirical evidence that long-term protection of predators facilitates kelp forest recovery, resists shifts to denuded alternate states, and enhances kelp forest stability.


Assuntos
Ecossistema , Kelp , Animais , Cadeia Alimentar , Ouriços-do-Mar , Florestas
8.
J Fish Biol ; 102(1): 172-177, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36226898

RESUMO

The recently described Lutz's stingray Hypanus berthalutzae is endemic to the Brazilian Province, including oceanic islands. Although it is expected to have life-history traits similar to the southern stingray H. americanus, little is known about its reproductive biology. Here we present the first observations of courtship behaviour (n = 4), copulation (n = 3) and an induced parturition of H. berthalutzae at the Fernando de Noronha Archipelago, an insular Marine Protected Area from the Equatorial Atlantic Ocean. The mating event records included (1) 'chasing/close following', (2) 'biting/precopulatory biting', (3) 'insertion/copulation' and (4) 'separation'. These results are especially relevant considering that records of reproductive behaviour in the wild are rare for elasmobranchs in general. Mating events occurred in different months, suggesting that the reproductive cycle of H. berthalutzae in this insular system is asynchronous, as observed for other stingray species in regions with favourable environmental conditions and abundant food throughout the year. The opportunistic documentation of the induced parturition allowed for direct nonlethal observation of the two pups at or near full term in late May. Although preliminary, these observations should be considered in future management plans as they provide relevant data about the life-history traits and mating behaviour of this endemic and threatened species.


Assuntos
Elasmobrânquios , Rajidae , Animais , Gravidez , Feminino , Brasil , Parto
9.
Conserv Biol ; 36(6): e13977, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35866368

RESUMO

Small-scale fisheries account for 90% of global fishers and 40% of the global catch. Effectively managing small-scale fisheries is, therefore, crucial to progressing the United Nations Sustainable Development Goals (SDGs). Co-management and community-based fisheries management are widely considered the most appropriate forms of governance for many small-scale fisheries. We outlined relationships between small-scale fisheries co-management and attainment of the SDGs, including evidence for impacts and gaps in dominant logic. We identified 11 targets across five SDGs to which small-scale fisheries co-management (including community-based fisheries management) can contribute; the theory of change by which these contributions could be achieved; and the strength of evidence for progress toward SDG targets related to various co-management strategies. Our theory of change links the 11 SDG targets by qualifying that progress toward some targets is contingent on others being achieved first. We then reviewed 58 case studies of co-management impacts from the Pacific Islands--a region rich in local marine governance--to evaluate evidence of where, to what degree, and with how much certainty different co-management strategies conferred positive impacts to each SDG target. These strategies included access restrictions, permanent area closures, periodic closures, and gear and species restrictions. Although many studies provide evidence linking multiple co-management strategies to improvements in resource status (SDG 14.4), there was limited evidence of follow-on effects, such as improvements in catch (SDG 2.3, 2.4), livelihoods (SDG 1.2), consumption (SDG 2.1), and nutrition (SDG 2.2). Our findings suggest that leaps of logic and assumptions are prevalent in co-management planning and evaluation. Hence, when evaluating co-management impacts against the SDGs, consideration of ultimate goals is required, otherwise, there is a risk of shortfalls between aspirations and impact.


Las pequeñas pesquerías representan el 90% de los pescadores y el 40% de la pesca a nivel mundial. Por lo tanto, su manejo efectivo es crucial para el avance de los Objetivos de Desarrollo Sustentable de las Naciones Unidas (ODS). Generalmente se considera a la coadministración y la administración comunitaria de las pesquerías como las maneras más apropiadas para gestionar las pequeñas pesquerías. Perfilamos las relaciones entre la coadministración de estas pesquerías y la obtención de los ODS, incluida la evidencia de impactos y vacíos en la lógica dominante. Identificamos once metas en cinco ODS a las cuales puede contribuir la coadministración de las pequeñas pesquerías (incluyendo la administración comunitaria de las pesquerías); la teoría de cambio mediante la cual pueden lograrse estas contribuciones; y la solidez de la evidencia relacionada con varias estrategias de coadministración para el progreso hacia las metas de los ODS. Nuestra teoría de cambio conecta a las once metas de los ODS al calificar que el progreso hacia algunas metas está supeditado a que primero se logren otras metas. Después revisamos 58 estudios de caso del impacto de la coadministración en las islas del Pacífico - una región rica en gestión marina local - para evaluar la evidencia de dónde, a cuál grado y con cuánta certeza las diferentes estrategias de coadministración otorgaron impactos positivos a cada meta de los ODS. Estas estrategias incluyen restricciones de acceso, cierres permanentes del área, cierres periódicos y restricciones de equipamiento y especies. Mientras que muchos estudios proporcionaron evidencia que conecta a varias estrategias de coadministración con mejoras en el estado de los recursos (ODS 14.4), hubo pruebas limitadas de los efectos de seguimiento, como mejoras en la captura (ODS 2.3, 2.4), la subsistencia (ODS 1.2), el consumo (ODS 2.1) y la nutrición (ODS 2.2). Nuestros descubrimientos sugieren que los saltos de lógica y de suposición prevalecen en la planeación y evaluación de la coadministración.


Assuntos
Pesqueiros , Desenvolvimento Sustentável , Conservação dos Recursos Naturais , Nações Unidas , Estudos Retrospectivos
10.
J Environ Manage ; 320: 115829, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36056482

RESUMO

Stony corals play a key role in the marine biodiversity of many tropical coastal areas as suppliers of substrate, food and shelter for other reef organisms. Therefore, it is remarkable that coral diversity usually does not play a role in the planning of protected areas in coral reef areas. In the present study we examine how stony coral diversity patterns relate to marine park zonation and the economic value of reefs around St. Eustatius, a small island in the eastern Caribbean, with fisheries and tourism as important sources of income. The marine park contains two no-take reserves. A biodiversity survey was performed at 39 sites, 24 inside the reserves and 15 outside; 22 had a maximum depth >18 m and 17 were shallower. Data on economic value per site were obtained from the literature. Corals were photographed for the verification of identifications made in the field. Coral species richness (n = 49) was highest in the no-take reserves and species composition was mainly affected by maximum depth. No distinct relation is observed between coral diversity and fishery value or total economic value. Based on the outcome of this study we suggest that in future designs of marine park zonation in reef areas, coral diversity should be taken into consideration. This is best served by including reef areas with a continuous depth gradient from shallow flats to deep slopes.


Assuntos
Antozoários , Recifes de Corais , Animais , Biodiversidade , Região do Caribe , Ecossistema , Pesqueiros
11.
J Environ Manage ; 308: 114633, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35124307

RESUMO

Costa Rica is one of the most biodiverse countries in the world, and stands out for its commitment to conservation. Along its two coasts, it presents a great heterogeneity of ecosystems and social realities. Social factors, more than physical-natural factors, determine the success or failure of an MPA, so they must be urgently incorporated into all phases of MPA management. The objective of this work is to analyze the management of three marine protected areas, to establish improvements. These areas are Santa Rosa National Park, Marino Ballena National Park and Cahuita National Park. The methodology used assesses 26 indicators grouped into 4 key factotres: management body, planning subprocess, public participation, and implementation subprocess. The results of this evaluation are 5 possible scenarios. These scenarios have been termed (from the ideal situation to the least favourable): proactive (1), learning (2), interactive (3), centralized (4) and formal (5) management. The results of this study show that both Santa Rosa and Cahuita present a proactive scenario (1), with high citizen participation, although in practice the way the two MPAs are managed is very different. Marino Ballena, on the other hand, is in scenario 5 (formal), and a series of measures are presented that can move it towards scenario 2 (learning). In general, MPA management in Costa Rica tends to be adaptive, with high public participation, as determined by its public policies. However, the existence of a public policy favors but does not guarantee success in MPA management, as can be seen in the difference in results. Therefore, the periodic evaluation of its management, allowing for feedback, is essential.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Costa Rica , Parques Recreativos
12.
Environ Dev Sustain ; : 1-27, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35571997

RESUMO

Tourism is one of the most important issues facing marine protected areas (MPAs) and small islands worldwide. Tourism development is considered a contribution to pollution levels in the environment. This paper aims to evaluate the hypothetical effects of tourism development on water quality spatially and temporally using the coastal water quality index (CWQI) and Geographic Information System (GIS) in search of improved management for marine conservation areas. This study showed significant tourism influences on the CWQI in the Marine Tourism Park of the Gili Matra Islands, Lombok, Indonesia. Water quality variability indicates a significant spatiotemporal difference (p < 0.05) in the two tourism seasons. During the peak season of tourism, the CWQI decreased to poor conditions, i.e., ranging from 9.95 to 21.49 for marine biota and from 7.98 to 30.42 for marine tourism activities in 2013, and ranging from 39.52 to 44.42 for marine biota and from 44.13 to 47.28 for marine tourism activities, which were below the standard for both marine biota and marine tourism activities. On the contrary, it showed a better level (from poor to moderate) during the low season of tourism (ranging from 41.92 to 61.84 for marine biota and from 48.06 to 65.27 for marine tourism activities in 2014), providing a more acceptable condition for both aspects. The study proved that massive tourism development in the MPA and small islands could reduce water quality and increase vulnerability. Accordingly, integrated tourism management and the environment, waters, and land will be needed to develop sustainable tourism. The CWQI and GIS were applicable to assess water quality, both spatially and temporally, and become a quick reference in monitoring and initial evaluation of impact management.

13.
Glob Chang Biol ; 27(17): 3956-3968, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34021662

RESUMO

Intensified coastal development is compromising the health and functioning of marine ecosystems. A key example of this is the Red Sea, a biodiversity hotspot subjected to increasing local human pressures. While some marine-protected areas (MPAs) were placed to alleviate these stressors, it is unclear whether these MPAs are managed or enforced, thus providing limited protection. Yet, most importantly, MPAs in the Red Sea were not designed using climate considerations, likely diminishing their effectiveness against global stressors. Here, we propose to tailor the design of MPAs in the Red Sea by integrating approaches to enhance climate change mitigation and adaptation. First, including coral bleaching susceptibility could produce a more resilient network of MPAs by safeguarding reefs from different thermal regions that vary in spatiotemporal bleaching responses, reducing the risk that all protected reefs will bleach simultaneously. Second, preserving the basin-wide genetic connectivity patterns that are assisted by mesoscale eddies could further ensure recovery of sensitive populations and maintain species potential to adapt to environmental changes. Finally, protecting mangrove forests in the northern and southern Red Sea that act as major carbon sinks could help offset greenhouse gas emissions. If implemented with multinational cooperation and concerted effort among stakeholders, our portfolio of climate-tailored approaches may help build a network of MPAs in the Red Sea that protects more effectively its coastal resources against escalating coastal development and climate instability. Beyond the Red Sea, we anticipate this study to serve as an example of how to improve the utility of tropical MPAs as climate-informed conservation tools.


Assuntos
Antozoários , Ecossistema , Animais , Biodiversidade , Conservação dos Recursos Naturais , Recifes de Corais , Humanos , Oceano Índico
14.
Glob Chang Biol ; 27(21): 5514-5531, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34486773

RESUMO

Marine spatial planning that addresses ocean climate-driven change ('climate-smart MSP') is a global aspiration to support economic growth, food security and ecosystem sustainability. Ocean climate change ('CC') modelling may become a key decision-support tool for MSP, but traditional modelling analysis and communication challenges prevent their broad uptake. We employed MSP-specific ocean climate modelling analyses to inform a real-life MSP process; addressing how nature conservation and fisheries could be adapted to CC. We found that the currently planned distribution of these activities may become unsustainable during the policy's implementation due to CC, leading to a shortfall in its sustainability and blue growth targets. Significant, climate-driven ecosystem-level shifts in ocean components underpinning designated sites and fishing activity were estimated, reflecting different magnitudes of shifts in benthic versus pelagic, and inshore versus offshore habitats. Supporting adaptation, we then identified: CC refugia (areas where the ecosystem remains within the boundaries of its present state); CC hotspots (where climate drives the ecosystem towards a new state, inconsistent with each sectors' present use distribution); and for the first time, identified bright spots (areas where oceanographic processes drive range expansion opportunities that may support sustainable growth in the medium term). We thus create the means to: identify where sector-relevant ecosystem change is attributable to CC; incorporate resilient delivery of conservation and sustainable ecosystem management aims into MSP; and to harness opportunities for blue growth where they exist. Capturing CC bright spots alongside refugia within protected areas may present important opportunities to meet sustainability targets while helping support the fishing sector in a changing climate. By capitalizing on the natural distribution of climate resilience within ocean ecosystems, such climate-adaptive spatial management strategies could be seen as nature-based solutions to limit the impact of CC on ocean ecosystems and dependent blue economy sectors, paving the way for climate-smart MSP.


Assuntos
Mudança Climática , Ecossistema , Adaptação Fisiológica , Conservação dos Recursos Naturais , Pesqueiros , Oceanografia
15.
Ecol Appl ; 31(1): e2213, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750738

RESUMO

Human activities and land-use drivers combine in complex ways to affect coral reef health and, in turn, the diversity and abundance of reef fauna. Here we examine the impacts of different marine protected area (MPA) types, and various human and habitat drivers, on resource fish functional groups (i.e., total fish, herbivore, grazer, scraper, and browser biomass) along the 180 km west coast of Hawaii Island. Across survey years from 2008 to 2018, we observed an overall decrease in total fish biomass of 45%, with similar decreases in biomass seen across most fish functional groups. MPAs that prohibited a combination of lay nets, aquarium collection, and spear fishing were most effective in maintaining and/or increasing fish biomass across all functional groups. We also found that pollution, fishing, and habitat drivers all contributed to changes in total fish biomass, where the most negative impact was nitrogen input from land-based sewage disposal. Fish biomass relationships with our study drivers depended on fish functional grouping. For surgeonfish (grazers), changes in biomass linked most strongly to changes in reef rugosity. For parrotfish (scrapers), biomass was better explained by changes in commercial catch where current commercial fishing levels are negatively affecting scraper populations. Our observations suggest that regional management of multiple factors, including habitat, pollution, and fisheries, will benefit resource fish biomass off Hawaii Island.


Assuntos
Conservação dos Recursos Naturais , Recifes de Corais , Animais , Biomassa , Ecossistema , Pesqueiros , Peixes , Havaí , Humanos
16.
Ecol Appl ; 31(6): e02364, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33899297

RESUMO

An ultimate benefit of marine protected areas (MPAs) is to reverse trophic cascades caused by human-driven collapse of critical ecological interactions. Here we demonstrate that, despite a small scale (0.28 km2 ) and not being fully protected, an MPA with strict fishing management and habitat enhancement by artificial reefs (ARs) in southwest Japan can lead to well-established macroalgal communities on widespread sea urchin barrens through cascading effects of predator recovery. Areas with low urchin densities occurred in and around daytime lobster (Panulirus japonicus) shelters primarily formed by quarry-rock ARs inside the MPA. We confirmed in the laboratory that lobsters preyed on two dominant sea urchins (Echinometra sp. A and Heliocidaris crassispina), with size- and species-dependent predation. The area with few urchins extended farther (˜65 m) from an AR with numerous lobsters than from a natural shelter (patch reef) with far fewer lobsters. Causation of this pattern was confirmed by a tethering experiment showing that predation on urchins was similarly high at and near lobster shelters but decreased at ˜100 m from the AR to a similar level as at an unprotected site. Time-lapse photography revealed that predation on tethered urchins was due mostly to the largest size class of lobsters (>100 mm carapace length), which comprised only 7% of the population, highlighting the importance of large-sized lobsters in controlling urchin abundance in localized areas adjacent to urchin-dominated barrens. Despite an ongoing once-a-year fishing event permitted within the MPA, lobster populations were persistent, demonstrating that the cascading effect of the lobsters on urchins and ultimately macroalgae was robust to temporary reductions in predator population size. Erect macroalgal cover was not simply accounted for by snapshot urchin density or biomass, suggesting a hysteresis effect of the phase shifts between macroalgal dominance and urchin barren states.


Assuntos
Cadeia Alimentar , Palinuridae , Comportamento Predatório , Ouriços-do-Mar , Animais , Ecossistema
17.
Conserv Biol ; 35(4): 1222-1232, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33314325

RESUMO

Mapping and predicting the potential risk of fishing activities to large marine protected areas (MPAs), where management capacity is low but fish biomass may be globally important, is vital to prioritizing enforcement and maximizing conservation benefits. Drifting fish aggregating devices (dFADs) are a highly effective fishing method employed in purse seine fisheries that attract and accumulate biomass fish, making fish easier to catch. However, dFADs are associated with several negative impacts, including high bycatch rates and lost or abandoned dFADs becoming beached on sensitive coastal areas (e.g., coral reefs). Using Lagrangian particle modeling, we determined the potential transit of dFADs in a large MPA around the Chagos Archipelago in the central Indian Ocean. We then quantified the risk of dFADs beaching on the archipelago's reefs and atolls and determined the potential for dFADs to pass through the MPA, accumulate biomass while within, and export it into areas where it can be legally fished (i.e., transit). Over one-third (37.51%) of dFADs posed a risk of either beaching or transiting the MPA for >14 days, 17.70% posed a risk of beaching or transiting the MPA for >30 days, and 13.11% posed a risk of beaching or transiting the MPA for >40 days. Modeled dFADs deployed on the east and west of the perimeter were more likely to beach and have long transiting times (i.e., posed the highest risk). The Great Chagos Bank, the largest atoll in the archipelago, was the most likely site to be affected by dFADs beaching. Overall, understanding the interactions between static MPAs and drifting fishing gears is vital to developing suitable management plans to support enforcement of MPA boundaries and the functioning and sustainability of their associated biomass.


Riesgos para las Grandes Áreas Marinas Protegidas Ocasionados por los Dispositivos Agregadores de Peces a la Deriva Resumen El mapeo y la predicción del riesgo potencial que las actividades de pesca representan para las grandes áreas marinas (AMP), en donde la capacidad de manejo es baja pero la biomasa de peces puede ser de importancia global, son vitales para priorizar la aplicación y maximizar los beneficios de conservación. Los dispositivos agregadores de peces a la deriva (DAPds) son un método de pesca altamente efectivo y empleado en las pesquerías de redes de cerco. Estos dispositivos atraen y acumulan biomasa de peces, facilitando así la captura de peces. Sin embargo, los DAPd están asociados con varios impactos negativos, incluyendo tasas altas de captura accesoria y DAPd perdidos o abandonados que terminan varados en áreas costeras sensibles (p. ej.: arrecifes de coral). Mediante el modelado de partículas langrangianas, determinamos el tránsito potencial de los DAPd en una AMP grande alrededor del Archipiélago Chagos en el centro del Océano Índico. Después cuantificamos el riesgo de varamiento de los DAPd en los arrecifes y atolones del arrecife y determinamos el potencial que tienen los DAPd de pasar por la AMP, acumular biomasa durante el trayecto y exportarla a áreas en las que es legal su pesca (es decir, transitar). Más de un tercio (37.51%) de los DAPd representaron un riesgo de varamiento o tránsito a través de la AMP durante >14 días y el 17.70% representó un riesgo de varamiento o tránsito a través de la AMP durante >40 días. Los DAPd modelados desplegados en el este y en el oeste del perímetro tuvieron mayor probabilidad de varamiento o de tener tiempos de tránsito largos (es decir, representaron el riesgo más alto). El Gran Banco de Chagos, el atolón más grande en el archipiélago, fue el sitio con mayor probabilidad de ser afectado por el varamiento de los DAPd. En general, el entendimiento de las interacciones entre las AMP estáticas y el equipo de pesca a la deriva es vital para el desarrollo de planes de manejo adecuados para respaldar el cumplimiento de los límites de las AMP y el funcionamiento y sostenibilidad de la biomasa asociada a ellas.


Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Animais , Biomassa , Recifes de Corais , Peixes , Oceano Índico
18.
Conserv Biol ; 35(3): 909-920, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32785955

RESUMO

The availability of genomic data for an increasing number of species makes it possible to incorporate evolutionary processes into conservation plans. Recent studies show how genetic data can inform spatial conservation prioritization (SCP), but they focus on metrics of diversity and distinctness derived primarily from neutral genetic data sets. Identifying adaptive genetic markers can provide important information regarding the capacity for populations to adapt to environmental change. Yet, the effect of including metrics based on adaptive genomic data into SCP in comparison to more widely used neutral genetic metrics has not been explored. We used existing genomic data on a commercially exploited species, the giant California sea cucumber (Parastichopus californicus), to perform SCP for the coastal region of British Columbia (BC), Canada. Using a RAD-seq data set for 717 P. californicus individuals across 24 sampling locations, we identified putatively adaptive (i.e., candidate) single nucleotide polymorphisms (SNPs) based on genotype-environment associations with seafloor temperature. We calculated various metrics for both neutral and candidate SNPs and compared SCP outcomes with independent metrics and combinations of metrics. Priority areas varied depending on whether neutral or candidate SNPs were used and on the specific metric used. For example, targeting sites with a high frequency of warm-temperature-associated alleles to support persistence under future warming prioritized areas in the southern coastal region. In contrast, targeting sites with high expected heterozygosity at candidate loci to support persistence under future environmental uncertainty prioritized areas in the north. When combining metrics, all scenarios generated intermediate solutions, protecting sites that span latitudinal and thermal gradients. Our results demonstrate that distinguishing between neutral and adaptive markers can affect conservation solutions and emphasize the importance of defining objectives when choosing among various genomic metrics for SCP.


Incorporación de Datos Genómicos Putativamente Neutros y Adaptativos dentro de la Planeación de la Conservación Marina Resumen La disponibilidad de los datos genómicos para un número creciente de especies posibilita la incorporación de los procesos evolutivos dentro de los planes de conservación. Los estudios recientes muestran cómo los datos genéticos pueden informar a la priorización de la conservación espacial (PCE) pero tienden a enfocarse más en las medidas de la diversidad y la distinción derivadas principalmente de los conjuntos de datos genéticos neutrales. La identificación de los marcadores genéticos adaptativos puede proporcionar información importante con respecto a la capacidad de las poblaciones para adaptarse al cambio ambiental. Aun así, no se ha explorado el efecto de la inclusión de las medidas basadas en los datos genéticos adaptativos dentro de la PCE y cómo se comparan con las medidas genéticas neutrales de uso más amplio. Usamos datos genómicos existentes sobre una especie de explotación comercial, el pepino de mar gigante de California (Parastichopus californicus), para realizar la PCE para la región costera de la Columbia Británica (BC) en Canadá. Usamos un conjunto de datos RAD-seq para 717 individuos de la especie P. californicus en 24 localidades de muestreo para identificar los polimorfismos de un solo nucleótido (PSNs) putativamente adaptativos (es decir, candidatos) con base en las asociaciones genotipo-ambiente manifestadas con la temperatura del fondo marino. Calculamos varias medidas para los PSNs neutrales y los PSNs candidatos y comparamos los resultados de la PCE con medidas independientes y con combinaciones de medidas. Las áreas prioritarias variaron dependiendo de si se usaron los SNP neutrales o los candidatos y de la medida específica que se utilizó. Por ejemplo, enfocarse en sitios con una frecuencia alta de alelos asociados con agua cálida para fortalecer la persistencia frente al futuro calentamiento prioriza las áreas en la región del sur de la costa. Al contrario, enfocarse en sitios con una alta heterocigosidad esperada en los loci de los candidatos para fortalecer la persistencia frente a la incertidumbre ambiental prioriza las áreas en la parte norte de la costa. Cuando combinamos las medidas, todos los escenarios generaron soluciones intermedias, protegiendo así los sitios que abarcan gradientes latitudinales y gradientes térmicos. Nuestros resultados demuestran que la distinción entre los marcadores neutrales y los adaptativos puede afectar las soluciones de conservación y también enfatizan la importancia de la definición de los objetivos cuando se elige entre varias medidas genómicas para la PCE.


Assuntos
Conservação dos Recursos Naturais , Genômica , Evolução Biológica , Colúmbia Britânica , Genótipo , Humanos
19.
Conserv Biol ; 35(6): 1861-1870, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34190357

RESUMO

Marine protected areas (MPAs) cover 3-7% of the world's ocean, and international organizations call for 30% coverage by 2030. Although numerous studies show that MPAs produce conservation benefits inside their borders, many MPAs are also justified on the grounds that they confer conservation benefits to the connected populations that span beyond their borders. A network of MPAs covering roughly 20% of the Channel Islands National Marine Sanctuary was established in 2003, with a goal of providing regional conservation and fishery benefits. We used a spatially explicit bioeconomic simulation model and a Bayesian difference-in-difference regression to examine the conditions under which MPAs can provide population-level conservation benefits inside and outside their borders and to assess evidence of those benefits in the Channel Islands. As of 2017, we estimated that biomass densities of targeted fin-fish had a median value 81% higher (90% credible interval: 23-148) inside the Channel Island MPAs than outside. However, we found no clear effect of these MPAs on mean total biomass densities at the population level: estimated median effect was -7% (90% credible interval: -31 to 23) from 2015 to 2017. Our simulation model showed that effect sizes of MPAs of <30% were likely to be difficult to detect (even when they were present); smaller effect sizes (which are likely to be common) were even harder to detect. Clearly, communicating expectations and uncertainties around MPAs is critical to ensuring that MPAs are effective. We provide a novel assessment of the population-level effects of a large MPA network across many different species of targeted fin-fish, and our results offer guidance for communities charged with monitoring and adapting MPAs.


Las áreas marinas protegidas (AMPs) cubren entre 3-7% de los océanos del planeta y las organizaciones internacionales piden una cobertura del 30% para el 2030. Aunque numerosos estudios muestran que las AMPs producen beneficios de conservación dentro de sus límites, muchas de estas áreas también están justificadas por otorgarles beneficios de conservación a las poblaciones conectadas que abarcan más allá de sus fronteras. Una red de AMPs que cubre aproximadamente el 20% del Santuario Marino Nacional de las Islas del Canal fue establecida en 2003 con el objetivo de proporcionar beneficios para la conservación y las pesquerías regionales. Usamos un modelo de simulación bioeconómica espacialmente explícito y una regresión bayesiana de diferencia-en-diferencia para examinar las condiciones bajo las que las AMPs pueden proporcionar beneficios de conservación a nivel poblacional dentro y fuera de sus límites y para evaluar las evidencias de esos beneficios en las Islas del Canal. Hasta el 2017, estimamos que la densidad de la biomasa de los peces focalizados tuvo un valor medio de 81% (90% intervalo creíble 23-148) dentro de las AMPs de las Islas del Canal que fuera de ellas. Sin embargo, no encontramos un efecto claro de estas AMPs sobre la densidad de biomasa total promedio a nivel poblacional; el efecto medio estimado fue de -7% (90% intervalo creíble -31 - 23) entre 2015 y 2017. Nuestro modelo de simulación mostró que los tamaños del efecto de las AMPs menores al 30% tenían mayor probabilidad de ser difíciles de detectar (incluso cuando estaban presentes); los tamaños de efecto más pequeños (que es probable que sean comunes) fueron incluso más difíciles de detectar. Claramente, es muy importante comunicar las expectativas e incertidumbres en torno a las AMPs para asegurar que éstas sean efectivas. Proporcionamos una evaluación novedosa de los efectos a nivel poblacional de una red extensa de AMPs para muchas especies de peces focalizados y nuestros resultados ofrecen una guía para las comunidades encargadas de monitorear y adaptar las AMPs.


Assuntos
Conservação dos Recursos Naturais , Pesqueiros , Animais , Teorema de Bayes , Peixes
20.
Conserv Biol ; 35(6): 1944-1956, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34224158

RESUMO

Assessing the impact of global changes and protection effectiveness is a key step in monitoring marine fishes. Most traditional census methods are demanding or destructive. Nondisturbing and nonlethal approaches based on video and environmental DNA are alternatives to underwater visual census or fishing. However, their ability to detect multiple biodiversity factors beyond traditional taxonomic diversity is still unknown. For bony fishes and elasmobranchs, we compared the performance of eDNA metabarcoding and long-term remote video to assess species' phylogenetic and functional diversity. We used 10 eDNA samples from 30 L of water each and 25 hr of underwater videos over 4 days on Malpelo Island (pacific coast of Colombia), a remote marine protected area. Metabarcoding of eDNA detected 66% more molecular operational taxonomic units (MOTUs) than species on video. We found 66 and 43 functional entities with a single eDNA marker and videos, respectively, and higher functional richness for eDNA than videos. Despite gaps in genetic reference databases, eDNA also detected a higher fish phylogenetic diversity than videos; accumulation curves showed how 1 eDNA transect detected as much phylogenetic diversity as 25 hr of video. Environmental DNA metabarcoding can be used to affordably, efficiently, and accurately census biodiversity factors in marine systems. Although taxonomic assignments are still limited by species coverage in genetic reference databases, use of MOTUs highlights the potential of eDNA metabarcoding once reference databases have expanded.


Uso de ADN Ambiental en la Evaluación de la Diversidad Funcional y Filogenética de los Peces Resumen La evaluación del impacto de los cambios globales y la efectividad de la protección es un paso fundamental para el monitoreo de peces marinos. La mayoría de los métodos tradicionales de censos son demandantes o destructivos, por lo que las estrategias no letales y no intrusivas basadas en videograbaciones y en el ADN ambiental (ADNa) son alternativas a los censos visuales submarinos y a la pesca. Sin embargo, todavía no se conoce la habilidad que tienen estos métodos para detectar diferentes factores de la biodiversidad más allá de la diversidad taxonómica. Para los peces óseos y los elasmobranquios, comparamos el desempeño de la caracterización genética con ADNa y del video remoto de larga duración para evaluar la diversidad funcional y filogenética de las especies. Usamos diez muestras de ADNa tomadas de 30 litros de agua cada una y 25 horas de vídeos submarinos grabados durante cuatro días en la Isla Malpelo (costa del Pacífico de Colombia), un área marina protegida remota. La caracterización genética con el ADNa detectó 66% más unidades taxonómicas moleculares operacionales (UTMOs) que el video. Encontramos 66 y 43 entidades funcionales con un solo marcador de ADNa y con el video, respectivamente, y una riqueza funcional más alta para el ADNa que el video. A pesar de los vacíos en las bases de datos genéticos usadas como referencia, el ADNa también detectó una diversidad filogenética más alta que aquella en los videos; las curvas de acumulación mostraron cómo un solo transecto de ADNa detectó tanta diversidad filogenética como 25 horas de video. La caracterización genética con ADN ambiental puede usarse para censar los factores de biodiversidad de manera asequible, eficiente y certera en los sistemas marinos. Aunque las atribuciones taxonómicas todavía están limitadas por la cobertura de especies en las bases de datos genéticos de referencia, el uso de los UTMOs resalta el potencial que tiene la caracterización genética con ADNa una vez que las bases de datos de referencia sean expandidas.


Assuntos
DNA Ambiental , Animais , Biodiversidade , Conservação dos Recursos Naturais , Código de Barras de DNA Taxonômico , Monitoramento Ambiental , Peixes/genética , Caça , Filogenia
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