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Population dynamic and biological characteristics of Longnose trevally Carangoides chrysophorys in the Persian Gulf & Oman Sea (Hormozgan Province)
No full textThe long nose trevally, Carangoides chrysophrys is one of important commercial species of family carangidae in the Persian Gulf and Oman Sea .population dynamic parameters, reproductive biology and feeding habits of this species were studied from April 2016 to march 2017 in the Coastal Waters of Hormuzgan province. Length frequency analysis of 440 specimens of C.chrysophrys with total length (TL) ranged from 250 to 800 mm were shown isometric growth. Growth parameters including K, L and t0 were calculated 0.390 (1/year), 66.86 Cm and 0.029 Year respectively. The instantaneous rate of total mortality (Z), natural mortality (M) and fishing mortality (F) were estimated 1.21, 0.761 and 0.449 (1/year) respectively. Exploitation rate was 0.4 per year indicated that fishing effort on this species is in a moderate condition. Reproductive studies showed that C.chrysophrys has long spawning period with two peaks in spring and autumn respectively. Females reached 50% sexual maturity at 38.4 cm. Stomach content analysis of this species revealed that bony fishes (% 77) formed main food and followed by crustacean (% 18) and molluscs (% 5) as random food.Ph
COESS: Seafloor seeps in Japan Sea. [Full Depth drone video]
No full textSeafloor journey around methane seepsPublishe
Ocean Decade Vision 2030 White Papers – Challenge 6: Increase Community Resilience to Ocean Hazards.
No full textBy 2030, successful achievement of Ocean Decade Challenge No. 6 will require demonstrating substantial advancements within the global community towards enhancing their resilience to coastal and ocean hazards. This includes implementing two crucial elements: (1) establishing comprehensive 'people-centered' early warning systems capable of addressing multiple hazards, and (2) devising adaptation strategies that specifically target risks associated with the ocean, including those linked to climate change. These endeavours will play a pivotal role in guiding sustainable practices in ocean planning. Success will also hinge on addressing critical gaps in scientific understanding and knowledge across important components such as risk assessment and risk reduction, in addition to putting in place robust institutional mechanisms for implanting novel solutions that contribute to coastal resilience. Some key elements to be addressed in this context include: (i) gathering and generating observational and modelling datasets relevant to risk assessment, including downscaled climate scenarios for coastal regions, within robust data-sharing frameworks; (ii) promoting interdisciplinary and international research and innovation to tackle challenges comprehensively, with a focus on methodologies like Digital Twin approaches; (iii) improving standards for risk communication at both national and international levels; (iv) fostering partnerships at various scales involving local communities, public and private disaster risk reduction entities, governmental bodies, and academic institutions; (v) building capacity in research and communication to cultivate a shared understanding of coastal resilience strategies; and (vi) enhancing resilient infrastructure and promoting sustainable resource management along coastlines. It is imperative to establish partnerships with existing international UN programs dedicated to disaster risk reduction and coastal resilience. Strengthening connections with UN Decade Actions through Decade Coordination Offices and Decade Collaboration Centers is of utmost importance for effective coordination and collaboration. Based on the above strategic ambition it is also suggested that the formulation of the Ocean Decade Challenge could be modified as follows: Increase community resilience to ocean and coastal risksPublishedReferee
Coral health and its research in the Caribbean and Cuba.
No full textLa salud de los corales es un tema de gran importancia en el Caribe y en Cuba, ya que estos ecosistemas marinos son vitales para la biodiversidad y la economía de la región. Los arrecifes de coral albergan una gran variedad de especies. Sin embargo, constituyen un ecosistema bajo amenaza debido a la combinación de diferentes factores, como el cambio climático, la contaminación, la sobrepesca y la acidificación del océano. El Caribe es considerado un “punto caliente” para las enfermedades, debido a la rápida aparición y virulencia de nuevos síndromes en la región en las últimas décadas. Cuba no se encuentra exenta de este panorama. Aun así, los estudios realizados han demostrado que los porcentajes de afectación por enfermedades son bajos y el número de enfermedades reportado para sus arrecifes también es bajo, en comparación a lo reportado para otros sitios del Caribe. Es por lo que este trabajo tiene como objetivo recopilar información actualizada sobre el estado de salud de los corales en el Caribe y en Cuba. La sistematicidad y la constancia en el monitoreo de los arrecifes constituye una urgencia en aras de conocer el estado de salud en que se encuentran, manejarlos de manera sostenible y así evitar daños irreparables que conlleven a su pérdida definitiva. Planes de conservación que combinen un manejo efectivo con iniciativas de ciencia ciudadana han demostrado ser sostenibles y beneficiosos, tanto para los arrecifes como para la sociedad.The health of corals is a topic of great importance in the Caribbean and in Cuba since these marine ecosystems are vital for biodiversity and the economy of the region. Coral reefs house a wide variety of species. However, they constitute an ecosystem under threat due to the combination of different factors, such as climate change, pollution, overfishing and ocean acidification. The Caribbean is considered a "hotspot" for diseases, due to the rapid appearance and virulence of new syndromes in the region in recent decades. Cuba is not exempt from this panorama, even so, studies have shown that the percentages of disease affectation are low, and the number of diseases reported for its reefs is also low compared to what is reported for other Caribbean sites. This is why this work aims to collect updated information on the health status of the corals in the Caribbean and in Cuba. The systematicity and constancy in the monitoring of the reefs constitutes an urgency to know the state of health in which they are, manage them sustainably and thus avoid irreparable damage that leads to their definitive loss. Conservation plans that combine effective management with citizen science initiatives, have proven to be sustainable and beneficial for both reefs and society.PublishedReferee
Resistance profiling, evolution of biofilm formation and genetic diversity of Vibrio alginolyticus isolated from aquaculture systems
No full textThis study analyzes 26 presumptive Vibrio alginolyticus strains extracted from two fish farms (Khenis and Hergla, East Tunisia) that raised sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax). In addition, from a shellfish farm located in Menzel Jmil, North Tunisia that raises mussels (Mytilus edulis) and oysters (Crassostrea gigas). We have evaluated (i) the discriminatory power of PCR-RFLP for identification of closely related strains, (ii) the antibiotic resistance of the V. alginolyticus strains and (iii) their ability to form a biofilm in aquaculture farm. Results showed that there is great heterogeneity in the diversity observed via the PCR-RFLP method related to the number of 20 genotypes generated by the two enzymes SduI and FaqI tested. The heterogeneity was observed in both fish (aquaculture farm) and bivalve (shellfish farm) origins, as well as in the same sample. For antibiotic resistance, all isolates present a high resistance to ampicillin, erythromycin, cefotaxime, kanamycin and doxycycline. The resistance is displayed by 15 distinct profiles. The Multiple Antibiotic resistance (MAR) index was ranged from 0.55 to 0.80 for the isolates from the aquaculture farm of Hergla followed by the index aquaculture farm of Khenis (0.55 to 0.75). While for the shellfish farm of Menzel Jmil the index ranges from 0.50 to 0.65. This finding indicated high-risk sources of antibiotic contamination in the three locations. Isolates from aquaculture systems with strong biofilm formation have been found to be resistant to antibiotics, which may allow them to survive longer in these environments. Present findings could be relevant in aquaculture systems and underscore the importance of the linkage between adhesion, antibiotic susceptibility, and genetic diversity of these pathogenic bacteria to avoid fish and shellfish diseases. The results will provide helpful guidance on how to use antibiotics to control Vibrio alginolyticus diseases in aquaculture to be healthy.PublishedReferee
Ocean Decade Vision 2030 White Papers – Challenge 3: Ocean Contributions to Nourishing the World’s Population.
No full textThis draft White Paper has been prepared as part of the Vision 2030 process of the United Nations (UN) Decade of Ocean Science for Sustainable Development (hereafter, Ocean Decade). The Vision 2030 process aims to identify tangible measures of success for each of the ten Ocean Decade Challenges by 2030. From a starting point of existing initiatives underway in the Ocean Decade and beyond, and through a lens of priority user needs, the process determines critical gaps in science and knowledge, needs for capacity development, priority datasets, infrastructure, and technology for each Challenge. Focusing investments in science and knowledge to address these needs will help ensure progress towards meeting each critical Challenge by the end of the Ocean Decade in 2030. The results of the process will contribute to the scoping of future Decade Actions, identification of resource mobilisation priorities, and ensure relevance of the Challenges over time. This draft White Paper is one of a series of ten White Papers, all of which have been authored by an expert Working Group and discussed at the 2024 Ocean Decade Conference. A synthesis report, authored by the Intergovernmental Oceanographic Commission of the United Nations Educational, Scientific, and Cultural Organization (UNESCO/IOC), will accompany the White Papers. With a substantial portion of people depending on the ocean as a primary source of nutrition and livelihood, a significant challenge comes into focus: How can we ensure that the ocean's resources continue to effectively nourish an expanding global population? The Ocean Decade responds to this critical concern through its Challenge 3: “Sustainably nourish the global population”.PublishedReferee
Uso e cobertura da terra determinam a diversidade taxonômica e funcional de insetos aquáticos em riachos tropicais.
No full textStreams are ecosystems closely dependent to their adjacent ecotones, representing important water recharge sources for drainage networks and playing a central role in global nutrient cycling. The primary source of energy in streams comes from allochthonous material originating from riparian vegetation, which becomes available through processing performed by aquatic organisms. Modifications in the composition of the adjacent vegetation, which can be natural or due to land use and occupation, may alter the ecosystem functioning. Despite their critical role in preserving biodiversity, riparian ecosystems face continuous alteration or even removal. Anthropogenic activities, such as excessive use of pesticides and fertilizers in rural areas, and catchment imperviousness in urban areas, for example, negatively affect water quality, leading to contamination and disruptions in the food chain. Studies predominantly focus on densely forested riparian zones, composed mainly of trees, but natural riparian zones with herbaceous or shrubby vegetation have effects less explored when compared to woody vegetation. These include differences in channel stability and morphology, because woody vegetation is more suitable for stabilization of stream banks than herbaceous vegetation. These differences are particularly relevant for organisms like aquatic insects, that play a fundamental role in energy transfer to higher trophic levels and are widely used as bioindicators, given their sensitivity to environmental changes. Metrics such as richness and abundance are commonly used to estimate levels of biodiversity, but for a comprehensive understanding of the role of such species in ecosystem functioning, it is essential to also consider functional diversity. In this context, the following aspects were assessed: i) the effect of sub-basin riparian vegetation stratum (tree x shrub) on the composition and beta-diversity of aquatic insects in tropical streams and ii) the relationship between different levels of anthropogenic intensification and taxonomic and functional indices of aquatic insects, as well as their relationship with environmental variables. The study concluded that functional diversity was more sensitive than taxonomic diversity to changes related to land use and cover in riparian vegetation. Vegetation stratum (tree and shrub) significantly altered total functional diversity, while anthropogenic intensification significantly reduced all functional indices analysed and only one taxonomic index. The results obtained and analysed contributed to an analytical understanding of the functioning of tropical aquatic ecosystems. Furthermore, the study provides valuable parameters and insights for future predictions and mitigation strategies in environments affected by human activities.Riachos são ecossistemas estritamente dependentes dos seus ecótonos adjacentes, representando importantes fontes de recarga de água para redes de drenagem e desempenhando um papel central no ciclo global de nutrientes. A principal fonte de energia dos riachos é proveniente do material alóctone da vegetação ripária, que se torna disponível através do processamento pelos organismos aquáticos. Modificações na composição da vegetação adjacente, que podem ser naturais ou decorrentes do uso e cobertura da terra, podem alterar as funções ecossistêmicas. Apesar do seu papel fundamental na preservação da biodiversidade, os riachos são continuamente alterados ou até mesmo removidos. As atividades antrópicas, como o uso excessivo de pesticidas e fertilizantes nas zonas rurais, e a impermeabilização do solo em áreas urbanas, por exemplo, possuem um impacto negativo na qualidade da água, levando à contaminação e a perturbações na cadeia alimentar. Os estudos são predominantemente realizados nas zonas ripárias altamente florestadas, compostas principalmente por árvores de grande porte, mas as zonas ripárias naturais com vegetação herbácea ou arbustiva têm efeitos menos explorados quando comparadas com a vegetação arbórea. Entre os efeitos, incluem diferenças na estabilidade e morfologia do canal, porque a vegetação arbórea é mais adequada para a estabilização das margens do que a vegetação herbácea. Estas diferenças são particularmente relevantes para organismos como os insetos aquáticos, que desempenham um papel fundamental na transferência de energia para níveis tróficos superiores e são amplamente utilizados como bioindicadores, dada a sua sensibilidade às alterações ambientais. Métricas como riqueza e abundância são comumente utilizadas para estimar níveis de biodiversidade, mas para uma compreensão abrangente do papel dessas espécies no funcionamento do ecossistema, é essencial considerar também a diversidade funcional. Neste contexto, avaliou-se os seguintes aspectos: i) o efeito do estrato de vegetação ripária (arbóreo x arbustivo) da sub-bacia sobre a composição e diversidade beta de insetos aquáticos em riachos tropicais e ii) a relação entre a intensificação antrópica e as variáveis ambientais com índices taxonômicos e funcionais de insetos aquáticos. O estudo constatou que a diversidade funcional foi mais sensível às mudanças relacionadas com o uso e cobertura da terra na vegetação ripária. O estrato da vegetação (arbóreo e arbustivo) alterou significativamente a diversidade funcional total, enquanto a intensificação antrópica reduziu significativamente todos os índices funcionais analisados e apenas um taxonômico. Os resultados obtidos e analisados contribuíram para uma compreensão analítica do funcionamento dos ecossistemas aquáticos tropicais, destacando os efeitos do uso e cobertura da terra na diversidade funcional dos insetos aquáticos, em dois hotspots da biodiversidade. Outrossim, o estudo indica parâmetros e informações valiosas para futuras previsões e estratégias de mitigação em ambientes afetados por atividades humanas.Ph
Nuevos registros del cangrejo marino invasor Charybdis hellerii (Crustacea, Brachyura) en Cuba
No full textThe brachyuran crab Charybdis hellerii is originally from the Pacific; nevertheless, the spe- cies has been introduced to tropical waters globally. Its initial sighting in the Western Atlan- tic was documented in 1990 based on specimens collected in Cuba in 1987. In this paper, we present findings of C. hellerii from two localities in eastern Cuba: Santiago de Cuba and Taco bays. Up to this point, the species has solely been documented in estuaries in Cuba, and it likely exists throughout the entire archipelago. Given its feeding behaviour and extensive distribution, encompassing areas within the National Park Alejandro de Humboldt, this species can be key in the formulation of conservation plans for Cuban marine ecosystems.El cangrejo braquiuro Charybdis hellerii es originario del Pacífico; sin embargo, la espe- cie ha sido introducida en aguas tropicales a nivel mundial. Su primera aparición en el Atlántico Occidental se registró en 1990 en base a especímenes recolectados en Cuba en 1987. En este artículo, presentamos los hallazgos de C. hellerii en dos localidades en Cuba oriental: las bahías de Santiago de Cuba y Taco. Hasta el momento, la especie solo ha sido registrada en estuarios en Cuba y es probable que esté presente en todo el archipiélago. Dada su conducta alimentaria y su amplia distribución, que incluye áreas dentro del Par- que Nacional Alejandro de Humboldt, esta especie puede ser clave en la formulación de planes de conservación para los ecosistemas marinos cubanos.PublishedReferee