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Acute toxicity of mercury to freshwater cultured milkfish Chanos chanos: Clinical symptoms and lethal concentration assessment
No full textThe increasing use of mercury in the industrial sector poses significant risks to freshwater ecosystems and aquatic organisms. Milkfish (Chanos chanos), a widely consumed species, is now being reared in freshwater environments, raising concerns about mercury bioaccumulation and food safety. This study aimed to determine the median lethal mercury concentration for milkfish at 96 hours (LC50) in freshwater using an experimental approach and probit analysis. Five mercury concentrations were tested: 0 (control), 0 .110 mg Hg/L, 0.195 mg Hg/L, 0.347 mg Hg/L, and 0.618 mg Hg/L. The results indicated that mercury is highly toxic to milkfish, with a 96-hour LC50 of 0.147 mg Hg/L. Clinical symptoms observed included loss of reflex movements, irregular swimming, frequent surfacing with widened mouth and operculum openings, convulsions, and ventilation of the ram before mortality. These findings highlight the acute toxicity of mercury in freshwater milkfish and underscore the potential health risks associated with mercury contamination in aquaculture systems.PublishedReferee
Ocean Decade Vision 2030 White Papers – Challenge 7: Sustainably Expand the Global Ocean Observing System.
No full textThe strategic ambition is to develop an operational, comprehensive, and resourced system that delivers priority observations and information to guide mitigation and adaptation responses to climate change, sustains ocean health within a sustainable blue economy, and facilitates informed decision-making for science, business and society. Such a system is envisioned to be co-designed, fit-for-purpose, multidisciplinary, geographically expanded, responsive, and sustainable in time, delivering ocean observations to all nations and users, prioritising societal needs. Transforming ocean observations into accessible information will require integration across disciplines, across national observing systems, along the value chain, and across stakeholders. Innovative technology approaches and a diversified set of actors and approaches will be required for success. The Global Ocean Observing System (GOOS) of IOC UNESCO can provide the implementation framework for Challenge 7 and the UN Ocean Decade provides the opportunity and vehicle for transformation. Five recommendations have been identified to fulfil the strategic ambition of Ocean Decade Challenge 7. Act now on known observational needs. Upgrade and expand ocean observing capacity in poorly-observed areas such as polar regions, island nations and territories, coastal areas of developing nations, coastal systems that are rapidly changing, and the under-observed deep ocean. Thematic priorities for ocean observing by 2030 should focus on key climate risk and adaptation needs, extreme events, coastal services for ocean management, ocean carbon, marine pollution, biogeochemistry, and biodiversity. Adopt new economic thinking. Establish new and sustained financing mechanisms for global ocean observing, including resourcing for Small Island Developing States (SIDS) and Least Developed Countries (LDCs). Use economic models for ocean investment to diversify and accelerate investment in ocean observing and infrastructure from new actors. Partnerships are key. Increase national, regional and global coordination, focusing on co-design and partnerships. Improved coordination that uses the GOOS framework to ensure standards, best practices for a sustainably expanded GOOS. Diversify partnerships across sectors (economic, public, private, and philanthropic) and embrace the abilities and needs of the different stakeholders to co-design, co-develop, and co-deliver observations that translate into the information required by these sectors. Technology and innovation will be a pillar. Integrate and harmonise observations across observing platforms (in situ, satellite, emerging networks). Develop innovative in situ, autonomous and cost-effective technologies to maximise reach, ensuring standardisation and best practices. Technology barriers still need to be lowered to ensure everyone has equitable access to observing technology and has the ability to use these assets. Artificial Intelligence (AI) and Machine Learning (ML) tools will provide user-ready information from integrated observations to democratise information for users. Expanded, capable, and diversified workforce. Expand and diversify the workforce of skilled and trained ocean professionals. Training and capacity development will be critical across the observing ‘ecosystem’ outlined in the Framework for Ocean Observing (FOO), from data collection to data analysis and modelling, and for data use and application.PublishedReferee
Макрозообентос эстуария малой лососевой реки острова Сахалин на примере р. Горная
No full textEstuaries as a connecting link between freshwater and marine ecosystems play a special role in salmon rivers. The success of adaptation of juvenile salmonids during the transition to the marine period of life depends on the conditions in estuaries. The work continues the previously started series of publications on the rivers of Sakhalin Island. Using the example of one of the small watercourses in the southeastern part of the island, the hydrological parameters and the structural organization of benthos communities in the atypical estuary have been considered. In the absence of storm surges, penetration of sea water into the water body does not occur; at high tide, water with a salinity of more than 12 psu is observed only at the mouth at the bottom; at low tide, the estuary is completely filled with water with a salinity of 0.1 psu and lower. Studies of the hydrological regime and composition of the bottom fauna were carried out in July 2022. Zoobenthos samples were taken along the longitudinal profile of the estuary at five sections (75 samples in total). Most of the estuarine reach is inhabited by species characteristic of the lower parts of the island watercourses. High environmental variability determines the formation in the estuary of young and unstable benthos communities represented by rapidly reproducing small-sized species.Эстуарии как связующее звено между пресноводными и морскими экосистемами в лососевых реках играют особую роль. От условий в эстуарных зонах рек зависит успех адаптации молоди лососевых рыб при переходе к морскому периоду жизни. Работа продолжает начатый ранее цикл публикаций по рекам о-ва Сахалин. На примере одного из малых водотоков юго-восточной части острова рассматриваются гидрологические параметры и особенности структурной организации сообществ макрозообентоса эстуария, не типичного по своим характеристикам. В отсутствии штормовых заплесков проникновения морских вод в эстуарий практически не происходит. Воды с соленостью более 12 psu отмечаются только в устье у дна во время прилива, в отлив эстуарий полностью заполняется водой с соленостью 0,1 psu и ниже. Исследования гидрологического режима и донной фауны были проведены в июле 2022 г. Пробы зообентоса отбирали по продольному профилю эстуария на пяти разрезах (суммарно 75 проб). Работы показали, что большую часть эстуария заселяют виды, характерные для нижней ритрали водотоков острова. Высокая изменчивость среды обусловливает формирование в этом эстуарии молодых и нестабильных сообществ макрозообентоса, представленных быстроразмножающимися мелкоразмерными видами.PublishedReferee
Variación de la distribución de centolla (Lithodes santolla) en la Patagonia sur argentina y su relación con la temperatura del mar
No full textLithodes santolla (Molina, 1785) es un crustáceo decápodo conocido vulgarmente como centolla o “southern king crab”. Se distribuye en aguas templado-frías del cono sur americano, en el océano Atlántico y Pacífico. Es una especie bentónica que puede habitar un rango de profundidad desde la costa hasta más allá de los 700 m de profundidad. Debido a las altas concentraciones y al valor comercial que tienen las centollas se las ha considerado un recurso con un particular interés en la investigación. Actualmente en Argentina se han definido cuatro efectivos de pesca: el Efectivo de la Plataforma y Talud Bonaerense (EPTB), el Efectivo del Sector Patagónico Central (ESPC), el Efectivo del Sector Patagónico Sur (ESPS) ubicado en la costa atlántica de la provincia de Santa Cruz y Tierra del Fuego y el Efectivo del Canal Beagle (ECB). En los efectivos ESPC y ESPS la pesca industrial se realiza con buques congeladores desde el año 2008 y 2016, respectivamente. La temperatura del agua de mar puede ser una limitante en la distribución de especies ectotérmicas, ya que afecta procesos fisiológicos, reproductivos y comportamentales. Además, conocer las relaciones entre las variables ambientales y los procesos biológicos de la especie permiten una mejor gestión y evaluación de la pesquería. En Argentina no se cuenta con trabajos científicos donde se relacionen las abundancias de L. santolla con la temperatura ambiental. El objetivo principal de este estudio fue analizar la variación interanual de abundancias de centolla en relación con la temperatura del fondo del mar, particularmente en el Sector Patagónico Sur.BachelorsTesis (licenciatura
The position and importance of Sinop in the Black Sea fisheries
No full textLocated in the northernmost part of Türkiye and situated on the Boztepe Peninsula, Sinop has a surface area of 5.791 km2. Sinop is one of the smallest provinces of Türkiye and covers approximately 0.8 percent of Türkiye's surface area. Sinop Province is one of the regions with the highest fish outflow in the southern Black Sea coast of Türkiye where the most intensive fishing is carried out. There are many fish meal-oil factories, aquaculture processing and utilisation facilities and cold storages in Sinop due to intensive fishing and production. Due to the potential of Sinop's fisheries, the biggest export income is also provided from here. There are also dam lakes with large water surface area in Sinop Province. An intensive amount of aquaculture is carried out from these dam lakes. In addition, Sinop coasts are seen as the most suitable conditions in the Black Sea Region as a new and strong alternative attraction centre for aquaculture facilities. Especially after 2018, serious aquaculture activities are carried out on the east coast of Sinop and there are many project applications for new potential areas on the west coast of Sinop. Anchovy, Atlantic bonito, horse mackerel, whiting, bluefish, flathead grey mullet, red mullet, shad, garfish, and turbot are among the most fished economic species on the coasts of Sinop. In the inland waters of Sinop, the most caught fish species are carp and pike. The only species produced in the inland waters of Sinop is rainbow trout. The production of trout as trade name Turkish Salmon started in 2018 on the coasts of Sinop and continues and peaked in 2022 with 17,332,975 kg. Exported to 48 countries, Turkish Salmon was 45,548,737 kg in January-November 2022 and this rate increased to 57,211,587 kg with a 26% change in January-November 2023. Sea bass was only farmed in cages on the coasts of Sinop in 2019 and 2020. Except for 2021, veined Rapa whelk have been caught from the coasts of Sinop for the last 10 years. Veined Rapa whelk meat is exported to USA, Korea, China, Japan, Taiwan, and Singapore. Operculum of veined Rapa whelk is exported to S. Arabia and Libya countries. Sand mussel from the Sinop coasts was caught only in 2022. With the newly planned marine aquaculture capacities on the coasts of Sinop, its contribution to Turkish aquaculture production continues to increase. This table shows that Sinop is one of the leading provinces of Türkiye in terms of aquaculture processing facilities.PublishedReferee
Greater flamingos as winged flagship species at the boundaries of Circeo Man and Biosphere Reserve
No full textThe greater flamingo (Phoenicopterus roseus, Pallas 1811) is a typical migratory Mediterranean species, even if considered nesting in the area only from few years to date, with a first documentation of a nesting event in Italy in 1993 (Schenk et al., 1995; Béchet et al., 2009). The typical coloring pattern due to the feeding strategy adopted by these migrating birds make the species particularly interesting from the wider audience. It is what was observed in the nearby of the transitional ecosystems associated to the brackish water of Caprolace Lake. This place is not so crowded normally, but due to the presence of many photographers and curious observers the presence of the pinkish colony turned rapidly the lake shores into a meeting point for many curious eyes attracted from this natural astonishing event. On 2nd February is normally celebrated the World Wetland Day and this contribution is published accordingly, in order to celebrate somehow these field observations occurred in the nearby of this important date, considered as the anniversary of the adoption of the Convention on Wetlands of International Importance, signed in Ramsar on 2 February 1971.PublishedReferee
Aquaculture nursery systems after infection with Vibrio harveyi
No full textPresent study evaluated the survival, post-larvae quality, and the population of Penaeus monodon (Black tiger shrimp) and Oreochromis niloticus (Tilapia), after the addition of two strains of bacteria i.e Lactobacillus sp. and Bacillus sp. The Vibrio harveyi were isolated and identified from hatchery-reared larvae, at Biotechnology Research Department Ministry of Education, Republic of Union of Myanmar. Preliminary screening for antimicrobial activity of six Lactobacillus sp. and six Bacillus sp. Incubated and tested with V. harveyi using agar, well diffusion assay and tube screening methods. Inhibition activity results were the best at 3 days incubation for Lactobacillus sp. and the optimal result for inhibition activity for Bacillus megaterium at 5 days, with lactose sugar on V. harveyi. Before in vivo test, in vitro inhibition test of V. harveyi competition with probiotic of different concentrations of 10 ml/ton, 20 ml/ton, 30 ml/ton and 40 ml/ton. The results in all probiotic treatments were almost similar. Inhibitory affects were found in tube screening method, where, V. harveyi level reduced to 10 3 CFU/ml from 10 7 CFU/mlin 4 days. The pathogenicity test was conducted for a period of 2 days with Penaeus monodon (Black tiger shrimp) at post larval stages and Oreochromis niloticus (Tilapia) at fingerling stages, where they were exposed for 106, 107 and 108 CFU/ml of V. harveyi resulted 100% mortality. The probiotic treatment exhibited 50%, 70% and 80% survival rate of the fish infected with 106, 107 and 108 CFU/ml, respectively. It was detected the lower load of Vibrio ssp. bacteria with potential of pathogenicity after feeding with six Lactobacillus sp. and six Bacillus sp.PublishedReferee
Ocean Decade Vision 2030 White Papers – Challenge 5: Unlock Ocean-Based Solutions to Climate Change.
No full textBy 2030, success for Ocean Decade Challenge number 5 will be marked by a move toward a more sustainable and climate-resilient ocean that aligns with the United Nations’ sustainable development goals. Crucially, the success of Challenge 5 is intricately linked to the outcomes of Challenges 1 to 4, which focus on understanding climate-ocean interactions, controlling marine pollution, conserving biodiversity, and ensuring sustainable food production. Success will include fulfillment of critical science and knowledge gaps with respect to climate adaptation and mitigation. Both approaches need to be addressed in parallel. Key mitigation approaches include the development of marine renewable energies, reduction in marine pollution, the development of blue carbon ecosystems, and marine carbon dioxide removal (mCDR). Adaptation approaches include increased ocean literacy/awareness; co-designed governance and co-operation; improved risk reduction policies; and improved predictive capability of ocean, climate, and weather forecasts. Challenge 5 was reported as one of the most commonly cited Challenges for knowledge uptake in the Decade. However, important gaps still remain in terms of the geographical scope of the actions under this and other challenges.PublishedReferee
Opportunities and risks of the blue economy for innovative companies in the sustainable aquaculture sector
No full textThe oceans play a crucial role in the global ecosystem and offer solutions to meet the growing demand for food, water, and energy. However, a new economic concept is needed to regulate and sustainably exploit the maritime resources offered by the marine ecosystem to ensure sustainable development. It is in this initiative that the concept of the blue economy has emerged, in response to the inadequacy of measures taken by States to meet their obligations and achieve their objectives in terms of marine biodiversity conservation. This is how the blue economy concept was born, in response to the inadequacy of state measures to conserve marine biodiversity. This concept proposes an innovative solution integrating aquatic and human resources into sustainable economic activities. The aim of this study is to understand the opportunities and threats that the blue economy represents for innovative companies. This short literature review, based on a SWOT (Strengths, Weaknesses, Opportunities, and Threats) diagnosis of innovative companies, identified a number of obstacles to the development of the blue economy, such as climate change, lack of financing and the lack of instruments for measuring the performance of the blue economy. Action strategies could be implemented to mitigate risks, threats and hazards, and consider an economic approach that reconciles marine and terrestrial ecosystems.PublishedReferee
Length-weight relationship of selected catfish species from the stretch between downstream Lloyds Barrage and upstream Kotri Barrage, Indus River, Sindh, Pakistan
No full textCatfishes are the crucial group in order Siluriformes occupy upper trophic levels due to their predatory feeding habits. This study examines the length-weight relationships of selected catfish species including Bagarius bagarius, Ompok bimaculatus, Heteropneustes fossilis, and Clupisoma garua collected from downstream Lloyds Barrage to upstream GM Barrage (Kotri Barrage) in the Indus River, Sindh, Pakistan. Fish samples were obtained over a year (July 2017 - June 2018) with the help of local fishermen and analyzed at the University of Sindh, Jamshoro. Measurements were taken using a digital balance, and regression analysis was performed using the cube law formula. The study found the regression parameters b and R² for B. bagarius (2.71 and 0.98), O. bimaculatus (2.82 and 0.94), H. fossilis (2.95 and 0.98), and C. garua (3.016 and 0.99). The "b" values suggested isometric growth for C. garua, while the other species indicated negative allometric growth. These values fall within the range (2.5-3.5), supporting the suitable growth of H. fossilis in the Indus River. This research provides vital baseline data for fisheries scientists, enhancing future studies and management strategies for these catfish species.PublishedReferee