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Assessment to modify the minimum legal size of capture of the lobster Panulirus argus in Cuba.
No full textLa talla mínima legal de captura (TMLC) en la pesquería de langosta en Cuba es de 76 mm de largo del cefalotórax (LC) y data de 2007. Mediante métodos basados en la estructura de tallas de las capturas, se evaluó que con una TMLC de 82 mm LC en todas las regiones de pesca, se esperan incrementos a nivel nacional alrededor de 3, 9 y 11 % de captura, biomasa y potencial reproductor respectivamente, en relación con los valores promedio de estas variables durante el período 2017- 2021. La disminución inmediata de la captura por aumentar la TMLC en 6 mm (de 76-82 mm LC), se debe recuperar dentro de la misma temporada de pesca, ya que el crecimiento por muda es de más de 6 mm LC y esta se produce con una frecuencia entre 3 y 4 veces durante el año. Se recomienda Incrementar la talla mínima legal de captura en la pesquería de langosta en Cuba a 82 mm LC, la cual estará más acorde con la talla de primera madurez sexual, estimada alrededor de 95 mm LC para hembras en la región suroccidental.The minimum legal size of capture (MLSC) in the fishery for lobster in Cuba is 76 mm of cephalothorax length (CL) and dates from 2007. Using length-based models, it was evaluated that a MLSC of 82 mm CL in all fishing regions, will increase around 3, 9 and 11 % in catch, biomass and reproductive potential respectively, in relation to the average values of these variables during the 2017-2021 period. The immediate decrease in the catch due to increasing the MLSC by 6 mm (from 76 to 82 mm CL), must be recovered within the same fishing season, since the growth increment by molting is more than 6 mm CL and the molt frequency is between 3 and 4 times during the year. It is recommended to increase the minimum legal size of capture in the lobster fishery in Cuba to 82 mm CL, which will be more in line with the size at first maturity, estimated around 95 mm CL for females in the southwestern region.PublishedReferee
Microbiological quality of the queen conch dough (Lobatus gigas) processed by Cuban fishing industries.
No full textEl cobo (Lobatus gigas) es un importante recurso pesquero para Cuba y el Caribe debido a su relevancia económica. El presente trabajo tuvo como objetivo evaluar la calidad microbiológica de la masa de cobo procesada por industrias pesqueras cubanas durante el período 2017-2019. Para ello se determinaron por cada año los microorganismos indicadores: microorganismos a 30 °C (NC ISO 4833-1: 2014), E. coli (NC ISO 7251: 2011) y microorganismos patógenos: Vibrio cholerae y Vibrio parahaemolyticus (UNE-EN ISO 21872: 2018) y Salmonella spp. (NC ISO 6579-1: 2019). Los resultados se compararon con los criterios microbiológicos establecidos en la NC 585: 2017. En los años 2017, 2018 y 2019 se analizaron 40, 35 y 45 muestras respectivamente. Durante el período analizado el indicador con mayores resultados no conformes de acuerdo con la norma cubana NC 585: 2017 fue el de microorganismos a 30 °C. Los conteos de E. coli estuvieron dentro de los límites establecidos por la Norma. Las muestras analizadas en los tres años dieron ausencia de microorganismos patógenos.The queen conch (Lobatus gigas) is an important fishery resource for Cuba and the Caribbean due to its economic relevance. The objective of this work was to evaluate the microbiological quality of the queen conch processed by Cuban fishing industries during the 2017-2019 period. For this, the indicator microorganisms were determined for each year: microorganisms at 30 ºC (NC ISO 4833-1: 2014), E. coli (NC ISO 7251: 2011) and pathogenic microorganisms: Vibrio cholerae y Vibrio parahaemolyticus (UNE-EN ISO 21872: 2018) and Salmonella spp. (NC ISO 6579-1: 2019). The results were compared with the microbiological criteria established in NC 585: 2017. In the years 2017, 2018 and 2019, 40, 35 and 45 samples were analyzed, respectively. During the analyzed period, the indicator with the highest non-compliant results according to the Cuban standard NC 585: 2017 was that of microorganisms at 30 ºC. The E. coli counts were within the limits established by the Standard. The samples analysed in the three years gave absence of pathogenic microorganisms.PublishedReferee
Состояние сырьевой базы и среды обитания раков в бассейне р. Сал
No full textCrayfish is a well-established fishing target in the basin of the Sal River within the Rostov Region. The climate change causing unstable hydrological conditions, as well as the extensive anthropogenic activity have a significant impact on aquatic biological resources. This work was aimed at the investigation of the status of the water bodies and exploitable biological resources (crayfish) in the water bodies of the Sal River Basin, with the anthropogenic pressure and climate changes taken into account. A retrospective analysis of the following parameters has been carried out: hydrological regime of the Sal River Basin since 1937, of the habitat conditions and status of the crayfish population (2012–2021), and the status of its feeding resources (2000–2013) in the context of anthropogenic activities and climate change. It has been found out that the hydrological regime of the water-deficient basin of the Sal River since the mid-1970s has been characterized by a decreased runoff during the spring flood and an increased runoff during the winter and summer–autumn low water period due to air temperature increase in the cold season. Due to the decrease in the water content of the Sal River Basin, the stream water supply lessened and the content of sulfates, chlorides and total dissolved solids in water increased, which resulted in the change of the water type from the hydrocarbonate to the sulfate one. These changes in the concentrations and ratios of salt-forming ions have been also caused by decreased precipitation and an increased feed of ground- and underground waters to the rivers of this basin. The priority toxicants and active ingredients of the pesticides of modern classes found in the water and bottom sediments of the Sal River did not affect the growth and reproduction of the crayfish. Commercial productivity of crayfish stock has shown a trend toward decrease, which resulted from the changes in some observed climate parameters (an increase in air temperature, a decrease in water content in the Sal River Basin), as well as from the increase in total dissolved solids in the water. However, the hydrochemical regime remains to be relatively favorable for life sustenance of the bottom species of aquatic animals, and the anthropogenic pollution of the ecosystem with priority toxicants is low, which makes it possible for the population to maintain stable length composition and similar quantitative values for different length classes of crayfish, as well as its reproduction capacity.Раки являются традиционным объектом промысла в бассейне р. Сал в границах Ростовской области. Климатические изменения, обуславливающие нестабильные гидрологические условия, и активная хозяйственная деятельность оказывают существенное влияние на водные биоресурсы. Целью работы стало изучение состояния водных объектов и промысловых биоресурсов (раки) в водоемах бассейна р. Сал с учетом антропогенного воздействия и климатических изменений. Проведен ретроспективный анализ гидрологического режима бассейна р. Сал с 1937 г., условий среды обитания и состояния популяции раков (2012–2021 гг.), а также их кормовой базы (2000–2013 гг.) под влиянием антропогенного воздействия и климатических изменений. Установлено, что гидрологический режим вододефицитного бассейна р. Сал с середины 1970-х гг. характеризуется снижением стока весеннего половодья и увеличением стока зимней и летне-осенней межени в связи с повышением температуры воздуха в холодный период года. Вследствие снижения водности бассейна р. Сал уменьшились русловые запасы водотоков, увеличилось содержание в воде сульфатов и хлоридов и повысилась общая минерализация воды со сменой типа вод с гидрокарбонатного на сульфатный. Данные изменения концентраций и соотношения солеобразующих ионов обусловлены также снижением атмосферных осадков и увеличением роли грунтовых и подземных вод в питании рек данного бассейна. Концентрации приоритетных токсикантов и действующих веществ пестицидов современных классов в воде и донных отложениях в устье р. Сал не оказывали негативного влияния на рост и размножение раков. Отмечена тенденция снижения промысловой ракопродуктивности популяции раков в результате изменения ряда наблюдаемых климатических параметров (рост температуры воздуха, снижение водности в бассейне р. Сал) и роста минерализации воды. Однако сохранение относительно благоприятного для жизнедеятельности придонных видов водных биологических ресурсов гидрохимического режима и низкого уровня антропогенного загрязнения экосистемы приоритетными токсикантами позволяет популяции сохранять стабильную размерную структуру и близкие количественные показатели размерных групп раков и плодовитости.PublishedReferee
Least-Squares Reverse Time Migration in Pseudodepth Domain and Its Application
No full textThe Cartesian-based least squares reverse time migration (LSRTM) aims to obtain a relatively high-resolution amplitude preserving imaging by calculating and solving the Hessian matrix. In addition, conjugate gradient algorithm is proved to be an efficient iterative method, which makes the traditional LSRTM feasible in practical data processing applications. Each iteration process of LSRTM includes two main parts; The first part is the forward simulation of wavefield, and the second part is the back propagation of wavefield. However, the calculation of these two parts takes a lot of time, and oversampling effects will occur in the calculation process. The thesis develops a smooth understanding of the LSRTM scheme in pseudodepth domain and gives information about this type of wavefield extrapolation method to achieve amplitude-preserved image with low computational costs in terms of memory and time. The underground media faced by seismic exploration usually include low velocity bodies, high steep structures and pore fracture units. When simulating the seismic wavefield in these media, in order to ensure the simulation accuracy and computational stability by finite difference methods, the grid spacing needs to be very small, which leads to the oversampling problem of the traditional finite difference forward simulation method in Cartesian coordinate system. In order to overcome this problem, the pseudo depth domain algorithm is applied to the least-squares reverse time migration to improve its computational efficiency. The problem of stabilizing this Pseudodepth wavefield arises from the introduction of the mapping function and velocity and also the vertical axis operator that converts the finite difference solution partially from time into frequency domains. Stability and convergence analysis suggests that the spatial derivatives of Riemannian axis should be approximated by a mixed Fourier pseudo-spectral and ordinary finite-difference schemes methods using a special Gaussian-like impulse function to generate the vector-matrix of the complex source term within the finite-difference operator, in addition to the mapping velocity, which is a differential form of the initial input velocity model, manifestly controls the CFL conditions of the associated Riemannian-finite difference operator. Numerical and synthetic examples indicated that this approach is more stable and efficient in extrapolating a smooth Riemannian wavefield while maintaining Claerbout’s principle for locating subsurface reflectors also choosing an appropriate sampling rate for the new vertical axis is related inversely by the maximum frequency of the impulse wavelet and directly with minimum velocity value in the given model. The LSRTM wavefield extrapolation usually uses the two-dimensional constant density acoustic wave equation, by considering the change of velocity field distribution, and converts it to the corresponding pseudodepth domain, so as to solve the oversampling problem in the true depth domain. For each point in the Cartesian coordinate system, there is a corresponding point in the pseudo depth domain. Therefore, we can interpolate and remodel the reconstructed finite difference modelled wavefield in the new coordinate system through the Cartesian-to-pseudodepth mapping function. Regardless of the applied finite difference algorithm and boundary conditions, wavefield extrapolation in pseudodepth domain can ensure high accuracy and efficiency. Through the test of synthetic and actual data, compared with the traditional LSRTM results, pseudodepth domain LSRTM shows great potentiality in amplitude preserving imaging. On the other hand, pseudodepth domain LSRTM has great advantages in computational efficiency and ensures computational accuracy.Masters基于笛卡尔的最小二乘逆时偏移（LSRTM）旨在通过计算和求解Hessian矩阵获得相对高分辨率和保幅的成像。此外，共轭梯度算法被证明是一种有效的迭代方法，这使得传统的LSRTM在实际数据处理应用中是可行的。LSRTM的每个迭代过程包括两个主要部分；第一部分是波场的正演模拟，第二部分是波场的反向传播。然而，这两部分的计算需要花费大量时间，并且在计算过程中会出现过采样效应。本论文对伪深度域LSRTM方法进行了研究，给出了该方法波场外推的信息，获取了保幅的图像，并且该方法有较低的内存和时间成本。
地震勘探面临的地下介质通常包括低速体、高陡构造和孔隙裂隙单元。在模拟这些介质中的地震波场时，为了保证有限差分法的模拟精度和计算稳定性，需要非常小的网格间距，这导致了传统的笛卡尔坐标系有限差分正演模拟方法的过采样问题。为了克服这一问题，将伪深度域算法应用于LSRTM，以提高其计算效率。伪深度域波场稳定是因为引入了映射函数和速度，还有垂直轴算子，并将有限差分解从时间域转换为频率域。稳定性和收敛性分析表明，除了映射速度之外，黎曼轴的空间导数还应该通过傅里叶伪谱方法来近似，该方法使用一种特殊的类高斯脉冲函数来生成有限差分算子内复数震源项的向量矩阵，它是初始输入速度模型的微分形式，控制相关黎曼有限差分算子的CFL条件。合成数据的例子表明，这种方法在推导平滑的黎曼波场时更加稳定和高效，同时保持了Claerbout地下反射体的定位原则，也为新纵轴选择了合适的采样率，该采样率与脉冲小波的最大频率成反比，与给定模型中的最小速度值直接相关。
LSRTM波场外推法采用二维常密度声波方程，通过考虑速度场分布的变化，将其转换为相应的伪深度域，从而解决真深度域的过采样问题。对于笛卡尔坐标系中的每个点，伪深度域中都有一个对应点。因此，我们可以通过笛卡尔到伪深度映射函数，在新坐标系下对重建的有限差分模拟波场进行插值和重塑。无论采用何种有限差分算法和边界条件，伪深度域的波场外推都能保证较高的精度和效率。通过对合成数据和实际数据的测试，与传统的LSRTM结果相比，伪深度域LSRTM在保幅成像方面显示出巨大的潜力。另一方面，伪深度域LSRTM在计算效率和计算精度方面也有很大优势
Fibropapillomatosis in sea turtles: an overview
No full textComo partícipes de ecosistemas, las tortugas marinas se enfrentan a una amplia gama de factores ambientales y de origen antropogénico que pueden ocasionarles daños, lesiones, enfermedades y en casos graves, la muerte. En el caso de las enfermedades, la fibropapilo- matosis es el padecimiento más estudiado en estos quelonios. Esta enfermedad se caracteriza por la presencia y desarrollo de tumores epiteliales benignos que pueden afectar a una tortuga enferma, está asociada con una infección por el alfaherpesvirus quelónido 5, y en casos graves puede ser fatal para las tortugas. El objetivo de este trabajo fue revisar el cono- cimiento actual sobre la fibropapilomatosis en tortugas marinas y proponer herramientas funcionales y validadas para su identificación, manejo, tratamiento y rehabilitación. Este documento reúne la información necesaria para conocer las características de los tumores que se presentan durante esta enfermedad en las tortugas marinas y ayuda a entender el daño que produce en los organismos afectados, lo cual permitirá actuar en eventos de fibropapilomatosis a nivel nacional e internacional. La información generada propone complementar las evaluaciones de salud de tortugas marinas, así como fortalecer los pla- nes de manejo y generar las estrategias de conservación pertinentes para estas especies y los ecosistemas donde se distribuyen.As participants of ecosystems, sea turtles face a wide range of environmental and anthro5, and in severe cases can be fatal to turtles. This document aimed to review the current knowledge on fibropapilloma- tosis in sea turtles and propose functional and validated tools for its identification, management, treatment and rehabilitation. The gathered information allows to identify the characteristics of the tumors that occur during this disease in sea turtles, which will allow to act in fibropapillomatosis events at the national and international level. The generated information will help complement sea turtle health assessments, as well as strengthen the management plans and generate the pertinent conservation strategies for these species and the ecosystems where they are distributedpogenic factors that can cause damage, injury, disease and in serious cases, death. Among the diseases, fibropapillomatosis is the most studied condition in these chelonians. This disease is characterized by the presence and development of benign epithelial tumors that can affect a diseased turtle, It is associated with an infection by chelonid alphaherpesvirusPublishedReferee
Application of Data Science for the reconstruction of time series of meteorological variables in the Islas del Rosario (Colombian Caribbean), between the years 2013-2021
No full textEste estudio revisa dos series de tiempo de variables meteorológicas medidas por una estación automática ubicada en Islas del Rosario (Caribe colombiano), perteneciente a la Red de Medición de Parámetros Oceanográficos y de Meteorología Marina (RedMpomm) de la Dirección General Marítima (Dimar). Las series de tiempo corresponden a datos de temperatura ambiente y magnitud del viento en el periodo 2013-2021, los cuales presentan algunos valores faltantes. El objetivo del estudio fue desarrollar un modelo que permitiera completar automáticamente los diferentes vacíos existentes en las series de tiempo, utilizando las ventajas de la ciencia de datos al completar información con valores estimados. La importancia de obtener series reconstruidas radica en lograr tener bases de datos más sólidas para ser utilizada en los trabajos de investigación y académicos que realiza la Dimar. La metodología desarrollada consistió en el uso de imputación de medianas a partir de datos existentes sobre fechas y horas asociadas a valores faltantes, todo esto mediante el uso de desfases de datos e información complementaria como relaciones de periodicidad sobre el conjunto de datos. Los resultados mostraron que se logró implementar una metodología capaz de estimar el valor más adecuado para completar las diferentes series temporales, la cual constituye una primera aproximación para la reconstrucción de datos meteorológicoThis study reviews two time series of meteorological variables measured by an automatic station located in Islas del Rosario (Colombian Caribbean), belonging to the Network for Measurement of Oceanographic Parameters and Marine Meteorology (RedMpomm) of the General Maritime Directorate (Dimar). The time series correspond to data of air temperature and wind magnitude in the period 2013-2021, which present some missing values. The objective of the study was to develop a model that would automatically reconstruct missing values in the time series, using the advantages of data science to complete information with estimated values. The importance of obtaining reconstructed series lies in having more solid databases to be used in the research and academic work carried out by Dimar. The methodology developed consisted of the use of imputation of medians from existing data on dates and times associated with missing values, all this through the use of data lags and complementary information such as periodicity relationships on the data set. The results showed that it was possible to implement a reliable methodology capable of estimating the most appropriate value to complete the different time series, which constitutes a first approximation for the reconstruction of meteorological data.PublishedNon Referee
Allocation and co-location model for maritime activities related to marine and coastal management, Bolívar department, Colombia
No full textLa tendencia al crecimiento del sector marítimo debido al aumento en la población, al desarrollo urbanístico y a la industrialización, han generado la diversificación de usos en las zonas marino-costeras, causando conflictos por la relación uso/espacio. Por esto la Dirección General Marítima colombiana (Dimar), ha desarrollado una metodología que permite analizar las condiciones futuras para el desarrollo de actividades marítimas en las aguas y costas colombianas, a través del Ordenamiento Marino Costero: Visión de Autoridad Marítima (OMC:VAM), que en su proceso metodológico plantea el modelo de asignación y colocalización (MAYC), el cual busca establecer la localización espacial de las áreas más adecuadas para actividades marítimas, teniendo en cuenta criterios técnicos, ambientales y variables de eficiencia/eficacia establecidos por la Dimar, tipo de actividad marítima, disponibilidad y cobertura de la información. El modelo se aplicó en la zona marino-costera del departamento de Bolívar, encontrando, con base en los criterios seleccionados para las diferentes actividades, que un 90 % del área es apta para llevar a cabo actividades de acuicultura, un 84 % es apta para instalación de parques eólicos y un 0.39 % de área es adecuado para construcción de marinas-embarcaderosThe growth trend of the maritime sector due to the increase in population, urban development and industrialization has generated a diversification of uses in marine and coastal areas, causing conflicts due to the use/space interaction. For this reason, the Colombian General Maritime Directorate (DIMAR in Spanish) has developed a methodology that enables the analysis of future conditions for the development of maritime activities in Colombian waters and coasts, through its Marine and Coastal Management with a Maritime Authority Vision (MCM:MAV), using the Allocation and Co-location Model (MAYC in Spanish), which seeks to establish the most appropriate spatial location for maritime activities, considering technical and environmental criteria and efficiency/effectiveness variables established by DIMAR, depending on the maritime activity type, and the availability and coverage of the information. The model was applied in the marine and coastal area of Bolivar Department, finding, based on the criteria selected for the different activities, that 90 % of the area is suitable to carry out aquaculture projects, 84 % for offshore wind farms, and 0.39 % for the construction of marinasPublishedNon Referee
La Ciguatera Un riesgo potencial para la salud humana: Preguntas frecuentes. 3ra Edición.
No full text¿Es acertado embesƟr a los lectores con 24 preguntas sobre la Ciguatera? ¡Sin lugar adudas! La Ciguatera es un problema serio, un peligro demostrado, una intoxicación alimentaria originada por el consumo de pe- ces, mayoritariamente en laƟtudes intertropicales, y que se distribuye en diferentes zonas marinas a lo ancho de todo el planeta. La Ciguatera afecta a numerosas personas, y no temporalmente, sino con persistencia, de forma crónica, al- terando la salud, el Ɵpo de vida y el humor de las personas intoxicadas y de sus familias. La propuesta que nos hacen Gilma Delgado, Lisbet Díaz, Gustavo Arencibia y José Ernesto Mancera, cuatro cienơfi- cos, cuatro invesƟgadores de reputación internacional, es una apuesta de futuro basada en la prevención como estrategiaPublishedReferee
О террасах на берегу Териберской губы Баренцева моря (Кольский полуостров)
No full textThe paper considers the results of the study of modern terraces on the coast of the Lodeyny Peninsula in the Barents Sea. According to field observations, decoding of space and geodetic maps and volumetric modeling, signs of three terraces have been identified. Two terraces having a rear seam, a cliff, a brow and horizontal platforms have been studied in more detail. The rear seams are located at 7 and 30 m, and the edges at 10 and 40 m above the sea level. The third terrace is confined to the level of 40–60 m, and has not been studied in detail. According to estimates, the first two terraces were formed about 3,300 and 6,000 years ago respectively. The 1st terrace characterizes the period of slow land rise by 10 m, at the speed up to 3 mm/year, which began about 3,300 years ago and continues to the present. It is characterized by a uniform sea retreat of about 15 mm/year. The erosion products of this terrace are common in the lateral zone and represent modern marine sediments, including beaches forming a new terrace. The 2nd terrace characterizes to the dynamics of rapid land rise by 30 m at a speed of about 11 mm/year, which occurred in the period from 6,000 to 3,300 years ago. The erosion products of this terrace are most common on the coast and are found at a distance of 100 m to 2–3 km from the shore. It is assumed that the speed of movement of the coastline during the retreat of the sea was different and reached up to 900 mm/year. According to the authors, preliminary data indicate the instability of the territory and the manifestation of block movements, which may have a negative impact on the development of infrastructure.В статье рассмотрены результаты изучения современных террас на побережье Баренцева моря в районе п-ва Лодейный. По данным натурных наблюдений, дешифрирования космических и геодезических карт и объемного моделирования выявлены признаки трех террас. Более детально изучены две террасы, у которых присутствуют тыловой шов, обрыв, бровка и горизонтальные площадки. Тыловые швы располагаются на отметках 7 и 30 м, а бровки – на отметках 10 и 40 м над уровнем моря. Третья терраса приурочена к уровню 40–60 м, детально не изучена. По расчетным данным первые две террасы образовались около 3 300 и 6 000 лет назад. 1-я терраса характеризует период медленного подъема суши на 10 м со скоростью около 3 мм/год, начавшийся около 3 300 лет назад и продолжающийся по настоящее время. Продукты размыва этой террасы распространены в латеральной зоне и представляют современные морские отложения, в том числе пляжи, формирующие новую террасу. 2-я терраса характеризует динамику быстрого подъема суши на 30 м со скоростью около 11 мм/год, произошедшего в период от 6 000 до 3 300 лет назад. Продукты размыва этой террасы имеют наибольшее распространение на побережье и встречаются на расстоянии от 100 м до 2–3 км от берега. Предполагается, что скорость перемещения береговой линии при отступлении моря была различной и достигала до 900 мм/год. По мнению авторов, предварительные данные свидетельствуют о нестабильности территории и проявлении блоковых подвижек, что может оказать негативное воздействие на развитие инфраструктуры.PublishedReferee
Contribution à l’inventaire des espèces d’Elasmobranches dans le golf de Ghazaouet (mer d’Alboran, ouest Algérie).
No full textLa présente étude fait partie du projet « Contribution à l’inventaire, l’estimation de l’abondance et la mise en évidence de l’impact de la pêche (tous segments confondus) sur les Elasmobranches dans le golf de Ghazaouet (mer d’Alboran – ouest Algérie) », inscrit dans le cadre du MAVA Species Project. Elle vise à actualiser la liste des espèces appartenant à l’embranchement des Elasmobranches au niveau du golf de Ghazaouet. Pour ce faire, cinq approches principales et complémentaires ont été adoptées dans deux ports situés à l'ouest de la côte algérienne (Beni Saf et Ghazaouet), sur une période s’étalant sur vingt-deux mois (de février 2020 à septembre 2021). Les résultats montrent que pendant la période d'étude, vingt- six (26) espèces d'élasmobranches ont été recensées, ces espèces se répartissent entre 10 espèces de raies, 15 espèces de requins et 01 espèce de chimère. Cependant, Galeus melastomus et Scyliorhinus canicula sont les deux espèces les plus abondantes dans les pêcheries. Ainsi, la présence de trois espèces de requins classées en danger d’extinction par l’UICN a été révélée. Alors, la proposition de mesures de gestion efficaces basées sur la conservation des espèces vulnérables d'élasmobranches est indispensable.This study is part of the project "Contribution to the inventory, the estimate of the abundance and the highlighting of the impact of fishing (all segments combined) on Elasmobranchs in the Gulf of Ghazaouet (Sea of 'Alboran – ouest Algérie)', listed under the MAVA Species Project. It aims to update the list of species belonging to the Elasmobranchs phylum at the Gulf of Ghazaouet. To do this, five main and complementary approaches have been adopted in two ports located on the west of the Algerian coast (Beni Saf and Ghazaouet), over a period spanning twenty-two months (from February 2020 to September 2021). The results show that during the study period, twenty-six (26) species of elasmobranchs were identified; these species are divided between 10 species of rays, 15 species of sharks and 01 species of chimera. However, Galeusmelastomus and Scyliorhinus canicula are the two most abundant species in the fisheries. Thus, the presence of three species of sharks classified as endangered by the IUCN has been revealed. Therefore, the proposal of effective management measures based on the conservation of vulnerable elasmobranch species is essential.Références bibliographiques, Figures, Tableaux.PublishedReferee