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Summary of the National Symposium on the Hydrological Applications of Weather RadarThese Proceedings do not produce the abstracts of the Symposium but summarize the requirements of users and potential users of weather radar as those were expressed at the venue; document the Workshops conducted by Professors Collier, Cluckie and Austin during the Symposium; present the finding s from the Working Groups which considered various uses of weather radar in New Zealand, and contain a program and a complete list of names and addresses of people who attended the Symposium (Appendices 1 and 2).
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Thermohaline characteristics of the Azov Sea in the summer season of 1989–2021 and how they are affected by the runoff of the Don and Kuban RiversВодные биоресурсы и среда обитанияConsiderable inter-annual variations of water temperature and salinity in the Azov Sea necessitate their constant monitoring. Following the numerous studies undertaken in this area, this work presents the specific features of inter-annual changes in temperature and salinity of the sea surface layer, averaged for the summer seasons of 1989–2021 both for the Azov Sea (excluding Taganrog Bay) and for its various areas; two representative time spans, 1989–2004 and 2005–2021, have been identified. The first time span was characterized by a relatively wide variation range of the temperature and by its decreased values, as well as by the decrease in the salinity. During the second time span, an increase in the both temperature and salinity of the sea surface layer occurred in the sea and its regions, which was induced by the increase in the air temperatures in the area and by the reduction of the relatively cold Don River runoff after 2005 in the case of the first parameter, and, for the second parameter, it resulted from the decrease in the runoff of the both Don and Kuban Rivers. Correlation analysis of the series of the summer temperature and salinity values by area and for the sea on the whole as they relate to the annual and maximum runoff of the Don River (Razdorskaya) and to the annual runoff of the Kuban River (Krasnodar and the river mouth) for 1989–2021 has shown the absence of the significant relationship with temperature and its presence with salinity both for the sea and for most of its regions at the confidence level of 99 % for the Don River runoff and 95 % for the Kuban River runoff.
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Overview of major water oil spill management techniques and evaluation of their efficiencyВодные биоресурсы и среда обитанияThe extraction, transportation and sale of “black gold” is an integral component of the sustainable economic development of the Russian Federation. Due to the remoteness of most hydrocarbon extraction sites, adverse climate-related impact on the timing of the transfer of extracted resources, and high operational loads on the equipment, the threat of technogenic environmental pollution by oil and its products persists. Despite the existing options for timely prevention and efficient management of such events, the choice of the optimal clean-up method remains open. This article identifies the main methods of dealing with oil spills in the aquatic environment, provides their brief description, and indicates their efficiency. The authors present the technical solution (a specialized carrier) they are developing, which combines the features of the three main methods for eliminating artificial oil pollution (mechanical, physico-chemical, and biological) of the water surface. The proposed technical solution, in the authors’ opinion, will allow for optimization of the clean-up practices for technogenic hydrocarbon spills.
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Ecological risk assessment principles applied to oil spill response planning in the San Francisco Bay Area.This report describes the efforts of a group of individuals involved in or concerned with the environmental impacts of oil spills and oil spill response in San Francisco Bay. Participants affiliated with various federal and state government agencies, the response industry, and environmental organizations were invited to utilize their individual familiarity with the issues in discussion and consensus-building exercises. The conclusions and recommendations do not commit any governmental, industry, or environmental organization in the San Francisco Bay area to a particular course of action or policy. This report was disseminated to participants for review, and their comments have been addressed in the final report. Some participants requested that the report be given wider dissemination in draft form to allow review by parent organizations and other non-participants. Although the sponsors agree that wide dissemination of the final document is essential, dissemination of the draft report beyond actual participants was not encouraged, since the report represents the consensus conclusions of the participants. Nevertheless, some comments were received from organizations, rather than participants. Some comments regarding style and grammar from non-participants were incorporated into the final report, but comments that altered the final consensus conclusions reached by participants were not incorporated. Those comments are relevant, however, and they serve as an excellent starting point for future discussion at the Area Committee and Regional Response Team levels of improved response capabilities in the San Francisco Bay Area. They are, therefore, included as Appendix R. This report does not endorse the use of dispersants or any other response measure on a specific spill incident in San Francisco Bay or elsewhere, but it does indicate that that more emphasis on integrated response measures, including unconventional options, might be of benefit. The results of this ERA are intended as a starting point for further, more focused study by those organizations potentially benefiting from spill mitigation strategies.
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Ecological Risk Assessment Consensus Workshop Environmental Tradeoffs Associated With Oil Spill Response Technologies Santa Barbara Channel: A Report for Regional Response Team IX.In March and April of 2002, Regional Response Team (RRT) IX sponsored a workshop to evaluate the relative risk to natural resources from various oil spill response options (on-water mechanical recovery and dispersant application) in comparison to natural recovery. The spill scenario involved the release of 10,000 barrels of Intermediate Fuel Oil (IFO) 180 in the northern end of the Santa Barbara Channel, under conditions which threatened the interior coastline of the Channel Islands. The workshop involved two meetings during which participants received briefings on the expected results of the spill with and without response options, the relative effectiveness of on-water mechanical recovery, dispersants and on-water in situ burning, and the risks and benefits of these response options to the habitats and natural resources of the area. The participants were then divided into three focus groups and were asked to develop relative risk scores for the various alternatives, using standard analytical protocols outlined in the Coast Guard guidebook entitled "Developing Consensus Ecological Risk Assessments: Environmental Protection in Oil Spill Response Planning. A Guidebook." The scores from the three groups were then compared and a composite risk matrix developed which represented the overall consensus of the entire group. At the conclusion of the second meeting, the group developed a list of lessons learned and recommendations for the RRT and local Area Committee which they felt would improve local response planning efforts.
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Ecological Risk Assessment Consensus Workshop Environmental Tradeoffs Associated With Oil Spill Response Technologies Casco Bay, Maine: A Report to the Maine/New Hampshire Area Committee.In June 2003, the United States Coast Guard (USCG) District 1 sponsored a workshop to evaluate the relative risk to natural resources from various oil spill response options (on-water mechanical recovery, dispersant application, and shoreline removal) compared to natural recovery. The spill scenario involved a release of approximatelyl,200 barrels (50,000 gallons) of Brent crude near the southern edge of Casco Bay, under conditions which threatened some interior islands and some exterior coastline. Participants examined this scenario during one accelerated, two-and-a-half day meeting during which they received briefings on the expected results of the spill with and without response options; the relative effectiveness of on-water mechanical recovery and dispersants; and the risks and benefits of these response options to the area's habitats and natural resources. Participants divided into two focus groups and developed relative risk scores for three alternatives, using standard analytical protocols outlined in the Coast Guard guidebook: Developing Consensus Ecological Risk Assessments: Environmental Protection in Oil Spill Response Planning. A Guidebook. Scores from each group were then compared, and a composite risk matrix developed to represent the overall consensus. At the conclusion of the workshop, participants developed lessons learned along with recommendations for the Regional Response Team (RRT) and local Area Committee to improve local response planning efforts.
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Net Environmental Benefit (Ecological Risk) Assessment Consensus Workshop Environmental Tradeoffs Associated With Oil Spill Response Technologies Upper Mississippi River, Pools 7 and 19: A report to USCG District 8 and US EPA Region 5.In March and April 2004, the United States Coast Guard (USCG) District 8 and the US Environmental Protection Agency (US EPA) sponsored two workshops in separate locations along the upper Mississippi River to evaluate the relative risk to natural resources from various oil spill response options. The first, held in La Crosse, Wisconsin, examined a Canola oil spill from a railroad accident into Pool 7 of the Mississippi River. The second, held in Keokuk, Iowa, examined a pipeline rupture that released West Texas Intermediate crude oil into Pool 19. Both exercises were assumed to occur in the fall, and so the primary concern was for protection of migrating waterfowl. In both exercises, there were also concerns about effects on protected species of mussels. There were local differences in viable response strategies which appeared to be acceptable. For example, bird hazing using boats appeared both feasible and attractive in Pool 7, but was not considered practical in Pool 19. Conversely, there was interest in shoreline in-situ burning in Pool 19, but not in Pool 7 because of the population density in the areas where the oil would collect. In both areas the spill affected most of the pool within the first 24 hours, so many of the impacts were judged to be unavoidable. Shoreline cleaning and nearshore recovery of pooled oil was judged effective in both areas in preventing reoiling, but participants were concerned about additional damage to sensitive habitats in both workshops. In Pool 19, participants felt that an early deployment of deflection booming offered the best option to protect waterfowl. In both areas, the ecological damage to migrating populations of waterfowl could be serious if the response options were not rapidly applied and effective, since very large populations of birds, in some cases the majority of the continental population, use the pools during migration.
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Ecological Risk Assessment Consensus Workshop Environmental Tradeoffs Associated With Oil Spill Response Technologies Delaware Bay: A Report to the US Coast Guard, Sector Delaware Bay.In January/February 2006, the United States Coast Guard (USCG) Sector Delaware Bay sponsored a workshop whose purpose was twofold: First, in response to the M/V Athos 1 oil spill in November 2004 and the ongoing work of the Area Committee, the USCG sought to bring together and educate the various non-spill response resource managers and scientist in the Delaware Estuary. Secondly, the workshop allowed the participants the opportunity to evaluate the relative risk to natural resources from various oil spill response options (on-water mechanical recovery, dispersant application and on-shore mechanical recovery) compared to natural recovery.
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Ecological Risk Assessment Consensus Workshop Environmental Tradeoffs Associated With Oil Spill Response Technologies Maryland Eastern Shore: A report to Commander, US Coast Guard Activities, Baltimore.In June and July of 2002, U.S. Coast Guard (USCG) Activities Baltimore sponsored a workshop to evaluate the relative risk to natural resources from various oil spill response options ( on-water mechanical recovery with shoreline protection, on-shore in situ burning, on-shore mechanical recovery and dispersant application) in comparison to natural recovery. The spill scenario involved the release of 2,000 barrels of Number 6 Fuel Oil near the north end of Kent Island in Tolchester Channel under conditions which threatened the Eastern Shore of the Chesapeake Bay in the vicinity of the Eastern Neck Wildlife Refuge. The workshop involved two meetings during which participants received briefings on the expected results of the spill with and without response options, the relative effectiveness of the various response options, and the risks and benefits of these response options to the habitats and natural resources of the area. The participants were then divided into three focus groups and were asked to develop relative risk scores for the various alternatives, using standard analytical protocols outlined in the USCG guidebook entitled "Developing Consensus Ecological Risk Assessments: Environmental Protection in Oil Spill Response Planning. A Guidebook." The scores from the three groups were then compared and a composite risk matrix developed which represented the overall consensus of the entire group. At the conclusion of the second meeting, the group developed a list of lessons learned and recommendations for Regional Response Team (RRT) 3 and USCG Activities Baltimore which they felt would improve local response planning efforts.
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Ecological Risk Assessment Consensus Workshop Environmental Tradeoffs Associated With Oil Spill Response Technologies Upper Florida Keys: A Report to USCG District 7..In late August 2002, the United States Coast Guard (USCG) District 7 sponsored a workshop to provide oil spill response training and to discuss the relative risks to natural resources from various oil spill response options (on-water mechanical recovery, dispersant application and to a lesser extent, shoreline protection) in comparison to natural recovery. These discussions were based on a spill scenario involving the release of 100,000 gallons of Intermediate Fuel Oil (IFO) 180 near Molasses Reef in the Florida Keys, under conditions which threatened mainland shoreline habitats, a number of offshore islands, and a variety of valuable subtidal habitats. After participants received briefings on the expected results of the spill with and without response options, the relative effectiveness of two options, on-water mechanical recovery and dispersants, was evaluated. Participants discussed the risks and benefits of these response options to the habitats and natural resources of the area. The participants were then divided into three focus groups and asked to develop relative risk scores for the various alternatives, using standard analytical protocols outlined in the USCG guidebook entitled "Developing Consensus Ecological Risk Assessments: Environmental Protection in Oil Spill Response Planning. A Guidebook." The scores from the three groups were then compared and a composite risk matrix developed which represented the overall consensus of the entire group. After the primary scenario was examined, two additional scenarios (one near the entrance of Biscayne Bay and one near Looe Key) were evaluated to examine the general applicability of the discussions for the Molasses Reef scenario. At the conclusion of the meeting, the group developed a list of lessons learned and recommendations for the RRT and local Area Committee that they felt would improve local response planning efforts. In general, participants concluded that on-water mechanical recovery, in the scenario under consideration, was unlikely to provide much protection for shoreline habitats. Dispersant use, if effective, did provide such protection, but with some increased risk to coral habitat in shallow water (less than 5 meters). This risk did not extend to deeper habitats, and was a concern in only limited areas. The participants recommended reexamining the current dispersant preauthorization limits to see if they could be made less restrictive.
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Ecological Risk Assessment Consensus Workshop Environmental Tradeoffs Associated With Oil Spill Response Technologies Mexico - United States Pacific Coastal Border Region: A report to the US Coast Guard, District 11.In June/July 2006, the United States Coast Guard (USCG) District 11 sponsored a workshop to evaluate the relative risk to natural resources from various oil spill response options (on-water mechanical recovery, dispersant application, and on-shore mechanical recovery) compared to natural recovery, which in the context of the workshops refers to oil removal by natural processes only. The spill scenario involved a release of approximately 70,000 gallons of Intermediate Fuel Oil (IFO) due to an accident five nautical miles west of Point Loma, CA. The hypothetical date for the release was late June. The workshop involved participants from both the United States (US) and Mexico, and was designed to emphasize cooperative decision-making when a spill in US waters threatened shoreline resources in both countries and when consideration of dispersants would lead to increased risk to valuable offshore resources in Mexican waters. The workshop consisted of two three-day workshops separated by approximately one month. At the initial meeting three focus groups analyzed natural recovery and on-water mechanical recovery. At the second workshop the groups evaluated dispersant use at two levels of effectiveness (75% and 25%) and on-shore mechanical recovery. The participants concluded that on-water mechanical recovery, in this scenario, was unlikely to be effective in reducing shoreline impacts. While dispersants offered some benefits to the shoreline, the groups did not agree as to the magnitude. All groups concluded that protection of the Tijuana Slough was a high priority, and that the current strategy of placing a berm across the entrance to prevent contamination was a critical element of the response plan. If this was not successful cleanup would be very difficult, if not impossible. Environmental concerns were largely driven by the risk to sea birds, and secondarily to intertidal invertebrates. When dispersants were used there was an increased risk to sensitive offshore habitats and water column resources, especially around the Coronado Islands, but the concerns were not ranked above a moderate level by any group. Participants felt that additional cooperative efforts of this type were important, and helped build the international interactions necessary for successful planning and response. They also emphasized that, if dispersants are to be considered as an option, there must be extensive planning and exercises to familiarize stakeholders with the issues, so that decisions can be made in a timely fashion.
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Ecological Risk Assessment Consensus Workshop Environmental Tradeoffs Associated With Oil Spill Response Technologies Mexico - United States Gulf of Mexico Coastal Border Region: A report to the US Coast Guard, Sector Corpus Christi.In October/November 2007, the United States Coast Guard (USCG) Sector Corpus Christi hosted a workshop to provide training in dispersant use in oil spills and to evaluate the relative risk to natural resources from various oil spill response options including no response (natural recovery), on-water mechanical recovery, dispersant application and on-shore mechanical recovery. The workshop involved participants from both the United States (US) and Mexico, and was designed to emphasize cooperative decision-making when a spill threatens shoreline resources in both countries. The workshop consisted of two three-day workshops separated by approximately two weeks. The spill scenario was designed to present participants a situation with similar threats and decisions on both sides of the US-Mexico border. In the scenario, oil spilled approximately 3 miles offshore and the potential response actions were evaluated to determine their influence on the impact of the spill on sensitive coastal and estuarine resources. According to the scenario, after an explosion in the engine room, a tanker carrying 1.2 million gallons of Angola Soyo Crude Oil had two releases of oil. The first spill of 60,000 gallons was expected to come ashore primarily in the US, and, approximately 42 hours later, a second spill released an additional 80,000 gallons of oil expected to come ashore in Mexico. Participants were divided into four focus groups to evaluate the relative risks and benefits of the response options. Two groups, comprised of US participants, focused on the first spill (which affected the US) and two groups, comprised primarily of Mexican Navy personnel, examined the second spill (which affected the coastline in Mexico). After evaluating the options within the parameters presented for this scenario, the groups concluded that because of the size of the spill, there were potential serious risks to both shoreline and shallow water habitats. On-water mechanical recovery was viewed as being of limited utility in this scenario. Dispersant use raised serious concerns but did provide some benefit to shoreline and intertidal habitats. Likewise, on-shore mechanical recovery was beneficial to some habitats, but raised serious concerns in mangrove areas. The size of the spill made it unlikely that any alternative response would be effective in preventing serious impacts. The highest concern was for estuarine habitats. At the end of the workshop participants developed a list of lessons learned and recommendations for future oil spill response planning in the area.
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Sea Links. The Planktonic Marine Food Web"Sea Links" is designed to be used as a supplementary resource to support the teaching and learning of Science and Biology at Level 7 (Year 12). This resource also complements the "Sea and Learn" programme resources. The planktonic (ocean's water column and the organisms within it) food web is the resource's focus of study. It is intended for use with students at Years 11, 12 and 13, though it may be appropriate at other levels too. As they study the marine ecosystem, they will be rewarded by a number of surprises, including the variety of animals, and the unexpected direction of the energy flow that may occur when nutrient levels are low.
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Ostracoda (Crustacea) biodiversity: a taxonomic and functional approach.The impacts of human actions, as deforeations, pollution and introduction of species have been causing negative effects on the environment. The extinction of species, and change of distribution range, are some of them, especially in the aquatic environment were it is observed a hogh richness compared to its extension. Thus, the knowledge about biodiversity is of extreme importance conservation of ecosystems. Ostracods are one example of a group constantly affected but ill studied. It was performed a revision of Cyprettinae s.l. from circumtropical regions, using morphological taxonomy. The first step in the revision of Cyprettinae s.l. was redescribe the type species of Cypretta Vavra, 1895 from the original type material, discuss the morphology and diagnosis of the genus. After that it was described two new species from Pseudocypretta Klie, 1932 genus from South Africa and Brazil; and described a new genus and four new species from Brazil. With the redescription of the type species of the Cyprettathe diagnosis characters for the species and genus were delimited. Analyzing the features of the new species of Pseudocypretta this genus was moved from the Cyprettinae subfamily to the Cypridopsinae subfamily, and expanded the distribution of this genus to the Afrotropical and Neotropical regions. The new genus and new species were recorded from the four main floodplain of Brazil and were designated to the Cyprettinae subfamily. Both Cypretta, Pseudoypretta and new genus are characterized by presence of septas in its valves, however they vary in level of development (complete or incomplete) and disposition along the margins of the valves. Using a database of ostracods distribution and ecological niche modelling (ENMs) the effects of climate change were evaluated to the functional diversity of ostracods in the South Cone of South America, in the moderate-optimistic and pessimistic scenarios of 2050 and 2080. It is projected that the ostracod functional diversity will suffer a gradual reduction in 2050 and 2080on bothscenarios of carbon emission, but especially in the pessimistic scenario of 2080. The results highlight the importance of evaluate the functional diversity for ostracod conservation, since several areas marked to have low taxonomic richness supported intermediate and high levels of functional diversity.
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Biology features and parasites study of Mullet (Mugilidae) caught from Algerian coast.Hippocampus: Algerian journal of fisheries and aquaculture research.Mugilidae are one of the most farmed fish in Algerian freshwater aquaculture. The objective of the paper was to study the biological and parasitological characteristics of Mugilidae caught in Algerian coast. Six species were identified Mugil cephalus (Linnaeus, 1758), Liza ramada (Risso, 1827), Liza aurata (Risso, 1810), Liza saliens (Risso, 1810), Chelon labrosus (Risso, 1827) and Oedalechilus labeo (Cuvier, 1829), using morphological observation. Mullet fed on a variety of diet items including detritus, polychaetes, and sediments. Parasite groups recovered (from what) were identified as Nematoda, Monogenea, Copepoda, Ectoparasites, Cestoda, Digenea, and Cysts. Overall infection prevalence (%), mean intensity, and abundance values were 60%, 40.63, and 24.38, respectively. A significant correlation was observed (R>0.7) between fish size or weight and prevalence. Therefore, a sanitary treatment for the mullets before ponds introduction is necessary in order to prevent parasite transmission to cultured fish.
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Contribution à l'étude de la croissance relative en aquaculture extensive d'une crevette pénéide: cas de Penaeus (Melicertus) kerathurus de la lagune El- Mellah (Algérie).Hippocampus: Algerian journal of fisheries and aquaculture research.Dans le présent travail, nous avons examiné la croissance relative de la crevette royale Penaeus kerathurus issue de la pêche commerciale de la lagune d’El Mellah. Les relations allométriques reliant les différentes parties du corps des crevettes mâles et femelles expriment toutes sans exception une forte allométrie minorante. Les résultats obtenus dans cette étude concordent avec ceux précédemment décrits chez plusieurs populations de Penaeus kerathurus et ils constituent un nouvel élément de preuve en faveur de l'uniformité génétique de l’espèce le long de son aire de répartition méditerranéenne.
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Diagnose rapide et estimation de la production du barrage de Boukourdane.Hippocampus: Algerian journal of fisheries and aquaculture research.Pour évaluer la qualité d'un milieu aquatique, les scientifiques utilisent des indices basés sur la physico-chimie, les algues phytoplanctoniques, et les invertébrés. Dans certains cas ils utilisent les poissons ou « indice poisson » qui prend en considération les communautés de poissons comme finales indicateurs biologiques et intégrateurs finals. Dans ce travail, la méthode de « diagnose rapide », mise au point par le CEMAGREF en 1990, et qui a été adaptée en 2002 par Boudjenah aux conditions algériennes, qui a été appliqué, à des données et résultats de travaux réalisés par d’autres chercheurs universitaires au niveau du Barrage de BOUKOURDANE, récoltées dans la bibliographie. La méthode de diagnose rapide, prend en considération les paramètres physico-chimiques de l'eau, du sédiment et d'une partie des peuplements biologiques (phytoplancton), ces paramètres sont ensuite traduits en indices basés sur la situation trophique des compartiments de l'écosystème aquatique. Le calcul des indices nous permet de situer ensuite le plan d'eau sur la gamme des niveaux trophiques : oligotrophes, mésotrophes, eutrophes. (Barbe et al, 1990). Ce classement donne enfin la possibilité d'estimer la production du barrage de BOUKOURDANE afin de prévoir et d'optimiser son exploitation.
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Contribution à l’inventaire des espèces d’Elasmobranches dans le golf de Ghazaouet (mer d’Alboran, ouest Algérie).Hippocampus: Algerian journal of fisheries and aquaculture research.La 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.
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Contribution à l’étude bioéconomique de la pêcherie chalutière (Cas du Mullus barbatus) de la région centre du bassin algérien.Hippocampus: Algerian journal of fisheries and aquaculture research.Une approche bioéconomique de la pêcherie chalutière de la baie de Bou Ismail (région centre de l’Algérie), est effectuée sur le rouget de vase (Mullus barbatus). Il en ressort de la distribution des fréquences de taille de l’espèce, des classes entre 9,4 cm et 22,9 cm, avec une moyenne de 16,22 cm. Trois groupes d’âges sont mis en évidence par les méthodes Bhattacharya et NORMSEP (Bhattacharya amélioré). A partir des résultats du programme ELEFAN I, les valeurs retenues pour K et L∞ sont respectivement 0.56 an-1 et 29.00 cm. L’étude de la relation taille /poids de Mullus barbatus montre qu’elle est de type isométrique avec une croissance relativement rapide de l’espèce. Les mortalités totales sont importantes avec des coefficients de mortalités naturelles M/an faibles par rapport aux coefficients de mortalités par pêche F/an. L’application du modèle prédictif de Tompson et Bell (1934) révèle un état d’exploitation élevé du rouget de vase dans la région d’étude. Le maximum de rendement soutenu du stock du rouget de vase dans la baie de Bou Ismail (MSY) est atteint à un facteur d’effort de 1.39 avec une valeur maximale de Y/R = 35.198g. Au-delà, le rendement reste constant pour chuter par la suite. Le traitement des données de la VPA (VIT4 WIN) renseigne sur un bon renouvellement annuel de la biomasse du stock de M. barbatus. Ce rapport est estimé à 193.11%. Toutefois, les résultats montrent que le niveau présent de l’effort de pêche est supérieur à celui qui correspond au MSY. Ceci indique que l’exploitation de ce stock a dépassé le niveau d’équilibre. Et par ailleurs, la production maximale économique équilibrée (MSE) est obtenue avec un facteur de F (FMSE = 0.6), renseigne sur un niveau présent de l’effort de pêche est supérieur au FMSE, ce qui dénote une surcapacité, même si les aspects économiques étudiés sur la pêcherie en question, concluent à des résultats positifs.
