68 results on '"Jarboui, O"'
Search Results
2. Predictive distribution models of European hake in the south-central Mediterranean Sea
- Author
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Garofalo, G., Fezzani, S., Gargano, F., Milisenda, G., Ben Abdallah, O., Ben Hadj Hamida, N., Jarboui, O., Chemmam-Abdelkader, B., Khoufi, W., Micallef, R., Mifsud, R., Gancitano, S., Rizzo, P., Zgozi, S., Ceriola, L., Arneri, E., and Fiorentino, F.
- Published
- 2018
- Full Text
- View/download PDF
3. Distribution, abundance and population structure of Hexaplex trunculus and Bolinus brandaris (Gastropoda: Muricidae) in offshore areas of the Gulf of Gabès, southern Tunisia
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Elhasni, K, Vasconcelos, P, Dhieb, K, El Lakhrach, H, Ghorbel, M, and Jarboui, O
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artisanal fisheries, bottom trawls, bycatch, fishery management, fishery yield, GIS mapping, stock assessment - Abstract
The banded murex Hexaplex trunculus and purple dye murex Bolinus brandaris are frequently caught as bycatch by bottom trawlers operating in the Gulf of Gabès, southern Tunisia. Although these muricid gastropods might importantly constitute an additional source of income for fishermen as well as help to diversify local shellfish production, information on their catches is relatively scarce. Hence, the present study aimed to assess the status of local populations of H. trunculus and B. brandaris, including data on their spatial and depth distributions, abundance, biomass, population structure and mortality. Fishing surveys using bottom trawls were performed between May 2006 and June 2007 in offshore areas of the Gulf of Gabès. In total, 198 fishing hauls were analysed, corresponding to a total fishing duration of 333.3 hours and a total prospecting area of 1 534 ha at depths of 20–86 m. Altogether, 3 026 H. trunculus and 3 599 B. brandaris of a broad size range (22.9−91.1 and 22.4−97.0 mm shell length, respectively) were sampled during the study period. GIS-produced maps were employed to determine the species’ spatial and bathymetric distributions by extrapolating their estimated fishing yield (bycatch per unit effort), abundance, biomass and mortality in relation to the total area surveyed in the gulf. The results provide valuable baseline information that may be applied to management proposals for regulating this untargeted resource, ultimately assisting sustainable exploitation and long-term preservation of this alternative fishing resource in the offshore areas of the Gulf of Gabès.Keywords: artisanal fisheries, bottom trawls, bycatch, fishery management, fishery yield, GIS mapping, stock assessment
- Published
- 2017
4. Genetic tools for management and conservation of the red coral populations [Corallium rubrum (Linnaeus, 1758)] of the North of Tunisia
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Jaziri S, Costantini F, Rugiu L, Abbiati M, Jarboui O, and Jaziri S, Costantini F, Rugiu L, Abbiati M, Jarboui O
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population genetic, conservation, management, harvesting, Mediterranean - Published
- 2015
5. Distribución y abundancia de los primeros estadios de desarrollo de Sardina pilchardus en el golfo de Túnez (Mediterráneo central) en relación con los factores ambientales
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Zarrad, R., Missaoui, H., F. (Francisco) Alemany, Hamza, A., Romdhane, M. S., García, A., Jarboui, O., and M Rabet, R.
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lcsh:SH1-691 ,spatial distribution ,huevos ,SH1-691 ,larvae ,spawning seasonality ,lcsh:Aquaculture. Fisheries. Angling ,eggs ,golfo de Túnez ,distribución espacial ,Aquaculture. Fisheries. Angling ,larvas ,Gulf of Tunis ,estacionalidad de la puesta ,Sardina pilchardus - Abstract
Four seasonal surveys were carried out in the Gulf of Tunis between summer 2002 and spring 2003 to study the abundance and distribution of Sardina pilchardus eggs and larvae in relation to environmental parameters. In the Gulf of Tunis, Sardina pilchardus begins spawning in autumn (23 eggs/10 m²) and attains its peak in winter (257 eggs/10 m²) when the mean SST is lowest (13.4°C). Sardine reproduction seems to be triggered by the decrease in the SST. In winter, the main spawning areas were located to the south of Zembra Island and the north of Cape Bon. Larvae were more abundant in winter (38 larvae/10 m²), while lower densities were collected in autumn and spring (1 larva/10 m²). The highest abundance of larvae (288 larvae/10 m²) was recorded southwest of Zembra Island. Eggs and larvae were mainly concentrated in the relatively warmer and saltier waters with high zooplankton abundance and, inversely, with a low concentration of nitrate and chlorophyll a and a low diatom abundance. Se llevaron a cabo cuatro campañas en el golfo de Túnez, entre verano del 2002 y primavera del 2003, con el objetivo de estudiar la abundancia y distribución de los huevos y larvas de Sardina pilchardus en relación con parámetros ambientales. En el golfo de Túnez Sardina pilchardus inicia la freza en otoño (23 huevos/10 m²), alcanzando el pico de puesta en invierno (257 huevos/10 m²), cuando la temperatura superficial media (SST) es mínima (13.4°C). La reproducción de la sardina se dispara al parecer por el descenso de la SST. En invierno, las principales áreas de puesta se localizaron al sur de la isla de Zembra y en el norte del Cabo Bon. Las larvas fueron más abundantes en invierno (38 larvas/10 m²); mientras que se recogieron menores densidades en otoño y primavera (1 larva/10 m²). La mayor abundancia larvaria (288 larvas/10 m²) fue observada en el suroeste de la isla de Zembra. Los huevos y larvas se concentraron principalmente en las aguas relativamente más cálidas y salinas, con altas abundancias de zooplancton, e inversamente bajas concentraciones de nitrato, clorofila a y abundancia de diatomeas.
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- 2008
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6. Predictive distribution models of European hake in the south-central Mediterranean Sea
- Author
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Garofalo, G., primary, Fezzani, S., additional, Gargano, F., additional, Milisenda, G., additional, Ben Abdallah, O., additional, Ben Hadj Hamida, N., additional, Jarboui, O., additional, Chemmam-Abdelkader, B., additional, Khoufi, W., additional, Micallef, R., additional, Mifsud, R., additional, Gancitano, S., additional, Rizzo, P., additional, Zgozi, S., additional, Ceriola, L., additional, Arneri, E., additional, and Fiorentino, F., additional
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- 2017
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7. Anchovy (Engraulis encrasicolus) early life stages in the Central Mediterranean Sea: connectivity issues emerging among adjacent sub-areas across the Strait of Sicily
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Patti, B., primary, Zarrad, R., additional, Jarboui, O., additional, Cuttitta, A., additional, Basilone, G., additional, Aronica, S., additional, Placenti, F., additional, Tranchida, G., additional, Armeri, G. M., additional, Buffa, G., additional, Ferreri, R., additional, Genovese, S., additional, Musco, M., additional, Traina, A., additional, Torri, M., additional, Mifsud, R., additional, and Mazzola, S., additional
- Published
- 2017
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8. Morphometric and Meristic Characters of Greater Amberjack Seriola dumerili (Pisces: Carangidae) from the Gulf of Gabes, Tunisia
- Author
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Sley, A., primary, Hajjej, G., additional, Jawad, Laith A., additional, Jarboui, O., additional, and Bouain, A., additional
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- 2016
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9. An ecosystem model of an exploited southern Mediterranean shelf region (Gulf of Gabes, Tunisia) and a comparison with other Mediterranean ecosystem model properties
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Hattab, T., Lasram, F. B. R., Albouy, C., Romdhane, M. S., Jarboui, O., Halouani, G., Cury, Philippe, and Le Loc'h, François
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Ecosystem approach to fisheries ,Ecosystem modeling ,Mediterranean Sea ,Food web ,Ecopath ,Trophic structure ,Gulf of Gabes - Abstract
In this paper, we describe an exploited continental shelf ecosystem (Gulf of Gabes) in the southern Mediterranean Sea using an Ecopath mass-balance model. This allowed us to determine the structure and functioning of this ecosystem and assess the impacts of fishing upon it. The model represents the average state of the ecosystem between 2000 and 2005. It includes 41 functional groups, which encompass the entire trophic spectrum from phytoplankton to higher trophic levels (e.g., fishes, birds, and mammals), and also considers the fishing activities in the area (five fleets). Model results highlight an important bentho-pelagic coupling in the system due to the links between plankton and benthic invertebrates through detritus. A comparison of this model with those developed for other continental shelf regions in the Mediterranean (i.e., the southern Catalan, the northern-central Adriatic, and the northern Aegean Seas) emphasizes similar patterns in their trophic functioning. Low and medium trophic levels (i.e., zooplanlcton, benthic molluscs, and polychaetes) and sharks were identified as playing key ecosystem roles and were classified as keystone groups. An analysis of ecosystem attributes indicated that the Gulf of Gabes is the least mature (i.e., in the earliest stages of ecosystem development) of the four ecosystems that were compared and it is suggested that this is due, at least in part, to the impacts of fishing. Bottom trawling was identified as having the widest-ranging impacts across the different functional groups and the largest impacts on some commercially-targeted demersal fish species. Several exploitation indices highlighted that the Gulf of Gabes ecosystem is highly exploited, a finding which is supported by stock assessment outcomes. This suggests that it is unlikely that the gulf can be fished at sustainable levels, a situation which is similar to other marine ecosystems in the Mediterranean Sea. Crown Copyright (c) 2013 Published by Elsevier B.V. All rights reserved.
- Published
- 2013
10. Methods of length frequency analysis were used to study the growth of the Spot-tail Mantis Shrimp, Squilla mantis (L., 1758), in the Tunisian water (Gulf of Tunis, Gulf of Gabes, and Gulf of Hammamet)
- Author
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Mili, S., Ennouri, R., Jarboui, O., and Missawi, H.
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Length ,Shrimp culture ,Growth - Abstract
Les distributions des tailles de la squille Squilla mantis (L., 1758) pêchée dans les eaux tunisiennes (golfes de Tunis, Hammamet et Gabès) ont été analysées par différentes méthodes pour étudier la croissance de ce crustacé. La décomposition modale des distributions de taille des captures de cette espèce a permis de calculer les paramètres de croissance L∞ (mm), K (an-1) et t0 de S. mantis en utilisant le modèle de Von Bertalanffy (1938). La fonction mathématique de Von Bertalanffy a permis de montrer que dans les trois golfes de la Tunisie, la croissance des femelles est inférieure à celle des mâles. Le taux de croissance est supérieur pour les squilles du golfe de Gabès par rapport à celui du golfe de Hammamet et du golfe de Tunis. La population totale est composée de 3 classes de taille (1 classe par an) avec une durée de vie maximale estimée à 3 ans. Different techniques have been used to separate the length frequency distributions to determinate the average length of the various cohorts. Growth parameters (L∞ (mm), K (an-1) and t0) were calculated using the growth model of Von Bertalanffy (1938) and the data of age and mean length. The mathematical function of Von Bertalanffy demonstrated that female growth is lower than males in the three Gulfs of Tunisia. The growth rate is higher for mantis shrimp captured in the Gulf of Gabes in comparison with the Gulf of Hammamet and Tunis. The population at sea consists of 3 year-classes and the life span is estimated at about 3 years. Key words: Spot-tail mantis shrimp, Squilla mantis, length frequency, Growth, Tunisian waters. Published Distributions des tailles Croissance Squilla mantis
- Published
- 2013
11. Comparative study between parameters of reproduction of two species of <Carangidae>: <Caranx crysos> and <Caranx rhonchus> of the gulf of Gabes
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Sley, A., Jarboui, O., and Bouain, A.
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Spawning seasons ,Reproduction - Abstract
Ce travail constitue une étude comparative entre les paramètres de reproduction de Caranx crysos et ceux de Caranx rhonchus du golfe de Gabès. Afin de déterminer la maturité sexuelle, le cycle sexuel et la période de ponte, les mensurations ont été relevées sur un échantillon de C. crysos composé de 1668 individus (95mm ≤ LT≤ 416 mm) et de 1313 individus de Caranx rhonchus (10mm≤LT≤306 mm). Il ressort de cette étude que Caranx rhonchus atteint sa maturité sexuelle (LT50% femelles = 182,09 mm et LT50% mâles = 182,2 mm) à une taille inférieure à celle estimée chez Caranx crysos (LT50% femelles = 259,79 mm et LT50% mâles = 245,88 mm). En outre, les variations mensuelles du Rapport Gonado-Somatique (RGS%), montre des cycles sexuels synchrones pour les mâles et les femelles pour les deux espèces étudiées. La période de reproduction s’étend de mars à septembre pour C. crysos et de mars à novembre chez C. rhonchus. La période de ponte de C. rhonchus (octobre-novembre) est plus prolongée qui celle chez C. crysos (Septembre). La maturation gonadique des deux espèces étudiées coïncide avec l’augmentation de la température dans le golfe de Gabès, la ponte a lieu avec la baisse de la température. This work constitutes a comparative study between reproductive parameters of Caranx crysos and those of Caranx rhonchus from the gulf of Gabes. To determine sexual maturity, sexual cycle and spawning periodicity, a total of 1668 specimens of Caranx crysos (95mm ≤ TL≤ 416 mm) and 1313 specimens of Caranx rhonchus (10mm≤TL≤306 mm) were collected. Caranx rhonchus occurred sexual maturity (TL50% females = 182,09 mm and TL50% males = 182,2 mm) before Caranx crysos (TL50% females = 259,79 mm and TL50% males = 245,88 mm). Monthly changes in the Gonado-Somatic Index (GSI%) showed that sexual cycles of males and females for two species are synchronous. Reproductive period was from March to September for Caranx crysos and from March to November for Caranx rhonchus. Spawning period of Caranx rhonchus (October-November) is more longer that Caranx crysos (September). Published Caranx crysos Caranx rhonchus Période de ponte Maturité sexuelle Cycle sexuel
- Published
- 2013
12. Anchovy (Engraulis encrasicolus) early life stages in the Central Mediterranean Sea: connectivity issues emerging among adjacent sub-areas across the Strait of Sicily.
- Author
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Patti, B., Zarrad, R., Jarboui, O., Cuttitta, A., Basilone, G., Aronica, S., Placenti, F., Tranchida, G., Armeri, G. M., Buffa, G., Ferreri, R., Genovese, S., Musco, M., Traina, A., Torri, M., Mifsud, R., and Mazzola, S.
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ENGRAULIS encrasicolus ,SPAWNING ,FISH eggs ,FISH populations - Abstract
The combined use of field data on anchovy (Engraulis encrasicolus, Linnaeus, 1758) egg distribution in the Central Mediterranean Sea on both sides of the Strait of Sicily (Sicilian-Maltese and Tunisian waters) and Lagrangian simulations were used to assess the pattern of connectivity between these two sub-areas as a result of spawning activity. The field data were collected during ichthyoplankton surveys carried out in summer 2008 and 2010. The simulation runs showed considerable (up to 20%) rates of particle exchange in both directions (from Tunisian to Sicilian-Maltese waters and vice versa). However, considering the typical high mortality rates of anchovy early stages, the actual larval exchange rates across the Sicily Strait are supposed to be significantly lower (<1%), supporting the hypothesis that the anchovy population sub-units in the Strait of Sicily can be considered as separate fish stocks for the evaluation of their optimum exploitation rates. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
13. Comparative study of the biometric characters in the pearl oyster Pinctada radiata from the Gulf of Gabes (Tunisia)
- Author
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Derbali, A., Jarboui, O., and Ghorbel, M.
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Biometrics ,Pearl oysters - Abstract
Le présent travail porte sur l’étude des caractères biométriques de l’huître perlière Pinctada radiata des îles de Kerkennah pour la différenciation entre les populations des deux sites El Kraten et El Jorf à partir d’un pouvoir discriminant des caractères métriques et méristiques. Durant l’année 2007, un total de 2360 et 2422 individus ont été collectés respectivement dans les sites d’El Kraten et d’El Jorf. Les résultats des comparaisons des moyennes et des variances des caractères biométriques à l’aide du test "F" de Fisher et du test "t" de Student plaident en faveur d’une discrimination entre les deux populations. De même, les résultats des analyses multivariées (l’Analyse en Composante Principale (ACP) et l’Analyse Factorielle Discriminante (AFD)) confirment l’hétérogénéité des deux groupes. Les résultats obtenus semblent être liés aux conditions environnementales et écologiques des deux secteurs d’étude. The variability of morphological characters and sexual maturity of the invasive pearl oyster Pinctada radiata were investigated within populations from Kerkennah islands using discriminant tests. During 2007, a total of 2360 and 2422 individuals were collected from sites El Kraten and El Jorf, respectively. The comparison of the averages and the variances of the biometric characters using the Fisher test "F" and the Student test "t" revealed an important inter-population morphological variability between Kerkennah Island populations. Both multidimensional methods (Principal Components Analysis (ACP) and Discriminating Factor Analysis (AFD)), highlighted the high divergence between P. radiata populations. This finding could be related to the environmental and ecological conditions of the two bathymetric sites. Published Morphological characters Pinctada radiata
- Published
- 2012
14. Spatial distribution and abundance of the Stomatopoda and Decapoda crustaceans sampled by bottom trawl in the gulf of Gabes (Tunisia, Central Mediterranean)
- Author
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El Lakhrach, H., Hattour, A., Jarboui, O., Elhasn, K., Alfonso Ramos Espla, Biología Marina, and Universidad de Alicante. Departamento de Ciencias del Mar y Biología Aplicada
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Crustacean communities ,Sediment ,Zoología ,Bottom characteristics ,Abiotic factors - Abstract
Stomatopoda and Decapoda crustaceans play an important role in the marine ecosystems through varied ecological strategies and bio-disturbance of species' community with an important effect on the benthic communities' structure, in addition to abiotic factors (such as temperature, salinity and type of bottom). Furthermore, faunal inventories are necessary, especially when focused on ecological and economical important groups, such as the Malacostraca class, and concentrated on areas under intense fishery activity such as the gulf of Gabes (Central Mediterranean). Inshore and offshore collections were performed at 30 sites of the Gulf's continental shell (20-260 m depth) in spring 2009, by employing two experimental bottom trawl gears. Overall, 40 species were detected in the samples distributed among Stomatopoda (only one species) and Decapoda (7 Dendrobranchiata, 3 Caridea, 1 Astacidea, 7 Anomura, and 21 Brachyura). In terms of abundance, Stomatopoda contributed for about 14%. The coastal area of the gulf (especially, areas in the North-east of Gabès and North-west of Djerba between 20 and 40 m depth) hosted a high variety of species; the most abundant were Squilla mantis, Paguristes eremite, Inachus dorsettensis and the exotic intruder Trachysalambria palaestinensis. This work was undertaken within the framework of research activities in the “Marine Living Resources” laboratory of the National Institute of Marine Sciences and Technologies (INSTM), financed by the Tunisian Ministry of Agriculture and Fisheries.
- Published
- 2012
15. Engraulis encrasicolus (Linnaeus, 1758)egg and larval distribution in the eastern coast of Tunisia in relation to environmental characteristics
- Author
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Zarrad, R., García, A., F. (Francisco) Alemany, and Jarboui, O.
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Centro Oceanográfico de Baleares ,Engraulis encrasicolus ,eggs ,distribution ,larvae ,Pesquerías ,east Tunisia - Abstract
An ichthyoplankton survey was conducted on the eastern coast of Tunisia from the 10th to 18th August 2004 with the investigation of 68 stations. The sampling period corresponded to stratified summer conditions, with average SST 26.97°C. The thermocline was found between 25 and 50 m depth. The eastern coast of Tunisia was influenced by the water exchanges between the eastern and western Mediterranean. Anchovy eggs and larvae were a major component of the ichthyoplankton, representing 26 and 19% of the total mean fish egg and larval abundances, respectively. Their mean abundances were 108 eggs.10 m-2 and 112 larvae.10 m-2. The spawning areas were mainly located off the 100 m isobaths, with the maximum abundance occurring near the shelf break, as opposed to the inshore waters where anchovy eggs and larvae were practically absent. Depth was the main factor controlling the distribution of anchovy eggs and larvae. Larval transport from the spawning areas is made evident following southward to south-eastward directions, Sí
- Published
- 2012
16. Comparative characterization of the spawning environments of European anchovy, Engraulis encrasicolus, and round sardinella, Sardinella aurita (Actinopterygii: Clupeiformes) in the eastern coast of Tunisia
- Author
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Zarrad, R., Alemany, F., Jarboui, O., Garcia, A., and Akrout, F.
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anchovy ,round sardinella ,spawning environments ,Ionian Sea - Abstract
Background. The distribution of early ontogenic stages of small pelagic fishes is important for understanding the dynamics of their fluctuating populations. To fill a gap in the knowledge we conducted a comparative analysis on the distribution of eggs and larvae of the exploited populations of European anchovy, Engraulis encrasicolus (L.) and round sardinella, Sardinella aurita (Valanciennes, 1847), in the eastern coast of Tunisia. Materials and methods. A multidisciplinary survey was carried out in the summer of 2008, from June 23 through July 9. Samples were taken over a grid of 71 stations. Temperature and salinity profiles were recorded at each station by CTD casts and water samples were taken by means of a Rosette equipped with Niskin bottles. Ichthyoplankton was sampled by oblique tows with a Bongo net of 60 cm mouth diameter and 335-µm mesh nets. To specify the preferred spawning environment the quotient values were estimated for each variable. Results. The eggs and larvae of both species represented an important proportion of the ichthyoplankton, around 50% for each ontogenic stage. Anchovy mainly spawned in the shelf edge, north-east of Kuriate Island, with a minor spawning area near Cap Bon and Kelibia. The main spawning area of the round sardinella was in the warmer waters. It was located near the major spawning ground of anchovy. Anchovy eggs were scarce in the coastal zones and in the south of the study area, whereas round sardinella eggs were scarce in the north. The main spawning grounds of anchovy coincided with the area of higher zooplankton abundance while round sardinella spawning grounds correspond with those areas of highest chlorophyll-a and zooplankton. This distribution suggests a propensity for food availability, for both adults and larvae, as the location of spawning grounds of these species. Conclusion. Both anchovy and sardinella spawned mainly in deeper waters within the limits of the continental shelf. Each species appeared to have a specific strategy for spawning that was influenced by physical and biological variables.
- Published
- 2012
17. Analysis of the mitochondrial DNA Cytochrome b gene in Octopus vulgaris (Cephalopoda, Octopoda) from Tunisian northern and southern coasts
- Author
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Nafkfa, Ch., Ezzeddine, S., Chemmam, B., Jarboui, O., and Fadlaoui-Zid, K.
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Octopus ,Genetics ,Octopus fisheries - Abstract
Le poulpe commun Octopus vulgaris représente, parmi les céphalopodes, la principale espèce exploitée par la pêche côtière surtout dans la région Sud de la Tunisie. Une analyse génétique basée sur l’approche moléculaire et de population est jugée nécessaire pour assurer une gestion crédible et durable du stock. L’analyse a porté sur le polymorphisme de l’ADN mitochondrial par séquençage d’un fragment du gène cytochrome b de taille 485pb chez 52 échantillons collectés dans deux localités différentes : îles de Galite (Nord) et Elketf –Zarzis (Sud). Les résultats obtenus montrent que sur les 52 séquences réalisées, il y’a 14 haplotypes différents dont deux partagés entre les deux localités. L’haplotype le plus représenté est rencontré chez 29 individus. Une différenciation génétique entre les deux lots a été mise en évidence (FST = 0.055 ; P
- Published
- 2012
18. Annual reproductive cycle, spawning periodicity and sexual maturity of false scad Caranx rhonchus (Geoffroy Saint-Hilaire, 1817) (Pisces, Carangidae) from the South-Eastern Mediterranean (Gulf of Gabès, Tunisia)
- Author
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Sley, A., primary, Hadj Taeib, A., additional, Jarboui, O., additional, Ghorbel, M., additional, and Bouain, A., additional
- Published
- 2015
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19. Cycle de reproduction et inversion du sexe chez Pagellus erythrinus dans le golfe de Tunis
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Zarrad, R., Cherif, M., Gharbi, H., Jarboui, O., and Missaoui, H.
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Reproduction ,Sea bream fisheries ,Sexual maturity - Abstract
Dans ce travail, nous étudions le cycle sexuel et l’inversion sexuelle du pageot commun Pagellus erythrinus dans le golfe de Tunis. De février 2003 à janvier 2004, un total de 807 individus ont été échantillonnés mensuellement à partir des opérations de chalutage benthique. La longueur totale varie de 7,6 à 28,5 cm. L’espèce a été caractérisée par un hermaphrodisme protérogyne. Le sex-ratio (femelles / mâles) a été de 2,78. La saison de ponte s’étend d’avril à octobre et principalement de mai à juillet. Cette dernière est liée à l’élévation de la température des eaux de surface qui passe de 16 à 24°C. La première maturité sexuelle (L50) se situe chez les femelles à une longueur totale de 14,6 cm et chez les mâles à 15,8 cm. L’inversion du sexe a pris place à des longueurs comprises entre 17 et 18 cm. The reproductive biology of the common pandora Pagellus erythrinus was investigated in the Gulf of Tunis. A total of 807 specimens were collected by bottom trawl on a monthly basis between February 2003 and January 2004. Total length ranged from 7.6 to 28.5 cm. The species was characterized by protogynous hermaphroditism. The overall females-to-males sex-ratio was 2.78. The reproductive season extended from April to October and mainly from May to July as the SST ranged between 16 to 24°C. First maturity (L50) was reached at 14.6 cm total length for females and 15.8 cm for males. The sex reversal took place between 17 and 18 cm. لدراسة تكاثر سمك المرجان الأحمر Pagellus erythrinus بخليج تونس، تم جمع 807 سمكة خلال الفترة الممتدة من فيفري 2003 إلى جانفي 2004 من خلال عمليات الصيد بالجر القاعي. تتراوح الأطوال الجملية بين 7,6 و 28,5 صم. تميز هذا النوع ب hermaphrodisme protérogyne. قدر عامل إناث / ذكور ب2,78 . ويتغير الجنس بين 17 و 18 صم. يمتد موسم التكاثر من شهر أفريل إلى أكتوبر وأساسا من ماي إلى جويلية. وارتبط ذلك بارتفاع درجة حرارة مياه سطح البحر من 16 إلى 24 درجة. قدر الطول عند أول نضج جنسي ب 14,6 صم بالنسبة للإناث و15,8 صم بالنسبة للذكور. Published Pagellus erythrinus, reproduction, première maturité sexuelle, inversion de sexe.
- Published
- 2010
20. First occurrence of the yellow roughneck shrimp, Rimapenaeus similis (Smith, 1885) (Crustacea: Decapoda: Penaeidae) in the Mediterranean Sea (Tunisian waters)
- Author
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Hamida-Ben Abdallah, OB, Hamida, NB, Jarboui, O, and Froglia, C
- Published
- 2010
21. التوزيع الجنسي و علاقة الوزن و الطول و عامل الظروف للتن بونقشة بالسواحل التونسية
- Author
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Hajjej, G., Hattour, A., Allaya, H., Jarboui, O., and Bouain, A.
- Subjects
Tuna fisheries ,Length-weight relationships ,Sex ratio - Abstract
Cette étude, présente des informations sur le sex-ratio, la relation taille-masse et le coefficient de condition de la thonine commune Euthynnus alletteratus (Rafinesque, 1810) collectée à divers endroits des côtes tunisiennes entre janvier 2008 et septembre 2009. Le nombre total des individus collectés était de 536. La longueur à la fourche était comprise entre 19,2 et 97,8cm. Les résultats obtenus montrent que le sex-ratio est significativement en faveur des femelles et varie également avec la taille. Une allométrie négative a été établie pour les mâles ainsi que pour les femelles. Les valeurs calculées du coefficient de condition chez Euthynnus alletteratus sont 1,606 pour les femelles et 1,587 pour les mâles. The study is an attempt to estimate sex-ratio, length-weight relationship and condition factor of little tunny Euthynnus alletteratus collected from Tunisian waters. A total of 536 specimens of Euthynnus alletteraus were collected from January 2008 to September 2009. The fork length is ranged between 19,2 and 97,8 cm. The females significantly outnumber the males and the sex-ratio varies according to the length. The growth in length is faster than in weight for males and females. The condition factor computed for female Euthynnus alletteratus was 1,606, while for the male was 1,587. تحتوي هذه الدراسة على نتائج المعطيات الخاصة بالتن بونقشة التي تم تجميعها من كامل السواحل التونسية في الفترة الممتدة بين جانفي 2008 و سبتمبر 2009. كان العدد الجملي للعينات التي وقع فحصها 536 و يتراوح طول الأسماك بين 19,2 و 97,8 صم. تبين من خلال التوزيع الجنسي للأفراد أن نسبة الإناث تفوق نسبة الذكور بفارق هام و أن هذا التوزيع يتأثر بالطول. كذالك تبين من خلال دراسة مختلف العلاقات القائمة بين الوزن و الطول أن نسبة نمو الذكور و الإناث في الطول أهم من نموها في الوزن. من ناحية أخرى تبين أن عامل الظروف لهذه الأسماك كان كالتالي: 1,606 بالنسبة للإناث و 1,587 بالنسبة للذكور Published sex-ratio, relation taille-masse, coefficient de condition, Euthynnus alletteratus
- Published
- 2009
22. النظام الغذائي لأسماك التريلية الحمراء المتواجدة بالمياه الشمالية للبلاد التونسية
- Author
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Gharbi, H., Cherif, M., Jarboui, O., and Missaoui, H
- Subjects
Mullus surmuletus ,Prey selection ,Feeding behaviour ,Diets ,Feeding habits - Abstract
L’étude du régime alimentaire du rouget de roche (Mullus surmuletus L, 1758) des côtes Nord tunisiennes durant l’année 2006 fait apparaître que ce mullidae euryphage se nourrit de la macrofaune benthique principalement de crustacés (amphipodes et décapodes), de polychètes et de mollusques. D’autres proies comme les échinodermes, les nématodes et les alevins de poissons sont pris accessoirement. Le régime alimentaire de cette espèce varie avec les saisons et la taille de poisson mais aucune influence de la sexualité n’a été démontrée. إن دراسة محتويات أمعاء سمك التريلية الحمراء المتواجدة بالسواحل الشمالية للبلاد التونسية مكنت من التعرف كمّا و كيفا على نوع غذائها المتمثل خاصة في القشريات٬الحيوانات الشائكة و الرخويات بدرجة أولى و الديدان الخيطية و يرق الأسماك بدرجة ثانية. كذلك اتضح من خلال هذا البحث٬ أن النظام الغذائي لهذه الأسماك يختلف كمّا و كيفا حسب الطول و الفصول في حين لم نلحظ أي تغيير يذكر حسب الجنس. The study of the feeding habits of the striped red mullet (Mullus surmuletus L, 1758) of the Tunisian North coasts during the year 2006 fact of appearing that this mullidae euryphage consumed benthic macrofaune mainly shellfish, polycheata and molluscs. Of another preys like echinodermata, the nematoda and the finfish constitute its secondary preys. The diet of this species varies with the seasons and the body size but any influence of sexuality was not shown. Published
- Published
- 2008
23. Preliminary results on spatial distribution of abundance indices, nursery and spawning areas of Merluccius merluccius and Mullus barbatus in the central Mediterranean
- Author
-
GAROFALO G., BEL HASSEN M., JARBOUI O., ZGOZI S., GRISTINA M., FIORENTINO, RAGONESE S., and CAMILLERI M.
- Subjects
Fishery resources ,nursery grounds ,spawning grounds ,stock identification ,geographical distribution ,subpopulation - Abstract
Preliminary results on spatial distribution of some key variables (abundance indices, recruits and spawner density indices) of Merluccius merluccius and Mullus barbatus populations in central Mediterranean are presented at regional level for the first time. Data were collected during trawl surveys carried out under national programmes (Italy, Libya, Malta and Tunisia) in the MedSudMed Project area (GFCM GSAs 12, 13, 14, 15, 16 and 21). An effort to standardize the data collection and processing was made with the support of the MedSudMed Project. About 290 hauls were made within the depth range 10-800 m in May-August 2003, covering an area of about 150,000 km2. For each haul, spawners were identified as female fish whose total length was greater than the length at 50% maturity (the established common value of 30 cm TL and 15 cm TL for hake and red mullet, respectively). Also for each haul, the proportion of recruits, expressed in terms of young of the year, was estimated by analysis of the length-frequency distribution. In the case of hake, a species that reaches maturity at the age of one year, the spatial distribution of the young fish with a length lower than L50% (juveniles) was also considered. Spawning and nursery areas were identified as areas showing the highest values of spawner and recruit indices, respectively. To avoid bias due to the different sampling gears, all the indices were standardized to the maximum value, keeping separate the areas sampled with different nets. Qualitative comparison of hake and red mullet stocks among the Italian-Maltese, the Tunisian and the Libyan sub-regions, revealed that large differences exist in abundance indices and the demographic structure implicit in these indices. Though differences in the small size-classes may result from differences in gear selectivity and survey season, the contrasting distribution observed in the large size-classes is likely to result from an actual paucity of large specimens in the Italian-Maltese sub-region. Analysis of spatial distribution by life-phase showed that both species are distributed, or migrate, across the boundary of two adjacent GSAs or the boundary of a zone of national maritime jurisdiction and the adjacent high seas. Proposals for future research were made to better understand occurrence of stock units and the effect of environmental factors on them.
- Published
- 2008
24. Biometric characters of the spottail mantis shrimp Squilla mantis in Tunisian coasts
- Author
-
Mili, S., Jarboui, O., and Missaoui, H.
- Subjects
Comparative studies ,Squilla mantis ,Biometrics ,Population dynamics ,Statistical analysis ,Population structure - Abstract
Pour l’étude biométrique de la squille Squilla mantis, un échantillonnage régulier a été réalisé dans le golfe de Tunis, le golfe de Hammamet et le golfe de Gabès de janvier 2005 à décembre 2006. Les équations morphométriques de la squille, dans le golfe de Gabès, ont montré que la croissance relative du telson, celle de la masse totale et celle de la masse éviscérée par rapport à celle du céphalothorax sont caractérisées par une allométrie positive. Par contre, la longueur totale croît négativement par rapport à celle du céphalothorax. Pour le golfe de Hammamet, ces caractères ont une croissance marquée par une allométrie négative à part la masse éviscérée. Les équations morphométriques de la squille du golfe de Tunis ont montré une allométrie positive pour les masses, une allométrie négative pour la taille totale et une isométrie pour le telson. L’application du test d’égalité des coefficients de régression pour les mâles et les femelles du golfe de Hammamet a permis d’accepter l’hypothèse du parallélisme des droites de régression pour les différentes relations exceptée celle de la taille totale en fonction de la masse éviscérée. Pour le golfe de Tunis et le golfe de Gabès, seule la relation longueur du telson en fonction de la longueur céphalothoracique est similaire chez les deux sexes. Par ailleurs, l’application des tests de Bartlett et de Student a montrée qu’il existe une différence significative entre les trois populations étudiées. تمّ جمع عيّنات من الشيقالي بصفة منتظمة من خليج تونس وخليج الحمامات وخليج قابس خلال الفترة المتراوحة بين جانفي 2005 وديسمبر 2006. بيّنت المعادلات أن النموّ النسبي للسمات المورفومتريّة للشيقالي بكل من خليج تونس و خليج قابس إيجابي مقارنة بطول الرأسصدر ،أمّا بالنسبة لخليج الحمامات فإن النمو سلبي لأغلب السمات. مكّنت مقارنة المعادلات الخطيّة لمختلف المعطيات الشكليّة من تبيين وجود ازدواج لكلى الجنسين خاصة بخليج الحمامات. كما بينت الاختبارات وجود اختلافات في النّمو النسبي للشيقالي بين الخلجان الثلاثة A regular sampling was carried out along the Tunisian coasts (Gulf of Tunis, Gulf of Hammamet and Gulf of Gabes) from January 2005 to December 2006 in order to study the biometric characters of the spottail mantis shrimp Squilla mantis. The morphometric equations for this species in the Gulf of Gabes showed that the relative growth in size of telson and total weight compared to the cephalotorax length was characterised by a positive allometry; However, the total size relative growth is negative. For the Gulf of Hammamet, the equations showed a negative allometry except that of the weight. The morphometric equations of S. mantis in the Gulf of Tunis showed a positive allometry for the weights and a negative one for the total size. The allometry is isometric for the telson. The application of equality test between linear regression coefficient for males and females in the Gulf of Hammamet showed that the hypothesis of parallelism hypothesis can be accepted for all the relations except those of the total size according to the weight. For the Gulf of Tunis and the Gulf of Gabes only the relation telson-cephalotorax length is similar at the two sexes. The application of the Bartlett-test and Student-test showed that there is a significant difference between the three populations in this study. Published
- Published
- 2008
25. le rouget de roche (mullus surmuletus l. 1758) des cotes nord tunisiennes : reproduction, sexualite et croissance
- Author
-
M’rabet, R, Gharbi, H, Missaoui, H, Cherif, M., and Jarboui, O
- Subjects
Mullus surmuletus ,Spawning ,Length-weight relationships ,Sexual maturity ,Growth ,Size distribution ,Sex ratio ,Biological surveys - Abstract
L’objectif principal de ce travail, est la réactualisation des paramètres biologiques du rouget de roches des côtes Nord tunisiennes qui sont indispensables pour toute étude ultérieure d’évaluation de stock. Le suivi mensuel du rapport gonado-somatique a montré que la période de ponte de rouget de roche s’étale sur 3 mois d’avril à juillet. La taille pour laquelle 50% des individus sont matures a été estimée à une longueur totale de 16,43cm pour les femelles et de 16,02cm pour les mâles. L’étude de la sex-ratio en fonction des mois a montré que les femelles sont toujours plus nombreuses que les mâles. La répartition des sexes en fonction de la longueur totale montre que les femelles dominent dans la plupart des classes de taille. Les équations d’allométries montrent que chez Mullus surmuletus, la croissance pondérale en fonction de la longueur totale de l’animal apparaît isométrique chez les mâles et les femelles alors qu’elle est affectée par une allométrie majorante pour les deux sexes réunies. The aim of this work is to update biological parameters of the striped red mullet in the northern Tunisian coasts, which would be compulsory for ulterior evaluation stocks studies. The monthly variation of gonadosomatic index indicate that striped red mullet is spawning from April to July. Length frequency distribution showed that females where more abundant in the majority of size classes. The estimated lengths at maturity (Lm50) were 16.02cm for males and 16.43cm for females. According to the length-weight relationship; allometry is isometric for both males and females but positive for pooled sexes. : تهدف هذه الدراسة إلى تحيين المعطيات البيولوجية الخاصة بأسماك التريلية الحمراء المتواجدة بالسواحل الشمالية للبلاد التونسية و التي تعتبر جد ضرورية لحسن التصرف في المخزون. أفضت المتابعة الشهرية لوزن الغدد التناسلية بالنسبة لوزن الجسم أن فترة التكاثر تمتد على مدى ثلاثة أشهر ابتداء من شهر أفريل حتى بداية شهر جويلية٬ من ناحية أخرى تبين أن الطول القياسي لهذه الأسماك عند بلوغ أول نضج جنسي كان كالتالي: 16.02 صم بالنسبة للذكور و 16.43 صم بالنسبة للإناث. كما استنتجنا من خلال التوزيع الجنسي للأفراد أن النسبة المئوية للإناث تفوق بكثير نسبة الذكور طيلة فصول السنة كما أنه تبين أن الأحجام الكبيرة كانت جلها متكونة من الإناث. أخيرا تبين من خلال دراسة مختلف العلاقات القائمة بين الوزن و الطول أن نسبة النمو كانت متوازية عند الإناث و الذكور كل على حدة في حين كانت جد ايجابية عند جميع الأفراد من الجنسين. Published
- Published
- 2007
26. Stocks assessment of shelfishes and cartography of their geographical distribution in the coastal area of Zarzis
- Author
-
Ben Abdallah, O., Ben Hadj Hamida, N., and Jarboui, O.
- Subjects
Cartography ,Stock assessment ,Biomass ,Marine crustaceans ,Geographical distribution ,Shellfish - Abstract
The experimental survey done, in august 2005, in coastal marine zone (0 - 20 m) of Zarzis showed the existence of numerous species of shellfishes of which Tricolia speciosa, Smaragdia viridis, Nassarius incrassatus, Cerithium vulgatum and Gibbulla umbilicaris are the most important gasteropods and, Pinctada radiate and Donax trunculus the main bivalves. The biomasses estimation, based on the method of swept area, in the studied zone showed that P. radiate is the most abundant species with about 20 000 tones, followed by C. vulgatum (7 645 tones) and T. speciosa (more than 1 000 tones). The Donax trunculus biomass is very low with only 13 tones. Finally, the abundance indexes distribution cartography permitted us to note that it varies from one species to another one and from one sampled station to another. Les prospections expérimentales effectuées, au mois d’août 2005, au niveau de la partie marine côtière (0 - 20 m) de la région de Zarzis, ont montré l’existence d’un nombre considérable d’espèces de mollusques (bivalves, gastéropodes) dont les plus abondantes sont Tricolia speciosa, Smaragdia viridis, Nassarius incrassatus, Cerithium vulgatum et Gibbulla umbilicaris pour les gastéropodes et, Pinctada radiata et Donax trunculus pour les bivalves. Par ailleurs, par l’estimation des biomasses, basée sur la méthode de l’aire balayée, au niveau de la zone d’étude, nous avons remarqué que la pintadine P. radiata est l’espèce la plus abondante avec environ 20 000 tonnes, suivie de C. vulgatum avec plus de 7 645 tonnes et T. speciosa avec plus de 1 000 tonnes. Le haricot de mer Donax trunculus est présent avec une biomasse très faible ne dépassant pas les 13 tonnes. Enfin, la cartographie de la répartition des indices d’abondance des ces espèces a montré que leur répartition varie d’une espèce à l’autre et d’une station de prélèvement à l’autre. بينت العمليات الاستكشافية التي قمنا بها خلال شهر أوت 2005 في المنطقة البحرية الساحلية بجهة جرجيس، وجود أنواع عديدة من القوقعيات أهمها Tricolia speciosa, Smaragdia viridis, Nassarius incrassatus, Cerithium vulgatum و Gibbulla umbilicarisبالنسبة إلى معديات الأرجل و Pinctada radiata و Donax trunculus بالنسبة للانواع ذات الصدفتين. كما أظهرت عملية تقييم المخزون أن Pinctada radiata يمثل أهم نوع حيث بلغ مخزونه 000 20 ألف طن، يليه Cerithium vulgatum بـ 645 7 طن وأخيرا Tricolia speciosa الذي يتجاوز مخزونه ألف طن بقليل. أما اللوبية Donax trunculus فقد بينت النتائج أنه متواجد بقلة حيث لا يتجاوز مخزونه 13 طن. أخيرا ومن خلال رسم خرائط التوزيع الجغرافي لدلائل الكثرة التابعة لأهم الأنواع المتواجدة، لاحظنا أنها تختلف من نوع إلى آخر ومن منطقة إلى أخرى. Published
- Published
- 2006
27. حول ظهور القمبري Metapenaeus stebbingi في خليج قابس
- Author
-
Ben Hadj Hamida-Ben Abdallah, O., Ben Hadj Hamida, N., Jarboui, O., and Missaoui, H.
- Subjects
New records ,Marine crustaceans ,Metapenaeus stebbingi ,Geographical distribution - Abstract
Nous signalons pour la première fois, dans cette note, la présence de la crevette faucon Metapenaeus stebbingi en Tunisie. Cette espèce, qui fait partie des crevettes lesseptiennes introduites à travers le canal de Suez, a été observée au niveau de deux échantillons de crevette mouchetée Metapenaeus monoceros débarqués à Sfax (Sud-Est de la Tunisie). We record for the first time in this note, the presence of the peregrine shrimp Metapenaeus stebbingi in Tunisia. This lesseptian species was observed in two samples of the speckled shrimp Metapenaeus monoceros landed in Sfax port (Southern East of Tunisia). نشير من خلال هذا العمل لأوّل ظهور للقمبري Metapenaeus stebbingi في خليج قابس. وقد تمّ وجود هذا النوع في عيّنات للقمبري الأبيضMetapenaeus monoceros الذي تمّ شراؤه من السّوق البلدية لبيع الأسماك بصفاقس. Published
- Published
- 2006
28. First record of the Veneridae Ruditapes philippinarum in the north part of Gabes gulf
- Author
-
Chouba, L., Zamouri-Langar, N., Jarboui, O., and Mrabet, R.
- Subjects
New records ,Ruditapes philippinarum ,Marine molluscs ,Geographical distribution - Abstract
Dans cette étude nous signalons la présence d’une espèce d’origine indo-pacifique, Ruditapes philippinarum, sur les côtes tunisiennes, dans le golfe de Gabès. Les échantillons prélevés ont montré des pourcentages de 89 pour l’espèce indigène Ruditapes decussatus et 11 pour l’espèce exotique Rudiapes philippinarum à Gargour (au sud de Sfax); alors que ces pourcentages sont respectivement de 21,5 et de 78,5 au nord de cette région, à El Aouabed. In this study we notified in Gabes gulf (Tunisian coasts), the presence of an indo-pacific origin specie Ruditapes philippinarum. The samples showed 89 % for the indigenous species Ruditapes decussatus and 11 % for the exotic species Ruditapes philippinarum in Gargour (south of Sfax); whereas these percentages are respectively from 21.5 % and 78.5 % to the north of this region, in El Aouabed. في ﺇطار برنامج تقييم القوقعيات التي لها قيمة اقتصادية بالسواحل التونسية، وقع العثور في شمال خليج قابس على صنف من القفالة ﺃصيلة المحيط الهادي و الهندي والمعروف باسمRuditapes philippinarum . بينت العينات المتأتية من منطقتي قرقور والعوابد (ولاية صفاقس) ﺃن نسبة هذا الصنف يصل ﺇلى 11 بالمائة بمنطقة قرقور و 78,5 بالمائة بمنطقة العوابد، بينما كانت النسب المأوية لصنف القفالة المعروفة ب Ruditapes decussatus تصل الى 89 بالمائة بالمنطقة الاولى و 21,5 بالمائة بالمنطقة الثانية. Published
- Published
- 2006
29. Monthly variability of zooplankton and ichthyoplankton in the Gulf of Tunis
- Author
-
Missaoui, H., El Abed, A., M'rabet, R., Romdhane, M.S., Zarrad, R., and Jarboui, O.
- Subjects
Temporal variations ,Ichthyoplankton ,Community composition ,Fish larvae ,Zooplankton - Abstract
Monthly variability of zooplankton and ichthyoplankton abundance and composition were studied in 6 stations in the Gulf of Tunis between February 2003 and January 2004. Plankton trawls were horizontal, in surface and at night. Study area seems to be influenced by climatic conditions and the outflow of Majreda River that affect the surface temperature and salinity. Copepods, with many abundance peaks in the year, formed the most abundant group (84%) followed by cladocerans (8%) and chaetognaths (3%). The appendicularians, cladocerans and medusae had swarms in the summer, the creseis and the chaetognths in the autun and the zoae larvae in the spring. The highest fish spawning periods was in summer then the highest larva abundance was in winter and summer.Original Abstract: De Fevrier 2003 a Janvier 2004, douze campagnes mensuelles ont ete effectuees dans 6 stations dans le golfe de Tunis pour l'etude du zooplancton et de l'ichtyoplancton. Les traits ont ete horizontaux et pendant la nuit. La zone d'etude semble etre tres influencee par le climat de la region et des apports de l'Oued Majreda qui affectent la temperature et la salinite des eaux de surface. Les copepodes, avec plusieurs pics pendant l'annee, ont ete le groupe le plus dominant du zooplancton soit 84% puis les cladoceres (8%) et les chaetognathes (3%). Les appendiculaires, les cladoceres et les meduses ont eu des essaims estivaux, les creseis et les chaetognathes automnaux alors que pour les larves zoes printanieres. L'intensite de ponte des poissons a ete la plus forte pendant l'ete alors que les larves ont ete les plus abondantes pendant l'hiver et l'ete. Published
- Published
- 2004
30. Exploitation, growth and sex-ratio of speckled shrimp in Gabes gulf (Tunisia)
- Author
-
Jarboui, O., Ben Abdallah, O., Missaoui, H., and Ben Hadj Hamida, N.
- Subjects
MED, Tunisia, Gabes Gulf ,Espèces exotiques ,Crevettes ,Introduced species ,Metapenaeus monoceros ,Growth ,Exploitation ,Marine crustaceans ,Croissance ,Shrimps ,Sex ratio - Abstract
Les crevettes, particulièrement Penaeus kerathurus, sont considérées parmi les espèces de crustacés les plus exploitées au niveau des côtes tunisiennes, essentiellement dans le golfe de Gabès. Depuis l’année 1993, une nouvelle espèce de crevette d’origine lesseptienne est apparue dans le golfe et s’est bien adaptée avec ses conditions climatiques et environnementales : c’est la crevette blanche Metapenaeus monoceros. L’objectif principal de cette étude consiste à suivre l’exploitation de cette espèce dans la région du golfe de Gabès, à étudier sa croissance relative et à déterminer la composition des captures selon le sexe. D’après les résultats obtenus nous avons pu constater que, durant la dernière décennie, la production de cette espèce dans le golfe de Gabès était irrégulière. L’étude biométrique effectuée a révélé que ses croissances linéaire et pondérale relatives varient de la même façon ; alors que le sex-ratio a été nettement en faveur des femelles. تعتبر القشريات و خاصة القمبري الملكي Penaeus kerathurus من أهم الكائنات البحرية التي يتم استغلالها بالمياه التونسية و خاصة بمنطقة خليج قابس. منذ سنة 1993 ظهر بالخليج نوع جديد من القشريات وهو القمبري الأبيض Metapenaeus monoceros, أصيل البحر الأحمر والذي تأقلم، شيئا فشيئا، مع المعطيات المناخية والبيئية للخليج. يتمثل الهدف الرئيسي من هذه الدراسة في متابعة استغلال هذا النوع من القشريات ومحاولة جمع بعض المعطيات البيولوجية عنه وخاصة تلك التي تهم تركيبته الجنسية ونموه النسبي. هذا وقد بينت النتائج المتحصل عليها أن إنتاج القمبري الأبيض خلال العشرية الأخيرة قد تميز بعدم الإستقرارية. كما بينت أن النمو النسبي حسب الطول والوزن يتطوران بنفس الطريقة لدى هذا النوع من القمبري وأن نسبة الإناث تفوق بوضوح نسبة الذكور. The shrimp, particularly the caramote prawn Penaeus kerathurus, are the most crustacean species exploited in the gulf of Gabes. Since 1993, the speckled shrimp Metapaeus monoceros, a lesseptian specie, appeared in this area and became well adapted to its climatic and environmental conditions. The main objective of this study is to follow the exploitation patterns of this species, to study his relative growth and to estimate the catch composition regard sex. The obtained results show an irregular catch variation in Gabes gulf. From the biometric study carried out, we can deduce that the speckled shrimp relative growth in length and weight are similar. In other hand, the sex-ratio is in favour of females. Published
- Published
- 2003
31. Diet of Symphodus (Crenilabrus) ocellatus off the Tunisian Southern coasts
- Author
-
Bouain, A., Ouannes-Ghorbel, A., Jarboui, O., and M’rabet, R.
- Subjects
Crustacés ,Food organisms ,Labridae ,Mollusques ,Prey selection ,Symphodus ocellatus ,Régime alimentaire ,MED, Tunisia, South coast ,Diets ,Zoobenthos ,Shellfish - Abstract
Symphodus (Crenilabrus) ocellatus of the Tunisian southern Gabes coasts feeds on the small bentic invertebrates of shallow medowe bed. The preferential preys of this Labridae fish are crustaceans and mollusces. Trophic variations of this fish by seasons show its specific adaptive response to changes in environment. يرتكز النظام الغذائي لسمك الخضير Symphodus (Crenilabrus) ocellatus على الكائنات القاعية البحرية الصغيرة الحجم والمتواجدة على البساط العشبي القليل العمق فهو يتكون أساسا من القوقعيات (معديات الأرجل الصغيرة) والقشريات الصغيرة. إختلاف نوعية الغذاء حسب فصول السنة تبين لنا مدى تأقلم هذا النوع من السمك مع تغير محيطه. Le régime alimentaire de Symphodus (Crenilabrus) ocellatus des côtes sud de la Tunisie est constitué de petits invertébrés benthiques des herbiers peu profonds. Les proies préférentielles de ce poisson labridé sont les crustacés et les mollusques. Le spectre alimentaire de ce poisson varie d’une saison à l’autre ce qui montre que ce crénilabre peut s’adapter aux changements du milieu. Published
- Published
- 2003
32. Fish biomass assessment in freshwater using echo prospection : Application to the Sidi Salem reservoir
- Author
-
Cadic, N., Kraiem, M.M., Proteau, J.P., El Abed, A., Djemali, I., and Jarboui, O.
- Subjects
Freshwater fish ,Retenue du barrage de Sidi Salem, Tunisie ,Echo prospection ,Stock assessment ,Echo surveys ,Evaluation des stocks ,Water reservoirs ,Dams - Abstract
L’évaluation de stock dans les plans d’eaux douces en Tunisie par écho prospection constitue une première. La retenue du barrage de Sidi Salem a été choisie comme site pilote afin de mettre au point la méthodologie. L’étude du comportement piscicole dans la retenue a permis de favoriser le comptage de cibles individuelles à l’écho intégration. L’écho prospection a permis d’évaluer la biomasse instantanée toutes espèces confondues dans la retenue du barrage de Sidi Salem à 192,4 t, soit des biomasses respectives pour le sandre, le mulet, le silure, la carpe, le gardon et le rotengle de 75 t, 7,7 t, 1,9 t, 3,9 t, 11,5 t et 92,3 t. تهتم هذه الدراسة بتقييم الثروة السمكية بالمياه العذبة التونسية بالذبذبات الصوتية. فقد تم تعديل هذه الطريقة لأول مرة في سد سيدي سالم، مما مكننا من تعداد الأسماك بصفة فردية بفضل دراسة تنقلاتها. يقدر المخزون الحالي من جميع أنواع الأسماك في مياه سد سيدي سالم بحوالي 192,4 طنا موزعة كما يلي: الصندر 75 طنا والبوري 7,7 طنا والقط 1,9 طنا والكارب 3,9 طنا والشبوكة البرتقالية 11,5 طنا والشبوكة الحمراء 92,3 طنا. The stock assessment in the Tunisian freshwater by hydro acoustic is original. The reserve of the Sidi Salem dam was selected as an experimental area in order to develop the methodology. The study of the piscicultural behaviour of the fish species in the reserve made it possible to support the counting of individual targets to the echo integration. The echo prospection allows us to assess the instantaneous biomass of all the species of the Sidi Salem reservoir at 192.4 t, that’s to say biomass for pikeperch, mullet, wels, carp, roach and rudd at 75 t, 7.7 t, 1.9 t, 3.9 t, 11.5 t and 92.3 t respectively. Published
- Published
- 2003
33. تعددية وسائل الصيد في مصيدة خليج قابس
- Author
-
El Abed, A., Jabeur, Ch., Missaoui, H., Gobert, R., and Jarboui, O.
- Subjects
ACP ,PCA ,Cluster analysis ,Fishery technology ,Fishing gear ,Fishing vessels ,Trawlers ,Classification hiérarchique ,Chalutiers ,Typologie ,Marine fisheries ,Flottille ,Fleet - Abstract
Le golfe de Gabès est une pêcherie plurispécifique exploitée par plusieurs engins de pêche. Environ 75 % des chalutiers du pays opèrent dans cette zone. Les apports de la pêche au chalut (chalut de fond type crevettier et chalut de fond type méditerranéen) sont très diversifiés. Une analyse multivariée (Analyse en Composante Principale ACP suivie d'une classification ascendante hiérarchique) réalisée sur les captures des marées des chalutiers travaillant dans cette région a permis d'identifier onze (11) types d'activités: deux métiers pour les crustacés, deux métiers pour les céphalopodes, trois métiers pour la pêche des poissons, deux métiers regroupant la crevette, la seiche et les poissons et finalement deux métiers péchant les «divers». Ces métiers sont caractérisés aussi bien par leur composition spécifique que par leur saisonnalité. امتازت مصيدة خليج قابس بنوعية الأسماك و تعددية وسائل الصيد. مراكب الصيد بالكركارة الموجودة في هذه الجهة تمثـل 75 بالمائـة مـن مجموعها بالجمهورية التونسية. إنتاج الصيد بالكركارة متنوع جدا بالرغم من استعمالـه لوسيلتـي صيد فقط، الكركارة القاعية الخاصة بصيد القمبري و الكركارة القاعية المتوسطية. الطريقة التحليلية متعددة المتغيرات التي طبقناها على معطيات الإنتاج حسب الأنواع المصطادة و حسب خرجـات و وحـدة الصيد بالكركارة في هـذه المنطقـة، مكنتنا من تقسيم الأنشطة إلى 11 نوعـا: مهنتين لصيد القشريات، مهنتين لصيد رأسيات الأرجل،3 لصيد الأسمـاك، نوعان أدمجا صيد القشريات و الحبار و الأسماك في آن واحد و أخيرا مهنتين لصيد أنواع ذات قيمة تجارية ضعيفة. هذه الأنشطـة مميزة بتركيبتها النوعيــة و بمواسمهــــا. Gabes gulf ( South-Est of Tunisia) is a multi-species and multi-gears fishery area. About 75 % of the Tunisian Trawlers number frequent this area. Productions of the trawl fishing are diversified although only 2 types of gears are used ; shrimp trawl and Mediterranean a trawl (trawl with high vertical opening). A multivariable analysis (PCA and cluster analysis) carried out using one year data identified 11 trawling activities : Two(2) select crustacean, two(2) others catches both shrimp, cuttlefish and fish, two(2) specified in the catch of cephalopods, three (3) are oriented to the exploitation of fish and, finally two(2) activities exploited other species that having less commercial value. These "métiers" are characterized by their typical composition and seasonality. Published Techniques de pêche ; Flottille ; Chalutier
- Published
- 2000
34. Reproductive biology of the Golden grey mullet Liza aurata, in the Gulf of Gabes (central Mediterranean, Tunisia) in the Gulf of Gabes (central Mediterranean, Tunisia)
- Author
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ABDALLAH, C., primary, GHORBEL, M., additional, and JARBOUI, O., additional
- Published
- 2013
- Full Text
- View/download PDF
35. Reproductive biology of the annular seabream, Diplodus annularis (Linnaeus, 1758), in the Gulf of Gabes (Central Mediterranean)
- Author
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Chaouch, H., primary, Hamida-Ben Abdallah, O., additional, Ghorbel, M., additional, and Jarboui, O., additional
- Published
- 2013
- Full Text
- View/download PDF
36. Reproductive cycle of Bolinus brandaris (Gastropoda: Muricidae) in the Gulf of Gabès (southern Tunisia)
- Author
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ELHASNI, K., primary, VASCONCELOS, P., additional, GHORBEL, M., additional, and JARBOUI, O., additional
- Published
- 2013
- Full Text
- View/download PDF
37. Annual reproductive cycle, spawning periodicity and sexual maturity of blue runnerCaranx crysos(Pisces, Carangidae) from the Gulf of Gabes (Tunisia, Eastern Mediterranean)
- Author
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Sley, A., primary, Jarboui, O., additional, Ghorbel, M., additional, and Bouain, A., additional
- Published
- 2012
- Full Text
- View/download PDF
38. Reproductive biology of the rock goby, Gobius paganellus (Actinopterygii: Perciformes: Gobiidae), on the southern Tunisian coast (Gulf of Gabes)
- Author
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Hajji, F, primary, Ouannes-Ghorbel, A, additional, Ghorbel, M, additional, and Jarboui, O, additional
- Published
- 2012
- Full Text
- View/download PDF
39. Spatial distribution and abundance of the megabenthic fauna community in Gabes gulf (Tunisia, eastern Mediterranean Sea)
- Author
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EL LAKHRACH, H., primary, HATTOUR, A., additional, JARBOUI, O., additional, ELHASNI, K., additional, and RAMOS-ESPLA, A.A., additional
- Published
- 2012
- Full Text
- View/download PDF
40. Biometry, Length-length and Length-weight Relationships of Little Tuna Euthynnus alletteratus in the Tunisian Waters
- Author
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Hajjej, G., primary, Hattour, A., additional, Hajjej, A., additional, Allaya, H., additional, Jarboui, O., additional, and Bouain, A., additional
- Published
- 2011
- Full Text
- View/download PDF
41. Contribution to the study of the reproductive cycle of the wide-eyed flounder Bothus podas podas in the Gulf of Gabès (Tunisia)
- Author
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Abid, S., primary, Ouannes-Ghorbel, A., additional, Jarboui, O., additional, and Bouain, A., additional
- Published
- 2010
- Full Text
- View/download PDF
42. Reproductive biology of the cockle Cerastoderma glaucum (Mollusca: Bivalvia)
- Author
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Derbali, A, primary, Jarboui, O, additional, and Ghorbel, M, additional
- Published
- 2009
- Full Text
- View/download PDF
43. La biologie et la dynamique de la population de la limande (Limanda limanda, L.) dans la partie sud de la mer du Nord = Biologie en populatiedynamica van de (Limanda limanda, L.) in de zuidelijke Noordzee
- Author
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Jarboui, O.
- Subjects
Abundance ,Spawning ,Research vessels ,Limanda limanda (Linnaeus, 1758) [Dab] ,Biomass ,Growth ,Distribution ,Mortality ,Sex ratio ,ANE, France, North Sea - Published
- 1992
44. Annual reproductive cycle, spawning periodicity and sexual maturity of blue runner Caranx crysos ( Pisces, Carangidae) from the Gulf of Gabes ( Tunisia, Eastern Mediterranean).
- Author
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Sley, A., Jarboui, O., Ghorbel, M., and Bouain, A.
- Subjects
- *
CARANX , *FISH spawning , *CARANGIDAE , *FISH sex ratio , *GAMETOGENESIS - Abstract
From June 2004 to May 2006, the reproductive biology of the blue runner Caranx crysos was studied in the Gulf of Gabes ( Southern Tunisia). Of 1668 individuals examined, 777 were females (46.6%) and 891 were males (53.4%). The sex ratio significantly deviated in favour of males (♀:♂ = 0.87 : 1). The difference in the numbers of females and males was significant among size-classes. However, there was no significant difference between sexes over months and seasons. Monthly changes in the Gonado- Somatic Index ( GSI) showed a rapid increase during summer to very high levels in July (3.51% for males and 2.55% for females) and August (3.47% for males and 2.59% for females) before declining sharply in September (0.58% for females and 0.38% for males). The gametogenesis activity began with a pre-maturation phase, from 20 May to the first 10 days of July, followed by a pre-spawning phase, from 20 July to 20 August. From the last 10 days of August to 20 September the gonads were in the ripe and spawning stages. From the end of September to early May, gonads were in the post-spawning and resting stages. The size at which 50% of the population reached sexual maturity was significantly different in males and females: males attained sexual maturity at fork length FL50 = 210.20, whereas females attained maturity at FL50 = 222.3 mm. Age at maturity was 2.4 years for males and 2.8 years for females. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
45. Seascape connectivity of European anchovy in the Central Mediterranean Sea revealed by weighted Lagrangian backtracking and bio-energetic modelling
- Author
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Rafik Zarrad, Rosalia Santoleri, Othman Jarboui, Federico Falcini, Hechmi Missaoui, Maria Cristina Mangano, Luigi Palatella, Bernardo Patti, Angela Cuttitta, Antonio Di Cintio, Raffaele Corrado, Guglielmo Lacorata, Marco Torri, Gianluca Sarà, Falcini F., Corrado R., Torri M., Mangano M.C., Zarrad R., Di Cintio A., Palatella L., Jarboui O., Missaoui H., Cuttitta A., Patti B., Santoleri R., Sara' G., and Lacorata G.
- Subjects
0106 biological sciences ,Mediterranean climate ,Marine conservation ,Settore BIO/07 - Ecologia ,010504 meteorology & atmospheric sciences ,Climate ,Ecological connectivity ,Population Dynamics ,Fisheries ,lcsh:Medicine ,Distribution (economics) ,Environment ,01 natural sciences ,Models, Biological ,Article ,Mediterranean sea ,Lagrangian back-trajectories ,European anchovy ,Mediterranean Sea ,Animals ,Ecosystem ,lcsh:Science ,0105 earth and related environmental sciences ,Seascape ,Multidisciplinary ,geography.geographical_feature_category ,biology ,business.industry ,Physical oceanography ,010604 marine biology & hydrobiology ,lcsh:R ,Fishes ,biology.organism_classification ,Fishery ,Strait of Sicily ,Geography ,Larva ,lcsh:Q ,business ,Channel (geography) - Abstract
Ecological connectivity is one of the most important processes that shape marine populations and ecosystems, determining their distribution, persistence, and productivity. Here we use the synergy of Lagrangian back-trajectories, otolith-derived ages of larvae, and satellite-based chlorophyll-a to identify spawning areas of European anchovy from ichthyoplanktonic data, collected in the Strait of Sicily (Central Mediterranean Sea), i.e., the crucial channel in between the European and African continents. We obtain new evidence of ecosystem connectivity between North Africa and recruitment regions off the southern European coasts. We assess this result by using bio-energetic modeling, which predicts species-specific responses to environmental changes by producing quantitative information on functional traits. Our work gives support to a collaborative and harmonized use of Geographical Sub-Areas, currently identified by the General Fisheries Commission for the Mediterranean. It also confirms the need to incorporate climate and environmental variability effects into future marine resources management plans, strategies, and directives.
- Published
- 2020
46. Predictive distribution models of European hake in the south-central Mediterranean Sea
- Author
-
S. Zgozi, O. Ben Hadj Hamida-Ben Abdallah, S. Fezzani, N. Ben Hadj Hamida, Germana Garofalo, F. Fiorentino, Reno Micallef, Francesco Gargano, R. Mifsud, P. Rizzo, W. Khoufi, Luca Ceriola, Enrico Arneri, Giacomo Milisenda, B. Chemmam-Abdelkader, Othman Jarboui, S. Gancitano, Garofalo, G., Fezzani, S., Gargano, F., Milisenda, G., Ben Abdallah, O., Ben Hadj Hamida, N., Jarboui, O., Chemmam-Abdelkader, B., Khoufi, W., Micallef, R., Mifsud, R., Gancitano, S., Rizzo, P., Zgozi, S., Ceriola, L., Arneri, E., and Fiorentino, F.
- Subjects
0106 biological sciences ,Mediterranean climate ,Generalized additive model ,Aquatic Science ,Spatial distribution ,010603 evolutionary biology ,01 natural sciences ,Generalized additive models ,Seafloor geophysical feature ,Mediterranean sea ,Hake ,Seafloor geophysical features ,Merluccius merluccius ,Species distribution modelling ,14. Life underwater ,Large adults habitat ,Settore MAT/07 - Fisica Matematica ,biology ,010604 marine biology & hydrobiology ,biology.organism_classification ,Recruits habitat ,Environmental niche modelling ,Fishery ,Strait of Sicily ,Geography ,Merluccius merlucciu ,Predictive modelling - Abstract
The effective management and conservation of fishery resources requires knowledge of their spatial distribution and notably of their critical life history stages. Predictive modelling of the European hake (Merluccius merluccius L., 1758) distribution was developed in the south-central Mediterranean Sea by means of historical fisheries-independent databases available in the region. The study area included the international waters of the south-central Mediterranean Sea and the territorial waters of Italy, Malta, Tunisia and Libya. Distribution maps of predicted population abundance index, and probabilistic occurrence of recruits and large adults were obtained by means of generalized additive models using depth and seafloor characteristics as predictors. Presence/absence data of the two life stages was obtained using threshold values applied to the mean weight of the survey catches. Modelling results largely matched previously reported knowledge on habitat preference of the species and its critical life phases. Hake recruits showed an occurrence peak at 200 m depth with preference for soft bottoms. Large adults preferred deeper and harder bottom substrates. Prediction maps allowed to improve our knowledge on the distributional patterns of one of the most important shared stocks in the south-central Mediterranean. This knowledge is essential for an appropriate development of regional-spatial-based management plans.
- Published
- 2018
47. Can Ultrasound Reliably Detect Complicated Appendicitis in Pediatric Patients?
- Author
-
Zouari M, Belhajmansour M, Jarboui O, Ben Kraiem N, and Ben Dhaou M
- Published
- 2024
- Full Text
- View/download PDF
48. Features Associated with Delayed Diagnosis of Appendicitis in Children: A Retrospective Analysis of 1411 Cases.
- Author
-
Zouari M, Belhajmansour M, Jarboui O, Ben Kraiem N, and Mhiri R
- Published
- 2024
- Full Text
- View/download PDF
49. Seascape connectivity of European anchovy in the Central Mediterranean Sea revealed by weighted Lagrangian backtracking and bio-energetic modelling.
- Author
-
Falcini F, Corrado R, Torri M, Mangano MC, Zarrad R, Di Cintio A, Palatella L, Jarboui O, Missaoui H, Cuttitta A, Patti B, Santoleri R, Sarà G, and Lacorata G
- Subjects
- Animals, Climate, Ecosystem, Environment, Fishes growth & development, Larva growth & development, Mediterranean Sea, Population Dynamics, Fishes physiology, Models, Biological
- Abstract
Ecological connectivity is one of the most important processes that shape marine populations and ecosystems, determining their distribution, persistence, and productivity. Here we use the synergy of Lagrangian back-trajectories, otolith-derived ages of larvae, and satellite-based chlorophyll-a to identify spawning areas of European anchovy from ichthyoplanktonic data, collected in the Strait of Sicily (Central Mediterranean Sea), i.e., the crucial channel in between the European and African continents. We obtain new evidence of ecosystem connectivity between North Africa and recruitment regions off the southern European coasts. We assess this result by using bio-energetic modeling, which predicts species-specific responses to environmental changes by producing quantitative information on functional traits. Our work gives support to a collaborative and harmonized use of Geographical Sub-Areas, currently identified by the General Fisheries Commission for the Mediterranean. It also confirms the need to incorporate climate and environmental variability effects into future marine resources management plans, strategies, and directives.
- Published
- 2020
- Full Text
- View/download PDF
50. Genetic structure of Octopus vulgaris (Cephalopoda, Octopodidae) in the central Mediterranean Sea inferred from the mitochondrial COIII gene.
- Author
-
Fadhlaoui-Zid K, Knittweis L, Aurelle D, Nafkha C, Ezzeddine S, Fiorentino F, Ghmati H, Ceriola L, Jarboui O, and Maltagliati F
- Subjects
- Algorithms, Analysis of Variance, Animals, DNA biosynthesis, DNA genetics, DNA, Mitochondrial genetics, Demography, Gene Flow, Genetic Variation, Mediterranean Sea, Molecular Biology, Phylogeny, Polymerase Chain Reaction, Electron Transport Complex IV genetics, Mitochondria enzymology, Mitochondria genetics, Octopodiformes enzymology, Octopodiformes genetics
- Abstract
The polymorphism of the mitochondrial gene cytochrome oxidase III was studied in the Mediterranean octopus, Octopus vulgaris Cuvier, 1797. A total of 202 specimens from seven sampling sites were analysed with the aim of elucidating patterns of genetic structure in the central Mediterranean Sea and to give an insight into the phylogeny of the Octopus genus. Phylogenetic analyses showed that individuals from the central Mediterranean belong to the O. vulgaris species whose limits should nevertheless be clarified. Concerning genetic structure, two high-frequency haplotypes were present in all locations. The overall genetic divergence (Φ(ST)=0.05, P<0.05) indicated a significant genetic structuring in the study area and an AMOVA highlighted a significant break between western and eastern Mediterranean basins (Φ(CT)=0.094, P<0.05). Possible explanations for the observed patterns of genetic structuring are discussed with reference to their relevance for fisheries management., (Copyright © 2012. Published by Elsevier SAS.)
- Published
- 2012
- Full Text
- View/download PDF
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