Résumé: In this study, a multi-biomarker approach is applied to evaluate the biological responses of the black sea urchin Arbacia lixula along the west coast of Algeria. Sea urchins were sampled from six different Algerian West coast sites during two periods (February and August 2018). A series of biomarkers were monitored in the gonads: a glutathione-s-transferase enzyme involved in the phase II biotransformation process, Acetylcholinesterase as a biomarker of neurotoxicity, malondialdehydes as a biomarker of oxidative stress damage, metallothionein, a specific biomarker of metal stress, and Catalase as a biomarker of general stress. The data shows a significant effect of the period factor on the biomarker’s responses of A. lixula. The cold period seems to have a more marked influence on the variation of biomarkers, such as acetylcholinesterase inhibition, increased glutathione-s-transferase and catalase activity, and significantly elevated levels of metallothionein in contrast to malondialdehyde, whose levels are elevated in the hot period. Biomarker responses differed between sites depending on the degree of disturbance. Using the multi-biomarker pollution index allowed us to specify the state of health of each site, respecting a gradient of five pollution levels. The results indicate that site S4 is considered the most polluted, while site S3, the presumed reference site, appears to be the cleanest. The gonads of this species can be considered a reliable indicator of environmental stress and capable of establishing an integrated diagnosis of the state of the coastal ecosystem

Résumé: The reproduction, growth, mortality and exploitation of the caramot prawn, Penaeus kerathurus (Forskål 1775) are discussed for the first time on east Algerian coasts. Between December 2017 and January 2019, a total of 534 specimens including 254 females and 280 males were sampled from the gulf of Annaba. The reproduction season for this species extended from April to July. Macroscopically, five stages of ovarian maturation were determined, and mature ovaries were mainly observed between May and July. Length at first maturity was based on the presence of a spermatophore (TL50F = 172 mm) or 59 mm of cephalothoracic lengths (LC50F). Von Bertalanffy's growth parameters were determined for the total population, males and females. Natural mortality (M) was estimated according to Pauly (1980) and Djabali et al. (1994) calculation methods. The exploitation rate (E) was less than the 0.5 in both sexes. According to this result, we conclude that P. kerathurus stock was underexploited in the Gulf of Annaba.

Résumé: On the North African coast, data on the biology and ecology of the European eel Anguilla anguilla (L., 1758) are very sparse, despite the economic and ecological status of this species. This study aims to collect basic on the fractions of the populations that colonize two transitional waters in eastern Algeria. We provide here the first information on the composition and variations of the diet of A. Anguilla in Mellah lagoon (ML) and Wadi El Kebir (WEK). During one year (December 2008-November 2009), a total of 1120 eels (NML = 625; 24.3 < TL < 75.8 cm; 23 < TW < 842 g; NWEK = 495; 23.5 < TL < 83 cm; 23 < TW < 1470 g), was sampled. Qualitative and quantitative variations of the diet are looked for in the two sites according to season and development stages. The annual mean values of the coefficient of digestive vacuity were respectively 38.1% and 53.1%. This coefficient varies according to season and development stages. Anguilla anguilla is opportunistic and diversifies its diet between molluscs, teleost fish and Macrophyta, with a preference for crustaceans in the two ecosystems (%IRIML = 89.98%, IRIWEK = 96.15).

Résumé: In the last couple of years, a “Sponge Watch” Programme was launched in the Gulf of Annaba (North-eastern Algeria) with a goal of involving for the first time the sponges as bioindicators of heavy metals contamination in the biomonitoring programmes of the Algerian coasts. This study aimed to investigate the potential of a sponge’s species (Chondrilla nucula Schmidt, 1862) in the assessment of trace metal elements in the Gulf. In this context, the seasonal variation in the concentration of four trace metals (Cupper, Zinc, Lead and Cadmium) was monitored in C. nucula from two different areas during a one-year period in 2017-2018. Furthermore, a complementary approach based on the analysis of three oxidative stress biomarkers (glutathione, glutathione S-transferase, and malondialdehyde) was performed on the same samples to better characterize the biological response of the sponge to this kind of environmental stress. Similar environmental conditions in both sites of the Gulf were detected. The highest concentrations of the studied elements were recorded in the humid season (winter and spring), while the lowest were in the dry season (late summer to autumn). Otherwise, significant (P ≤ 0.05) variations were recorded in the accumulation of all metals, with the exception of lead, which seemed regulated at a certain level. On the other hand, the sponge’s biochemical parameters showed significant temporal fluctuation and seemed to follow those of metals. Therefore, the sponge C. nucula seems to be a suitable sentinel species to be considered in the biomonitoring programmes although it shows less tolerance to lead.

Résumé: The level of trace metal elements (TME) (Cd, Pd, Cu, Zn, Fe) was determined according to the seasons and the sexes in the muscle and the eggs of the deep-water pandalid shrimp Plesionika edwardsii (Brandt in Reise in den aussersten Norden und Osten Sibiriens wahrend der Jahre 1843 und 1844 mit allerhochster Genehmigung auf Veranstaltung der Kaiserlichen Akademie der Wissenschaften zu St. Petersburgausgefuhrt und in Verbindung mit vielen Gelehrten herausgegeben 2(1):77–148, 1851) of the east coast of Algeria. Using the inductively coupled atomic plasma emission spectrometry method (ICP AES), the distribution of trace metals shows a significant fluctuation according to the seasons and the sex. Throughout the annual sampling, the order of heavy metal concentrations in female and male muscle, as well as in eggs were Cd < Cu < Fe < Zn < Pb, Cd < Cu < Zn < Pb < Fe, Cd < Cu < Fe < Zn < Pb respectively. In this work the heavy metal concentrations in target tissues are below the permissible limits set by the international standard except for Pb, mainly in summer, autumn and spring, exhibiting alarming levels.

Résumé: This study is a contribution to the knowledge of the biology and population structure of an invasive American blue crab Callinectes sapidus Rathbun, 1896 (Decapoda: Brachyura: Portunidae). A total of 525 individuals, represented by 312 females (38.9 < CLf < 80.3 mm, 77 < WTf < 173 g) and 213 males (43.7 < CLm < 90.5, 80 < WTm < 175 g) was sampled between February 2021 and February 2022. The following parameters were determined: size structure, sex ratio, reproductive period, size at first sexual maturity, relationship between size and weight. The overall sex ratio was in favour of females (SR = 0.68, ² = 18.66). This dominance was maintained during all seasons, with the exception of Summer when the two sexes were numerically balanced. The first ovigerous females appeared in May and became the majority in July (63.8%). The size frequency distribution (LC) highlighted 5 different cohorts, which would correspond to ages 1 to 5, with respectively 4.4 cm, 5.5 cm, 6.8 cm, 7.8 cm, 8.3 cm of carapace length (CL). The CL / total body weight (TP) relationship resulted for both sexes: W = 4.82 CL -163.7 (r2 = 0.493). Females reach their first sexual maturity at 7.05 cm.

Résumé: This study addresses for the first time the biology of the comber, Serranus cabrilla (Linnaeus, 1758), from the eastern Algerian coast. From October 2015 to September 2016, 1063 specimens were collected each month in the Gulf of Annaba. The total length of the whole population ranged from 11.3 to 23.7 cm, and the population aged between 1 and 6 years old. The growth parameters obtained by von Bertalanffy model were: L∞ = 24.03 cm, k = 0.22 year–1 and t0 = –1.67 year for males, L∞ = 24.7 cm, k = 0.21 year–1 and t0 = –1.65 year for females and L∞ = 24.91 cm, k = 0.20 year–1 and t0 = –1.81 year for all individuals, with a growth performance (φ’) equal to 2.10 for both sexes and 2.09 for all specimens. The relationship between total length and body mass of fish for males, females, immatures and all individuals were EW = 0.013 TL3.01, EW = 0.008 TL3.05, EW = 0.015 TL2.82 and EW = 0.01 TL2.998, espectively. The sex-ratio was estimated at 0.49:1 in favor of females and the breeding season extended from March to July. Males and females reached their first sexual maturity at 16.08 and 16.37 cm TL, respectively

Résumé: In the framework of the biomonitoring programme of the Gulf of Annaba (north-eastern Algeria), this study aims to assess the health status of the Gulf by transplanting the brown mussel Perna perna (Linnaeus 1758) for 12 weeks (June 2017-August 2017) at three sites. The concentrations of copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd) and as well as a battery of enzymatic and non-enzymatic biomarkers were measured in mussels before and after the transplantation period. Furthermore, analysis of trace metals was performed on the surface layer of the sediment of all the sites. A significant increase in the Cu and Pb concentrations in the mussel dry tissues was observed after the transplantation period and followed the order of metal contamination of the surface layer sediments, indicating a relationship between the bioaccumulation of metals and their bioavailability at each site. Unlike those of Cu and Pb, Cd and Zn concentrations did not reach significant levels of bioaccumulation at any of the three study sites. The biomarker response results were complementary to the measured metal concentrations in the mussel tissues and were associated with the metal accumulation index. Metal bioaccumulation in mussels and supporting biomarker response results identified the most important pollution point sources in the area.

Résumé: The invasive sally lightfoot crab Percnon gibbesi (H. Milne Edwards, 1853) has spread among the coasts of the Mediterranean Sea, including the coasts of Annaba Gulf (Algeria). Investigating the trophic position of the species and looking for the seasonal variations in the diet of this alien decapod was the aim of this study. To do this, samples of P. gibbesi were collected along Annaba coasts within a year. The traditional stomach content analysis (SCA) was integrated to the stable isotope analysis (SIA) of nitrogen and carbon to provide a comprehensive evaluation of the feeding ecology of P. gibbesi, and its within-year variability. Results highlighted, for the first time, significant seasonal variation in P. gibbesi diet, improving our understanding of its trophic plasticity and potential dietary overlaps with other herbivore species. Its feeding plasticity is an asset in the successful expansion of its distribution. Relating its diet composition through the different seasons with the interactions with native herbivores will be essential to fully appreciate the impact of the spread of P. gibbesi in the Mediterranean Sea.

Résumé: The diet of the black scorpionfish Scorpaena porcus (linnaeus, 1758) of annaba Gulf (eastern Algeria) was studied from April 2011 to April 2012. A total of 520 specimens, with a total length between 10.2 and 27.8 cm, were analyzed. Analysis of the digestive contents revealed a dominance of decapods crustaceans (%IRI = 91.2). This species ingested an average of 0.58 prey weighing 0.73 g. For both sexes, arthropods were essential prey (%irim = 73.6; %irif = 86.9). The diet of large (L) individuals was mainly divided between arthropods (%iril = 56.3) and teleosts (%iril = 34). Small (S) and medium-sized (M) black scorpionfish mainly focused on arthropods (%iriS = 98.3; %irim = 86.5). The average annual digestive vacuity was of 40.8% and varied significantly according to seasons. There was no significant seasonal change in diet except in the summer.

Résumé: This study describes for the first time the presence of the subtropical crab Percnon gibbesi (H. Milne Edwards, 1853) on east Algerian coasts. The morphology was studied on 102 individuals (10.2 ≤ length of carapace ≤ 41.05 mm) sampled from Cap de Garde (West of the Gulf of Annaba). The crabs were sampled by free diving (< 2 m), between October 2015 and March 2016. The morphology was characterized using 16 metric descriptors and five meristic descriptors (number of spines on the anterior margin of the five pairs of pereiopods). The different parts of the body were expressed as a function of the length and width of the carapace. Measurements on the left and right chela were based on the length and width of the left and right chela. Possible variations of these dimensions were sought using linear regression with the method of the least rectangle (reduced major axis). The mean numbers, modes and extreme values of each meristic descriptor were calculated and the means were statistically compared between the two sides of the crabs.

Résumé: L’étude présentée ici tente de répondre à un besoin d’informations sur la diversité des gastéropodes en général et sur les Trochidae en particulier le long des côtes de l’est de l’Algérie. Un intérêt majeur est accordé à l’espèce Phorcus(=Osilinus ) turbinatus, en particulier à quelques aspects de son écologie et de sa biologie. Nous avons déterminé par la méthode indirecte de Battacharya en utilisant le logiciel FISAT II les différentes sous populations de P. turbinatus Dans les trois sites, les valeurs observées et théoriques de la croissance linéaire absolue et pondérale sont très proches ce qui indique une bonne description de la croissance par le modèle de Von Bertalanffy. La croissance relative est globalement minorante pour P. turbinatus de Rizi Amor et le site Mollo. Elle est isométrique à oued El Ganem, pour les mâles et les femelles. L’analyse statistique (ANOVA, MANOVA) a montré que la croissance relative des paramètres biométriques est influencée probablement par la pollution domestique du milieu.

Résumé: This study was carried out to describe the feeding habits of the comber Serranus cabrilla from the eastern coast of Algeria. Between October 2015 and September 2016, we examined a total of 831 individuals (11.3 < TL < 23.2 cm, 19.96 < TW < 157.7 g). Qualitative and quantitative composition of the diet have been analysed according to seasons, size, sex and sexual maturity: digestive vacuity (%VI), index of relative importance (%IRI) and trophic level (TROPH). The average annual digestive vacuity was of 18.05%. It varied over the year, with a maximum during spring and summer (reproduction period). Qualitative analysis revealed a total of 1959 preys for a total weight of 131.66 g, which corresponds to an average number (AN) and weight (AW) of about 2.88 and 0.19 g respectively. This species preferentially feeds on benthic preys, especially Crustacea (% IRI = 48.53) and teleost (% IRI = 29.14). The statistical comparison using the Spearman rank coefficient (rho) showed no significant differences in diet according to fishing seasons, sex or sexual maturity. Serranus cabrilla is a carnivorous predator (TROPH = 3.9; Se = 0.63; OI = 0.79) with a preference for decapod crustaceans and teleosts.

Résumé: The diet of the striped seabream Lithognathus mormyrus (Linnaeus, 1758) was investigated in the Gulf of Annaba (Eastern coast of Algeria). A total of 522 individuals (8.1 < TL < 35.5 cm, 5.59 < TW < 499.44 g) was examined from January 2007 to December 2009. The relative importance index (% IRI) combining the three main descriptors of the presence of different ingested preys (%F, %N, %W) was used to characterize the relative importance of different food taxa. Feeding strategy and food habits are determinate. Qualitative and quantitative variations in diet were studied according to seasons, size and sex. The average annual digestive vacuity is 19.92%. Differences observed between seasons were not significant (χ² = 6.882; p = 0.075). Lithognathus mormyrus is a benthopelagic and carnivorous fish. The main diet items are in order of importance: Mollusca, Chordata, Foraminifera, Annelida, Arthropoda, Echinodermata, Macrophyta and Cnidaria. A total of 7927 preys were identified to a total weight of 91 g, which represents an average number and weight per individual of 19 preys and 0.21 g respectively. Molluscs are the dominant prey whatever the season, size and sex. Despite the dominance of malacological ingested preys, statistical analysis revealed changes in diet between winter and autumn, and between small and large individuals.

Résumé: Nine currently accepted species of the genus Sargassum (Phaeophyceae) have been recorded from the Mediterranean Sea: S. acinarium, S. desfontainesii, S. flavifolium, S. furcatum, S. hornschuchii, S. muticum, S. ramentaceum, S. trichocarpum and S. vulgare. Two of them, S. desfontainesii and S. furcatum, are Atlantic species, the Mediterranean range of which is restricted to the Alboran Sea, close to the Strait of Gibraltar. Three species, S. hornschuchii, S. ramentaceum and S. trichocarpum are endemic to the Mediterranean. The presence of S. flavifolium in the Mediterranean, a north-eastern Atlantic species, is at least in part based upon a misidentification and therefore requires confirmation. A taxon collected near Algiers and Annaba (Algeria), here referred to as ‘Sargassum sp. from Algeria’, although sharing most characters with S. flavifolium, also presents some distinctive characters. In the absence of genetic data, confirming or not its taxonomic value, and in the lack of studies on the herbaria containing the types of many species currently considered as synonyms of S. flavifolium, but which are possible candidates for accommodating the Algerian specimens, the authors prefer a conservative approach. They do not describe a new species, which would be premature, but draw attention to a taxon which may be more widely distributed in the Mediterranean rather than solely along the Algerian coasts.

Résumé: Nearshore shallow waters are important ecosystems. They fulfill many different vital functions for fishes, providing food and shelter from predators, and a nursery ground for numerous species. The aim of this study was to investigate spatial and temporal variations of fish assemblages in the nearshore waters along Annaba coast. Monthly beach seine hauls were performed between 0 and 1.5 m depth at 3 sites: Ain Achir, Belvédère and la Caroube. Fish diversity, spatiotemporal variations in fish assemblages, and relationships between environmental variables and ecological factors were analyzed. A total of 5687 individuals, representing 46 species from 21 families, were collected during the 12 months of sampling. Juveniles represent more than 90 % of fish assemblages. Species richness and abundance were highest during late spring and summer, and lowest in winter and early spring. However, there were no significant differences in the fish assemblage at the spatial scale. Water temperature was the most important environmental factor influencing fish species richness and abundances. The combination of the fish assemblages and environmental variables determined in this study contribute to a better understanding of the ecological networks of Annaba nearshore, thus providing useful data for its conservation and management.

Résumé: The diet of the greater forkbeard Phycis blennoides (Brünnich, 1768) of the Algerian coast was studied between December 2013 and June 2015, providing information on its ecology for a better understanding of the feeding strategy. A total of 956 individuals, whose total length (TL) varied between 9.7 and 54.5 cm and weight (W) between 2.80 and 1334.11 g, were examined. The index of relative importance (%IRI), combining the three main descriptors of the presence of different ingested prey (%F, %N, %W), was used to characterize the relative importance of different food taxa. Qualitative and quantitative variations in diet were studied according to sex, size and seasons. The average annual digestive vacuity index (%V) was 5.51. It did not vary between seasons (x²cal = 5.43, x²th = 7.82, α = 5%) and size (x²cal = 2.08, x²th = 5.99, α = 5%), but was different between male (%V = 4.94) and female (%V= 12.78). Qualitative analysis of stomach contents reveals a fairly diverse range of predation with 1342 preys counted for a total weight of 462.84 g, which corresponds to an average number (AN) and weight (AW) of 3.03 and 1.04 g, respectively. This species feeds on benthic preys, composed mainly of natantia crustaceans (%IRI = 44.84) and teleost fish (%IRI = 2.61) with intraspecific preys (%IRI = 6.15). This cannibalism was frequent in specimens with a TL that exceeds 20 cm; it was even more frequent in females as well as in winter. Significant differences in feeding habits of P. blennoides occurred according to sex, fish size and between seasons. The trophic level (TROPH) was high (3.66 < TROPH < 3.97), corresponding to carnivorous character

Résumé: The aim of the study was to determine seasonal variations of two biomarkers of oxidative stress, Glutathione (GSH) and Glutathione S-transferases (GSTs), in sponge Sarcotragus spinosulus Schmidt, 1862 (Porifera Irciniidae). The samples were collected during the four seasons in 2016-2017 at two sites in the Gulf of Annaba (northeast of Algeria): Cape de Garde, which is some distance from any source of pollution, is considered a relatively clean site, while Alzon is a site exposed to various sources of industrial, urban and harbour pollution. The results show a significant seasonal decrease in GSH rate in Alzon compared with those at Cape de Garde. Moreover, GST activity increased significantly in Alzon relative to Cape de Garde site, with a maximum activity showed in autumn. This difference between those two sites was observed for all seasons, with more effect in spring and winter. The results obtained showed that under stressful conditions due to anthropogenic factors, some physiological processes of sponges can be affected. Thus, S. spinosulus appears to be a suitable sentinel species for the assessment of ecotoxicological risk in the Gulf of Annaba. Sponges present most of the characteristics researched in bioindicators of pollution and consequently have been proposed to constitute a ''Sponge Watch Program''.

Résumé: The diet of the red mullet Mullus barbatus (L., 1758) off eastern coasts of Algeria was studied between December 2007 and November 2008. A total of 573 individuals with lengths between 10 and 22 cm and of total weight ranging from 11 g to 130 g were examined. Qualitative and quantitative analyses were performed according to sex, state of sexual maturity of the predator (juveniles and adults) and seasons. The average annual index of vacuity was 37.87 % and varied significantly according to seasons (χ ² = 169.91; p ≤ 0.05), sex (χ ² = 28.49; p ≤ 0.05) and between juveniles and adults (χ ² = 8.05; p ≤ 0.05). A total of 1491 preys (63.4 g) belonging to 11 items (Crustacea, Mollusca, Annelida, Actinopterygii, Bryozoa, Nemathelmintha, Plathelmintha, Cnidaria, Echinodermata, Porifera and Macrophyta) was recorded, which corresponds to a mean number of four preys per full gut examined. The mean prey weight per gut was 0.2 g. Statistical comparison using ANOSIM test showed that the abundance of prey changes significantly according to seasons, sex and sexual maturity. In spite of numerical and weight fluctuations of the ingested preys, statistical comparison using Spearman rank coefficient (ρ) did not show any qualitative and quantitative changes of M. barbatus diet whatever the season, the sex and the sexual maturity. © 2018 Universite de Paris VI (Pierre et Marie Curie). All rights reserved.

Résumé: The diet of the goldblotch grouper Epinephelus costae of the eastern coast of Algeria was studied from March 2011 to February 2012. A total of 275 individuals, whose total length varied between 21.1 and 79.79 cm and weight between 103.13 and 5390.00 g, were examined. The index of relative importance (%IRI) combining the three main descriptors of the presence of different ingested prey (%F, %N, %W) was used to characterize the relative importance of different food taxa. Qualitative and quantitative variations in diet were studied according to sexual maturity (immature and mature), sex (male and female), size (small, medium and large) and seasons. The average annual digestive vacuity is 17.82%. It does not vary according to sex, size or maturity, but is different between summer and winter. Qualitative analysis of digestive contents reveals a fairly diverse range of predation with 319 prey counted for a total weight of 934.85 g, which corresponds to an average number (Nm) and weight (Wm) of 1.4 and 4.14 g respectively. This species feeds on benthopelagic prey composed mainly of bony fish (%IRI = 76.16), pancrustacea (%IRI = 16.14) and molluscs (%IRI = 6.24). All other prey were accessory (plants) or accidental (annelids). Significant differences in feeding habits occur according to seasons and fish size.

Résumé: The peacock wrasse Symphodus tinca is an abundant and common species along the coast of Algeria. The aim of this study is to provide qualitative and quantitative information on the feeding strategy and food habits of this species in Eastern Algeria. Digestive tracts of 572 specimens with total length ranged from 4.9 to 31.3 cm, and total weight from 1.41 and 420.11 g, were analyzed. The vacuity index (%VI), the index of relative importance (%IRI) and trophic level (TROPH) were studied. Differences in diet depending on season, fish sex and sexual maturity were also checked by statistical analysis. The average annual coefficient of digestive vacuity was 8.74% (50 empty digestive tracts). This percentage varied over the year, with a maximum during the winter and spring which coincides with the spawning period (March-June). The index of relative importance showed that crustaceans were preferentially consumed, whereas sipunculans and mollusks were secondary preys. According to Spearman rank correlation coefficient (rho), the diet composition was homogenous between season, sex and maturity. However, the proportion of ingested peracarid, particularly amphipods and isopods, was more important in immature than in mature individuals. Symphodus tinca is not only omnivorous, but also generalistopportunist predator with a preference for invertebrate. Nevertheless, it revealed a trophic specialization toward sipunculans.

Résumé: The aim of this work was to study some aspects of the reproduction of Symphodus tinca in the North-Eastern of Algeria in order to improve current knowledge of this species for its sustainable exploitation in the area. In this context, fecundity is studied for the first time. A total of 572 individuals were sampled between January and December 2011. Some biological characteristics of the species were examined: sex-ratio, spawning season, gonad maturation, size-at-maturity, fecundity and ovarian histology. Analysis of the sex ratio showed that females were more abundant throughout the year (M/F = 0.74:1). Spawning took place from March to June, peaking in April. There was no histological evidence of sex change, suggesting the peacock wrasse may be a gonochoric species. Total length at first maturity was similar between the sexes, at 13.05 cm for females and 13.87 cm for males. The mean diameter of oocytes in advanced vitellogenesis is 227 +/- 69 mu m (90-437 mu m; number of oocytes = 1000). Absolute fecundity (Fa) ranged from 2935 to 34996 eggs with a mean of 11423 +/- 6618 eggs. The relationships between absolute fecundity and total length, eviscerated weight and gonad weight are respectively: Fa = 4.99TL(2.66), Fa = 112.3EW(1.05), Fa = 2914.3GW(0.82). The number of eggs.g(-1) of female eviscerated weight ranged from 73 to 284 eggs.g(-1), with a mean value of 149 50 eggs.g(-1). Histological criteria allow the determination of five easily identified maturity stages.

Résumé: The objective of this study was to determine the basic population-specific parameters necessary for fish stock assessment in the Gulf of Annaba and to compare these with data from other Mediterranean regions. Black sea bream Spondyliosoma cantharus (Linnaeus, 1758) (N = 501) were collected monthly from January to December 2008 along the Algerian eastern coasts. More than 22 fish were collected each month and ranged in size from 13.4 to 40 cm total length, weighing from 36 to 1080 g eviscerated weight. Biological sampling included weighing and measuring the fish, gonad weighing, sex and maturity stage determination, and age estimation through otolith readings. Validity of the otolith readings for estimating age and growth was supported using the back-calculation method. Estimated parameters of the von Bertalanffy model are: L∞ = 33.54 cm, W∞ = 633.46 g, k = 0.52 year−1 and to = −0.04 year. The growth performance index (φ) is: 2.76. The length-weight relationship is: EW = 4.4.10−6 TL3.23. The spawning period occurred from February to May, while the gamete emission peaked in April. Females reached sexual maturity at 19.3 cm (2 years) and males at 21.3 cm (3 years). Sexual inversion occurs at approximately 24.3 cm. Spondyliosoma cantharus was characterized as being a protogynic hermaphrodite.

Résumé: This paper reports additional records of the Indo-Pacific fish Synagrops japonicus (Doderlein, 1884) in Western Mediterranean. Twenty juveniles of this species ranging from 4 to 4.8 cm (TL) were caught in Annaba Bay, Algeria, using beach seine, in Summer of 2011 (9 specimens, 4 ≤ TL ≤ 4.6 cm) and 2012 (11 specimens, 4.2 ≤ TL ≤ 4.8 cm). Some hypotheses on the origin of this unusual presence are discussed.

Résumé: The zebra seabream Diplodus cervinus cervinus (Lowe, 1838) belongs to the Sparidae family and is common along the Algerian coast. The fishing of this species is coastal and its presence on the shelves is usually accidental. Compared to other Sparidae of economic interests, this species is largely unknown. This study concerns age, growth and reproduction of 190 D. cervinus cervinus (9.8 < TL < 52.7 cm ; 19 < TW < 2100 g) of eastern coast of Algeria. Direct scale readings were made by counting the number of rings, and the results here compared with the data obtained by backcalculating the length at different ages. The individuals in the sample were aged between 1+ and 13+ years. Growth parameters of the von Bertalanffy equation were Lt∞ = 68.83 m, K = 0.105 and t0 = –0.747, with growth performance index φ = 0.86. This index is weak in comparison with that recorded in South African coasts. Length-weight relationship was We = 0.039 Lt2.74. The reproduction period of the whole population occurs between February and September, and the first sexual maturity starts from 25 cm in total length.

Résumé: In Algeria, the presence of Artemia is confirmed at five sites, among which the hypersaline Sebkha Ez-Zemoul, a shallow depression situated in a semi-arid region in the northeast of Algeria at 900 m above sea level. Four species of crustaceans were found to be associated here with Artemia salina: Phallocryptus spinosa, Cletocamptus retrogressus, Moina salina, and Heterocypris sp. During the wet periods of the years 2003 and 2004, A. salina and C. retrogressus were the most frequently observed. P. spinosa co-occurred with A. salina during a short period in January 2003 and May 2004. The densities of the various species were higher during the first wet period (2003) when the water was diluted, and thus less saline. Salinity undoubtedly is an important factor controlling the population dynamics of these species.

Résumé: Composition and variations of the fish assemblage of Posidonia oceanica (L.) Delile, seagrass meadows in Annaba bay (Algeria). — During an annual cycle (July 2004 - June 2005), two coastal sites, one far away from anthropic action (site A : Aïn Achir) and the other subjected to immediate discharge of waste water (site B : la Caroube), were sampled during the day (8 h -18 h) and by night (19 h - 7 h), with a net (50 m long, 2 m high) located at a depth of -5 m. According to the frequency of fish species captured, their ecological status was determined. The Shannon-Weaver diversity index (H’) was calculated to better understand the structure and organization of fish assemblages in both sites. In site A, 19 species belonging to 8 families were fished during the day. At night, the fish assemblage was represented by 15 species and 9 families. The family Sparidae was the most diversified, followed by Labridae and Serranidae. Labridae were the most numerous family by day and by night. Numbers of species and individuals collected in site B during the day (16) as well as by night (11) were significantly lower than those of site A. During daytime, diversity (H’) and equitability (R) indices were respectively 2.51 and 0.33 in site A and of 2.87 and 0.43 in site B. At night, diversity index was lower (site A : 0.64 and site B : 2.55) and equitability was close to 0.41 in the two sites.

Résumé: Ecological and biological characteristics of Artemia salina (Crustacea, Anostraca) in the sebkha Ez-Zemoul, northeastern Algeria. — This study concerned some biological and ecological aspects of Artemia salina (Branchiopoda, Anostraca) from the sebkha Ez-Zemoul, situated in northeastern Algeria (35° 53’ N - 06° 30’ E). The survey of the demographic structure and density of Artemia population between January 2003 and February 2005 shows that this brine shrimp appeared in November after the cyst hatching, reached a maximum density in March (56 ind.L-1 in 2003 and 38 ind.L-1 in 2004) and disappeared completely in July. The sex ratio was always in favour of males. Its values were very high (1.77 - 31.80). Males were smaller than females. Their respective lengths varied, according to the sampling period, between 7.1 mm and 8.8 mm and between 8.7 mm and 10.4 mm. The length of females at first sexual maturity varied between 7 mm (November) and 9 mm (April). Oviparity was the main mode of reproduction (90 - 100 %). Females were relatively fertile with an average brood size comprised between 19.50 (May 2003) and 104.7 (March 2003) offsprings/female.

Résumé: The striped red mullet Mullus surmuletus (L., 1758), a Mullidae, is common along the Algerian coast. This study con-cerns the composition and variations of its diet in the eastern coast of Algeria. Qualitative and quantitative analyses wereperformed according to the size of the predator (juveniles and adults) and the different sampling seasons. The gut contentsof 380 specimens, ranging between 12.2 and 28.8 cm (TL) and of total weight ranging from 21.5 to 321 g, were exam-ined between January and December, 2002. They were fished using gill nets in mixed bottoms (rocks, meadows). Trophicactivity was assessed monthly using the digestive vacuity coefficient (Cv). The IRI was used to compare the quantitativecomposition of the diet. In total, 131 guts were empty, which corresponds to a digestive vacuity coefficient of 34.47 %.This low value, noticed also during the various sampling seasons (28.4% < Cv < 40.62%) and according to fish size (adults:Cv = 35.5%, juveniles: Cv = 31%), confirms the voracity of M. surmuletus in the study zone. Cv varied from 13.3% (August)to 52.7% (December) and from a geographical area to another: Cv = 63.8% in the gulf of Tunis; Cv = 17.26% in Crete Islandin Greece. A total of 1986 prey were consumed, weighing 61.69 g together, which corresponds to a mean number of eightprey per full gut examined, with a mean weight of 0.25 g per gut. This species is omnivorous and crustaceans constitutesthe preferential prey (%IRI = 85.19). Polychaetes come in second position (%IRI = 11%) but are considered to be second-ary prey. The domination of crustaceans, particularly amphipods, is also noticed according to sampling seasons and fishsize. Numerous studies showed that decapods constitute the bulkiness prey ingested by Mullidae of the Mediterranean Sea,which is not the case in the Gulf of Marseilles, in the Gulf of Palermedans, in the Gulf of Castellammare and on Corsicacoasts, where polychaetes predominate. The most common decapods in the diet of the striped red mullet off eastern coast ofAlgeria are the small shrimp Caridae Processa macrophtalma (IRI = 37.5) and the crab Polybius sp. (IRI = 62.87). AdultsM. surmuletus ingested exclusively benthic prey, notably crustaceans, polychaetes, molluscs, echinoderms and small fish.The juveniles striped red mullet (LT < 15 cm) prefer amphipods, but their diet change from a geographical zone to another.

Résumé: The diet of Diplodus sargus sargus (linnaeus, 1758) of eastern algerian coasts was studied from January to December2006. a total of 424 specimens, with total length between 112 and 346 mm were studied. Quantitative and qualitative varia-tions of the diet were assessed according to sexual maturity state (immature: Lt ≤ 205 mm; mature: Lt > 206 mm), sex (maleand female), and seasons. The average annual coefficient of digestive vacuity was 25% and varied significantly accordingto seasons (χ2 = 41.4 ; p ≤ 0.001) and sexual maturity (χ2 = 11.1 ; p ≤ 0.001). However, no significant difference betweenmales and females was noticed (χ2 = 3.6 ; p > 0.05). Qualitative analysis of digestive contents highlighted a diversifieddiet with 3705 counted prey (total weight of 1633 g), belonging to 15 different items (Mollusca, crustacea, Macrophyta,Osteichthyes, annelida, echinodermata, Bryozoa, Porifera, echiura, hemichordata, cnidaria, Sipuncula, Platelmintha,nemathelmintha, Pycnogonida). Omnivore, D. sargus sargus eats benthic prey, essentially Mollusca (Pelecypoda, Gas-tropoda, Polyplacophora), crustacea (Decapoda, cirripeda, amphipoda, Isopoda) and also Macrophyta (rhodophyta andMagnoliophyta). Prey classification using the percentage of relative importance index (% IRI) allowed to group Molluscain the preferential food category, with prevalence of Pelecypoda (IrI = 23.3%) and of Gastropoda (IrI = 13.1%). crusta-cea (IRI = 18.2%) and Macrophyta (IRI = 13.5%) were classified as secondary food items. All other items (Osteichthyes,annelida, echinodermata, Bryozoa, Porifera, echiura, hemichordata), were accidentally ingested (IrI < 5%). Statisticalcomparison, using Spearman range coefficient (ρ), did not showed no significant variation of the diet, which remainedhomogeneous according to seasons (winter-spring: ρ = 0.6, tobs = 3.3; spring-summer: ρ = 0.9, tobs = 8.0; summer-autumn:ρ = 0.8, tobs = 6.3; autumn-winter: ρ = 0.8, tobs = 6.0), prey height (ρ = 0.9 ; tobs = 10.9) and sex (ρ = 0.9 ; tobs = 12.2 ;p ≤ 0.01). Diplodus sargus sargus from the eastern algerian coast is a voracious predator, which feeds according to aseasonal rhythm. as in many regions of the Mediterranean Sea, seabream is typically omnivore and it is an opportunisticconsumer, which, despite the extent of its food spectrum, prefers molluscs. While growing, the seabream widens its foodspectrum, while conserving the prey when being young. The diet is homogeneous both during the year and for the twosexes, and it becomes diversified while acquiring sexual maturity, but with no significant variation.

Résumé: Some biological and ecological aspects of Artemia salina from Chott Marouane (northeast Algeria) were studied during the wet period of 2001. The population develops between late winter and spring. It is adapted to the high salinity of the site, ranging between 230 and 360 psu. Sex-ratio is in favour of males. These are smaller in size than females: their respective average lengths are 6.02 and 7.01 mm. Oviparity is the main mode of reproduction (more than 86.6%). Females produce between 4.9 and 17 cysts/brood, according to the sampling period.

Résumé: Studies revealed the role of Artemia salina as intermediate host in the life-cycle of a cestode species parasitizing flamingos, i.e. Flamingolepis liguloides. Cysticercoids of this parasite were found for the first time in the Algerian populations of Artemia salina in winter of 2000 and 2001 in Chott Marouane and spring of 2003 in Sebkha Ez-Zemoul. The prevalence ranged between 10 and 33% for the two examined Artemia populations. The intensity of infection was 1–3 cysticercoids per individual. The abdomen was the most targeted site of infection (95% of the population of Sebkha Ez-Zemoul) followed by the thorax and the ovisac. Infected females were less fertile than uninfected ones (24.83 vs 43.70 cysts/brood) in Sebkha Ez-Zemoul or castrated in Chott Marouane.

Résumé: Dietary habits and condition of gilt-head sea bream Sparus aurata (Teleostei: Sparidae) in the Mellah lagoon (NorthEastern Algeria). The feeding habits of Sparus aurata in the Mellah lagoon (northeastern Algeria) was studied using three simple methods (frequency of occurrence of prey, numeric percentage and percentage weight) and a feeding coefficient. Monthly variations in the stomach vacuity were also examined. The diet includes a wide variety of food organisms, fish and molluscs bivalvia constituting the favorite preys. A relationship between feeding activity and body condition was observed.

Résumé: Quality of Artemia from Chott Marouane (Northeast Algeria) was evaluated using biometrics, biochemicals, and cysts hatching descriptors. Hydrated cysts measured 236.5 μm, while the freshly hatched nauplii of Artemia measured 428.7 μm for a weight of 2.3 μg. Cysts that were treated with hydrogen peroxide had a hatching percentage of 69%, which corresponded to an efficiency of 0.44 g. Time required to obtain 90% hatch is 37.5 h. The hatching synchronization time was of 12.5 h. The fatty acids identification showed that the n−3 serial was strongly dominant representing 21.71% to 25.21% of the total fatty acids analyzed. Low level of EPA (1.25%) and DHA absence were noted.

Résumé: Un inventaire qualitatif de la faune ichtyologique est réalisé dans la région d’Annaba, sur des fonds hétérogènes, rocheux (à herbiers,corraligènes) et meubles (sableux, vaseux, sablo-vaseux, coquilliers), dans la tranche bathymétrique comprise entre 0 et 500 m. L’essentielde l’effort d’inventaire concerne l’étage infralittoral (0 - 40 m). Une attention particulière est accordée à l’ichtyofaune de la frange côtière,entre 0 et 10 m. Les apports de la pêche professionnelle et les observations visuelles en plongée sous-marine nous ont permis d’identifier165 espèces de poissons, dont 139 téléostéens et 26 sélaciens. Le premier groupe est représenté par 57 familles dont 21 familles deperciformes

Résumé: Le regime alimentaire des loups Dicentrarchus labrax du golfe d'Annaba (8°15'E, 36°68'N et 7°16'E, 36°38'N) est etudie au cours d'un cycle annuel. 568 individus de longueur totale comprise entre 15,5 et 61,6 cm ont ete examines. Le coefficient moyen de vacuite stomacale est de 36,9%. Ses valeurs mensuelles mettent en evidence un rythme alimentaire saisonnier. L'alimentation est a base de poissons et de crustaces. La richesse taxonomique totale des proies ingerees est egale a 20; elle augmente chez les juveniles et diminue de l'automne vers l'ete. La composition du regime alimentaire du loup change au cours de la croissance. Les juveniles (15 a 30 cm) preferent les petits crustaces, les alevins et les sardines. Ces dernieres dominent dans les estomacs des individus de la classe suivante (30 a 40 cm), alors que les gros specimens (40 a 60 cm) se specialisent sur les poissons. Le suivi de l'alimentation au cours des saisons met en evidence la singularite du regime de printemps, caracterise par l'apparition de nouvelles proies (Portunus sp., Squilla mantis, Trachurus sp.)

Résumé: Du sperme de daurade Sparus aurata est prélevéà diffkrentes dates de la saison de spermiation. La composition biochimique du plasma séminal est analyské. La concentration des éléments dosés est généralement plus importante que chez les espèces d'eau douce. La teneur en protéines reste constante au cours du temps. La quantité de glucose accuse une diminution à partir de la mi-décembre. Les triglycérides et le cholesterol atteignent des valeurs relativement elevees aux dates limites de la période d'échantillonnage, tandis que le taux de calcium est minimal à la fin de la saison de spermiation.

Résumé: Un inventaire réalisé dans la région de Annaba a permis de recenser 44 mérous Epinephelus marginatus. Ces derniers ont une répartition bathymétrique positivement corrélés à leur taille. Ils colonisent particulièrement les grottes et les failles rocheuses. La majorité des individus sont hors de leur gite et présentent un comportement de fuite lente. Les juvéniles fréquentent les eaux peu profondes et sont souvent indifférents au plongeur ou attirés par lui.

Résumé: The morphology of Epinephelus marginatus from algerian eastem coasts is characterized by morphometric parameters (standard length, head 1ength; dorsal fin length and eye diameter). These biometric parameters are linked to the total individu al or head lengths by a relationship of the form y = axb• Only b value indicates that the diameter of the eye presents a minorant allometry. The age of fishes is determined by the method of retrocalculation and their growth by the Von Bertalanffy model (Loo = 78.53 cm ; K = 0.16 ; to -0.73). Their eviscerate weight-totallength relationship is Pe = 0,810.10.2 Lt3, 14. Thl?linear growth is rapid during the four first years, while the most strong rates of ponderal growth are obtained from the fourth year. The index P indicates a best development of Epinephelus marginatus on algerian coasts. The natural mortality (M = 0.16) and mortality by fishing (F = 1.19) coefficients are relatively high. The rate of exploitation (E = 0.88) indicates a dynarnic imbalance

Résumé: Preliminary data on the distribution and condition of the Posidonia oceanica meadow in the El Kala area (Algeria). A field study was carried out along the coast of the El Kala National Park (Algeria) to determine the areas of major ecological interest which are worthy of more rigorous protection measures under the planned extension of the Park to include the marine environment. The Posidonia oceanica meadow is of particular interest in view of the major role it plays in the Mediterranean coastal ecosystem. Preliminary observations appear to suggest that the meadow here presents certain unusual functional features (especially as regards trophic flux); it is the presence of the meadow that probably explains the exceptional richness of the fauna (echinoderms, fish). However, unsuitable hydrological and sedimentological conditions mean that the meadow cannot grow along the whole coast, which is all the more reason for urgently providing protective measures in those areas where it is present.

Résumé: Quelques aspects écologiques des populations de sars, Diplodus cervinus cervinus (Lowe, 1838) et Diplodus puntazzo (Cetti, 1777), de badèches, Epinephelus costae (Steindachner, 1875) et de corbs, Sciaena umbra (Linnaeus, 1758), ont été étudiés par relevés visuels dans le golfe d’Annaba (Est, Algérie), au cours des années 2003 et 2004. Cette méthode d'échantillonnage in situ nous a permis de recueillir, entre 0 et 41 m de profondeur, des informations préliminaires sur les abondances, la structure démographique, la répartition bathymétrique, le type d’habitat fréquenté et le comportement de ces quatre espèces en présence de l’expérimentateur. Sur un total de 36 plongées diurnes réalisées dans deux sites côtiers, le cap de garde (zone anthropisée), situé à l’ouest, et la plage El Hanaya (zone faiblement anthropisée), située à l’est, nous avons constaté une plus faible fréquence de rencontre et un comportement de fuite plus prononcé des quatre espèces en zone soumise à une pression anthropique (activités nautique et subaquatique, pêches artisanale et sportive). Comparé au comportement de fuite lente des autres espèces, l’attirance envers l’observateur semble être une réaction assez caractéristique chez E. costae. Dans les deux sites, l’habitat de prédilection est représenté par des fonds rocheux constitués essentiellement de blocs. Les substrats mixtes, l’herbier à posidonie, les anfractuosités, les dédales et les sables ne sont fréquentés que sporadiquement.

Résumé: ’étude du cycle de mue, la sécrétion cuticulaire ainsi que le dosage des protéines et des lipides hémolymphatiques sont abordés chez la crevette royale Penaeus kerathurus (Forskal, 1775) en milieu contrôlé (photopériode: 12h/12h, salinité de l’eau de mer: 37 psu, température: 22-25°C). La durée moyenne de la post-mue est de 3,5 jours (13 % du cycle). L’intermue, de durée plus longue (8 à 10 jours), représente 34 % du cycle de mue. La période pré-exuviale constitue 52 % du cycle entier et se distingue par d’importantes variations individuelles allant jusqu’à 3 jours au stade D2. Au cours du cycle de mue, la cuticule subit une dégradation à partir du stade Do-D1, et qui se poursuit jusqu’au stade D3. Au début de la prémue (Do-D1), la cuticule mesure en moyenne 5,2 μm d’épaisseur. Elle atteint 28,5 μm en intermue (stade C) et diminue jusqu’à 18,7 μm à l’exuviation. Parallèlement, le dosage des protéines et des lipides hémolymphatiques au cours des stades B, C, Do-D1, D2 et D3 montre que les concentrations de ces constituants sont maximales en période pré-exuviale et minimales en période post-exuviale.

Résumé: Une étude de la biologie, de l’écologie et de la génétique du mérou brun Epinephelus marginatus (LOWE, 1834) a été réalisée dans la région d’Annaba (nord-est de l’Algérie). Elle apporte de nouvelles informations sur la morphologie de cette espèce, sa croissance, son habitat, son comportement in situ, sa mortalité (naturelle et par pêche), son alimentation en période estivale, sa sexualité et ses relations phylogéniques intraspécifiques. Une compilation bibliographique sur le sujet est présentée en tentant une comparaison avec nos résultats.

Résumé: Une synthèse des données floristiques et faunistiques d'un écosystème lagunaire méditerranéen, le lac Mellah (8°20E - 36°54N est présentée ici . l'importance qualitative des espèces végétales et animales est retracée avant l'aménagement du chenal du lac, réalisée en 1988 ..La production des organismes revêtant un intérêt commercial, en particulier la faune malacologique et ichtyologique est précisée aussi.

Résumé: L’étude présentée ici tente de répondre à un besoin d’informations sur la diversité des gastéropodes en général et sur les Trochidae en particulier le long des côtes de l’est de l’Algérie. Un intérêt majeur est accordé à l’espèce Phorcus(=Osilinus ) turbinatus, en particulier à quelques aspects de son écologie et de sa biologie. Nous avons déterminé par la méthode indirecte de Battacharya en utilisant le logiciel FISAT II les différentes sous populations de P. turbinatus Dans les trois sites, les valeurs observées et théoriques de la croissance linéaire absolue et pondérale sont très proches ce qui indique une bonne description de la croissance par le modèle de Von Bertalanffy. La croissance relative est globalement minorante pour P. turbinatus de Rizi Amor et le site Mollo. Elle est isométrique à oued El Ganem, pour les mâles et les femelles. L’analyse statistique (ANOVA, MANOVA) a montré que la croissance relative des paramètres biométriques est influencée probablement par la pollution domestique du milieu.

Résumé: Les poissons, comme toute espèce animale, sont parasités, soit par des ectoparasites qui se fixent sur différentes parties corporelles externes (branchies, nageoires, tégument), soit par des endoparasites qui viennent infecter divers compartiments anatomiques (muscle, gonade, vessie natatoire, tube digestif). En fonction de leur cycle biologique, ces parasites, souvent représentées par des formes larvaires, vont indirectement infecter le prédateur via l’ingestion de ces proies alimentaires (vers, crustacés, etc.). En raison de la complexité des processus épidémiologiques et la diversité des hôtes, il est souvent difficile de prévenir ou de lutter contre la présence de ces endoparasites, qui une fois ingérés accidentellement par le prédateur peut engendrer souvent des affections gastro-intestinales (anisakiase ou anisakidose) chez l’homme lorsque les conditions de stockage et/ou de cuisson ne sont pas respectées. Cette étude est une contribution à la recherche d’endoparasites dans le contenu digestif du sar commun Diplodus sargus sargus, un sparidé très fréquent sur les étals et de haute valeur commerciale sur les côtes ouest d’Algérie. Sur un total de 245 spécimens examinés entre mai et novembre 2023, nous avons identifié seulement la présence d’un seul nématode et de 13 annélides, dont 7 au printemps et 6 en été. Ces proies sont généralement ingérées accidentellement selon l’indice d’importance alimentaire (IRI). Leur présence dans le contenu digestif est considérée sans danger pour la santé du consommateur.

Résumé: Les poissons, comme toute espèce animale, sont parasités, soit par des ectoparasites qui se fixent sur différentes parties corporelles externes (branchies, nageoires, tégument), soit par des endoparasites qui viennent infecter divers compartiments anatomiques (muscle, gonade, vessie natatoire, tube digestif). En fonction de leur cycle biologique, ces parasites, souvent représentées par des formes larvaires, vont indirectement infecter le prédateur via l’ingestion de ces proies alimentaires (vers, crustacés, etc.). En raison de la complexité des processus épidémiologiques et la diversité des hôtes, il est souvent difficile de prévenir ou de lutter contre la présence de ces endoparasites, qui une fois ingérés accidentellement par le prédateur peut engendrer souvent des affections gastro-intestinales (anisakiase ou anisakidose) chez l’homme lorsque les conditions de stockage et/ou de cuisson ne sont pas respectées. Cette étude est une contribution à la recherche d’endoparasites dans le contenu digestif du sar commun Diplodus sargus sargus, un sparidé très fréquent sur les étals et de haute valeur commerciale sur les côtes ouest d’Algérie. Sur un total de 245 spécimens examinés entre mai et novembre 2023, nous avons identifié seulement la présence d’un seul nématode et de 13 annélides, dont 7 au printemps et 6 en été. Ces proies sont généralement ingérées accidentellement selon l’indice d’importance alimentaire (IRI). Leur présence dans le contenu digestif est considérée sans danger pour la santé du consommateur.

Résumé: Au cours de cette dernière décennie, l’aquaculture a connu un rythme accéléré dans une perspective de réduire l’impact de la pêche sur les ressources biologiques côtières d’intérêt économique. Selon le dernier rapport de la FAO sur la situation des pêches et de l’aquaculture, la production d’espèces animales en 2022 issue de l’aquaculture a dépassé pour la première fois (51%) celle de la pêche de capture, l’aquaculture continentale produisant 62,6% des animaux aquatiques d’élevage. La pisciculture marine côtière en Méditerranée est représentée essentiellement par l’élevage du bar Dicentrarchus labrax et Sparus aurata dont la zootechnie est parfaitement maitrisée dans de nombreux pays, notamment en Turquie et en Grèce, les deux plus grands producteurs de ces deux espèces. Dans une perspective de diversification des espèces marines d’élevage, la communauté scientifique est toujours en quête de données scientifiques sur de nouvelles espèces robustes et rustiques à haute valeur marchande afin de satisfaire le consommateur le plus exigeant, comme les asiatiques. Cette étude qui répond parfaitement à cette problématique a pour objectif de fournir des données sur la performance de la croissance d’un téléostéen côtier le sar commun Diplodus sargus sargus, un sparidé qui partage le même habitat de la dorade S. aurata. Les paramètres de croissance obtenus par le modèle de von Bertalanffy sont comparés entre les différentes populations algériennes puis par rapport à ceux de S. aurata dans une perspective aquacole. Sur les côtes de l’est algérien, la longueur totale (Lt) atteint 36,3 cm avec un coefficient de croissance (k) de 0,154 an⁻¹, tandis qu’à l’ouest, la Lt =36,0 cm et le k = 0,948 an⁻¹. La taille à la première maturité sexuelle à l’Est est de 20,2 cm pour les mâles et 20,0 cm pour les femelles, alors qu’au centre la taille à la première maturité sexuelle est estimée à 20,55 cm pour les deux sexes. Les données biologiques capitalisées sur la dorade S. aurata montrent que la longueur totale de cette espèce est similaire à celle de D. sargus sargus, avec des coefficients de croissance situés entre 0,2 et 0,3 an⁻¹. La dorade atteint sa maturité sexuelle entre 22 et 25 cm. Au vue de ces premiers résultats, les paramètres reproductifs et de la croissance du sar commun et de la dorade sont très similaires, renforçant ainsi l’idée que le sar commun est un choix prometteur pour la pisciculture marine en système intensif.

Résumé: The study presented here is a contribution to the knowledge of the biology of the white sea bream Diplodus sargus sargus (L., 1758) from the Algerian west coast, with a particular interest in relative growth. In this region, this demersal species is of great economic importance for artisanal fishing (small-scale coastal fishing) and recreational fishing. Despite its economic and ecological importance, and even if certain studies have been carried out in the east and center of the country, scientific data on the western Algeria population are absent.

Résumé: The study presented here is a contribution to the knowledge of the biology of the white sea bream Diplodus sargus sargus (L., 1758) from the Algerian west coast, with a particular interest in relative growth. In this region, this demersal species is of great economic importance for artisanal fishing (small-scale coastal fishing) and recreational fishing. Despite its economic and ecological importance, and even if certain studies have been carried out in the east and center of the country, scientific data on the western Algeria population are absent.

Résumé: The study presented here is a contribution to the knowledge of the biology of the white sea bream Diplodus sargus sargus (L., 1758) from the Algerian west coast, with a particular interest in relative growth. In this region, this demersal species is of great economic importance for artisanal fishing (small-scale coastal fishing) and recreational fishing. Despite its economic and ecological importance, and even if certain studies have been carried out in the east and center of the country, scientific data on the western Algeria population are absent.