Search

Copyright of Cybium: International Journal of Ichthyology is the property of Societe Francaise d'Ichtyologie (SFI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One specimen of the yellowtail barracuda, Sphyraena flavicauda Rüppell, 1838, is recorded for the first time in the Western Mediterranean, on the eastern coast of Algeria. The specimen had a TL of 39.5 cm and was caught in February 2019. Its morphometric characteristics are described and the chronology of its spread in the Mediterranean is given. This species is the ninth Lessepsian migrant fish reported from Algeria. [ABSTRACT FROM AUTHOR]

Copyright of Cybium: International Journal of Ichthyology is the property of Societe Francaise d'Ichtyologie (SFI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cybium: International Journal of Ichthyology is the property of Societe Francaise d'Ichtyologie (SFI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background. Southern Mediterranean lagoons are poorly studied. The Mellah Lagoon is the only coastal lagoon in Algeria. Characterized by low anthropogenic pressure it has a crucial environmental and socioeconomic role because of its fishing activities and conservation status. The spatial and temporal variations of fish assemblage structure in relation with the environmental parameters were investigated. This study contributes to a better understanding of the functioning of the Mellah Lagoon, thus providing useful data regarding its conservation and management. Materials and methods. Sampling was carried out monthly during one year at four stations with a beach seine of 3-mm mesh. Environmental variables were measured during each sampling. Canonical correspondence analysis (CCA) and cluster analysis were used to assess environmental influences on fish spatio-temporal assemblages. Results. A total of 11 fish species representing 8 families were collected and examined: Aphanius fasciatus (Valenciennes, 1821); Atherina boyeri Risso, 1810; Liza saliens (Risso, 1810); Liza aurata (Risso, 1810); Mugil cephalus Linnaeus, 1758; Mugilidae gen sp.; Pomatoschistus marmoratus (Risso, 1810); Diplodus sargus sargus (Linnaeus, 1758); Sparus aurata Linnaeus, 1758; Syngnathus abaster Risso, 1827; Anguilla anguilla (Linnaeus, 1758); Hyporhamphus picarti (Valenciennes, 1847). Resident species presented the highest abundance values, accounting for 96% of the total number of fish captured, while marine migrant species that use the lagoon as a nursery ground contributed the most to the community species richness (7 species). Atherina boyeri (87.59% of total catch by number) was the most abundant species. Environmental parameters measured were uniform across the whole lagoon. However, temperature and salinity showed a seasonal pattern. The CCA analysis based on species abundance indicated the absence of clear spatial and temporal patterns in fish assemblage. The majority of the species had mean values of distribution in relation to environmental variables. Conclusion. The fish assemblage of the shallow water (<1.5 m) of the Mellah Lagoon is characterized by a small number of species dominated by resident species. The low species richness, the dominance of resident species, and the weak spatial and temporal patterns in the fish assemblage are mainly the result of a high degree of confinement because of the low freshwater inputs from the wadis and the limited tidally-driven exchanges between the lagoon and the sea. To maintain high biodiversity and a sustainable fishery in the lagoon, it is necessary to develop a management plan which would facilitate a proper water exchange between the lagoon and the sea and would promote colonization of the lagoon by marine species. [ABSTRACT FROM AUTHOR]

Age, growth and reproduction of 493 jewelfish Hemichromis bimaculatus Gill, 1862 in the valley of Oued Righ (Algeria) were studied from December 2010 to December 2011. The total length and weight of the individuals ranged from 21 to 107 mm and 0.20 to 14.9 g, respectively. Monthly follow-up of the scale marginal growth allowed identifying only one growth stop annulus per year, occurring in April. Back-calculations of total length-at-age permitted to determine that the population was composed of three age classes in both sexes. The adjustment to von Bertalanffy growth model was satisfactory with L∞ = 11.6 cm, K = 0.2, to = -0.5. The fitted total length-total weight relationship was W = 0.026 L2.803. Macroscopic examination of gonads and monthly follow-up of gonadosomatic index indicated that spawning occurred once a year between March and June with a peak activity in April-May. The GSI reached a maximum of 1.12% in males and 7.52% in females. The length at first maturity was 4.5 cm for males and 5.7 cm for females. [ABSTRACT FROM AUTHOR]

Copyright of Cybium: International Journal of Ichthyology is the property of Societe Francaise d'Ichtyologie (SFI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Three specimens of silver-cheeked toadfish, Lagocephalus sceleratus (Gmelin, 1789), were caught on eastern coasts of Algeria during the winter of 2013-2014. This is the first record of this invasive species from Algeria, providing further evidence of its occurrence along north-African coasts and confirming its entry into the Western basin of the Mediterranean. The human-health implications of this toxic fish in this region are discussed. [ABSTRACT FROM AUTHOR]

Background. The peacock wrasse, Symphodus tinca (Linnaeus, 1758), is a common Mediterranean fish and the most abundant labrid species on the eastern coast of Algeria. Its age and growth, however, have been poorly studied. Such data are essential for proper fisheries management. The aim of this study is to provide information on the age and growth of this wrasse species from the eastern Algeria based on two different methods of fish age determination. Materials and methods. Age and growth of Symphodus tinca were determined by examining otoliths and scales of the fish sampled between January and December 2011 on the eastern coast of Algeria. Otoliths and scales from 515 and 469 specimens, respectively, were used to determine the age using commonly accepted procedures. Results. The age was successfully determined in 513 (99.61%) otoliths (277 females, 209 males) and in 428 (91.25%) scales (232 females, 173 males), representing age classes between 0+ and 5+ years (1+-3+ years for females and 1+-5+ years for males). The validity of the otolith and scale readings for estimating age and growth was supported by the back-calculation method. The success rate in reading otoliths and scales of Symphodus tinca was very high. The growth pattern is well described by the von Bertalanffy growth equation: from otoliths, L∞ = 26.46 cm, k = 0.79, t0 = -0.12 for females and L∞ = 32.32 cm, k = 0.54, t0 = -0.22 for males; from scales, L∞ = 26.61 cm, k = 0.61, t0 = -0.45 for females and L∞ = 32.50 cm, k = 0.48, t0 = -0.31 for males. Otolithometry and scalimetry gave very close results. The total lengths (TL) ranged from 4.9 to 31.3 cm, and eviscerated weight (We) from 1.38 to 400.65 g. The length-weight relation showed an isometric growth for females (b = 3.01), and negative allometric growth for males (b = 2.86). Conclusion. The age was estimated by otolith and scale reading for males and females where the two methods yielded the similar results. Although the otolith readings presented a better fit (99.61%), scales could also be used with fairly good results (91.25%). In the future, research on the growth of S. tinca either of these two methods can be used to save time. The scale method, however, is certainly the easiest. [ABSTRACT FROM AUTHOR]

Copyright of Cybium: International Journal of Ichthyology is the property of Societe Francaise d'Ichtyologie (SFI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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 were 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 cm, 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. [ABSTRACT FROM AUTHOR]

We characterised four samples of gilthead sea bream from the two western Mediterranean banks with three microsatellite loci and two RAPDs systems. Contrarily to what could be predicted for a highly mobile species with a planktonic larval dispersal phase, we observed a strong and significant genetic differentiation at all loci between the two banks (F(st)=0.069(***)), whereas two samples from the Gulf of Lions were almost identical (F(st)=0.003 ns) while the two from the Gulf of Annaba displayed varied levels of differentiation according to the molecular marker considered. RAPDs showed a similar trend as microsatellites. The reasons for this surprisingly strong genetic differentiation, as compared to what has been observed in other species over comparable geographical distance, may be sought for either in a smaller as suspected larval dispersal, or in the non-neutrality of the loci studied.