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The aim of this study was to assess heavy metals in liver and muscle tissues of the greater forkbeard, Phycis blennoidesfrom Algerian commercial fisheries.Specimens of this deep-water fish were sampled from seven ports (i.e. Annaba, Azeffoun, Zemmouri, Bouharoun, La Madrague, Cherchell and Mostaganem) along the Algerian coast, between April 2014 and May 2015. Five heavy metals (Pb, Cu, Zn, Ag, Ni) were evaluated in 43 samples (28 muscle and 15 tissues livers) belonging to 30 individuals of P. blennoides. Their total lengths (TL) varied between 12.2 and 54.5 cm and weighting from 11.22 to 1334.11 g in total weight (TW). The analysis was performed using Flameless Atomic Absorption Spectrophotometry (FAAS), after dry and wet acid digestions. Ontogenetic, sexual, spatial and bathymetric variations of heavy metal concentrations were studied. Their presence in both anatomical territories were observed in this species. Muscle presented highs mean values of Ag, Ni and Zn and highs levels of Pb and Cu in the liver. Significant variations (p < 0.05) were noted across sex, size categories, sectors, regions, but not with depths (p > 0.05). This work is the first to assess heavy metals by FAAS in P. blennoidesof the Southwestern Mediterranean, and the only one that determines silver concentrations in deep-fish organs from Africa.

This preliminary study aims at assessing a contamination level of Bejaia Gulf by some Metallic Trace Elements (MTEs) such as zinc, iron, copper, nickel, lead and cadmium. The use of hake, Merluccius merluccius(Linneaus, 1758) as a bio-indicator of these heavy metals, made it possible to put in an obvious the presence of these micropollutants at the level of two target organs, the liver, detoxifying organ and the muscle, the most prized part by consumer. The MTE assays are performed using a Flame Atomic Absorption Spectrophotometer (FAAS). As for the fish contamination level, it is referred to the guide values of the WHO, FAO and Algerian recommendations. Within the framework of our study, the recorded values show that hake accumulates all metal pollutants being analyzed. Iron and zinc exhibit the highest concentration, the presence of nickel and copper were also recorded. Lead and cadmium have critical concentrations exceeding even Algerian standards.

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. blennoidesoccurred according to sex, fish size and between seasons. The trophic level (TROPH) was high (3.66 < TROPH < 3.97), corresponding to carnivorous character.