Mugil

Abstract: Several biochemical parameters have been analyzed in the livers offish from south Atlantic Spanish littoral areas exhibiting different pollution levels. Mugil sp. (grey mullet) from the Huelva Estuary contained higher concentrations of metals, such as Fe and Cu, than those from a reference area (Cadiz Bay). Similarly, sediments from Huelva showed high concentrations of polyaromatic hydrocarbons, polychlorinated biphenyls, and pesticides. The contaminated animals were subjected to oxidative stress, as indicated by their oxidized glutathione redox status, but showed low malondialdehyde and lipohydroperoxide levels. A battery of antioxidant enzymes increased simultaneously in contaminated fishes, including glutathione peroxidase, superoxide dismutase, catalase, glucose-6-P dehydrogenase, and glutathione reductase. These data suggest that contaminated fish were well protected from oxidative stress. Highly significant increases were also observed in cytochrome P-450-associated ethoxyresorufin-O-deethylase acti...

Abstract: Spatial and temporal variation in fish assemblage structure of Koycegiz LagooneEstuarine System (KLES), located on the northwestern Turkish coast of Mediterranean, was investigated along an estuarine gradient where salinity ranged from 5 in upper reaches to 40 in lower reaches during October 1993eSeptember 1994. Throughout the study, 42 species, consisting of marine (25), marineeestuarine-dependent (12), freshwater (3), catadromous (1), and estuarine resident (1) forms, were collected in trammel nets. Although species richness of marine species was greater than that of other groups, numerical contribution by marine species to the total catch was only 16%. Tilapia spp., the most abundant species mostly during summer and early spring at upper reaches, contributed 17% of the total samples. Among the seven species of Mugilidae, which contributed 42% of the total catch, Mugil cephalus, Liza aurata, and Liza salines contributed 10, 13, and 10% of the total catch, respectively. Consistent with findings from other studies, species richness and abundance were highest during late spring and summer and the lowest during winter and early spring. Samples from sites at or near the sea had more marine species. Samples from upper reaches had more freshwater and marineeestuarine-dependent species. Canonical correspondence analysis (CCA) indicated that salinity and turbidity were the most important environmental parameters affecting fishes. Sites near the sea were associated with high salinity and low turbidity, and sites in upper reaches had low salinity and high turbidity. Thus, the pattern observed in fish assemblage structure appears to be strongly influenced by species’ responses to dominant salinity and turbidity gradients. 2005 Elsevier Ltd. All rights reserved.