Gillnet selectivity is poorly understood for most freshwater fish species, particularly invasive alien species. However, their use to determine mesh could be essential establishing management measures, such as the selective removal of exotic This study aims assess size species in a restored lentic ecosystem. Therefore, we analysed gillnet based on experimental fishing trials performed by using ...

Recruitment success of roach varied dramatically between 1979 and 1982 in Alderfen Broad, a small lake in eastern England. When fry were abundant (in 1979 and 198 1, but not in 1980 or 1982) the summer zooplankton became sparse and was dominated by copepods and rotifers. In years of good recruitment, as each of the preferred cladoceran prey species entered the diet of underyearling roach, its d...

The Boojagh international wetland with a surface area of 80 hectares and 25 fish species is located in the southwest shores of the Caspian Sea (Guilan province, Iran), but there is no report about fish parasites in this wetland. In the present study, a total of 553 individuals of 8 fish species including Cyprinus carpio (n=71), Abramis bjoerkna (n=153), Carassius auratus gibelio (n=89), Esox...

The present study has been conducted on Caspian Roach (Rutilus rutilus) so that the impact of different concentrations lead on blood hematological, biochemical, and immunological indicators could be investigated. The roach (Rutilus rutilus), used in this study, was 3.3±0.3 g heavy and 4±0.80 cm long in average. The fish were exposed to a low concentration of 10% LC50 and high concentration of 5...

Disruption in gonadal development of wild roach living in U.K. rivers receiving large volumes of treated sewage effluent is manifest in a variety of ways, ranging from malformation of the germ cells and/or reproductive ducts to altered gamete production. Intersex fish were also found to have an altered endocrine status and an elevated concentration of plasma vitellogenin. Gonadal growth was inh...