Seasonal discards and by-catch of hydraulic dredges targeting striped venus clams, Chamelea gallina, from the Black Sea coasts of Turkey were determined. Data presented in this study were collected by researchers aboard between September 2009 and April 2010. Results indicated that discards were 36% of the landed product, of which 19% was composed of undersized (<17 mm) clams. During the study, a total of 38 species were identified and the hermit crab (Diogenes pugilator) and the gastropod Rapana venosa were the two main species captured as discard from all sampling stations in every season. Species diversity and evenness index values, of winter and spring hauls were significantly different from autumn ones.