Size-selective predation by round gobies (Neogobius melanostomus) on dreissenid mussels in the field

► We investigate if round gobies prey selectively on different sizes of dreissenids. ► Round gobies crushed over half of the dreissenid mussels they consumed. ► Crushed dreissenids were larger than those swallowed whole. ► Round goby length was positively related to the size of dreissenids consumed. ► Round gobies demonstrated the greatest degree of selectivity for 8-11 mm dreissenids.