In the Chausey archipelago, growth of the burrowing bivalve Venus verrucosa(Mollusca: Veneridae) has been shown to be highly variable between closelylocated sites (<1 km). To explain this small-scale spatial variability, we tested thetrophic hypothesis using both fatty acid markers, and carbon and nitrogen stable isotopes(δ13C and δ15N). Environmentalparameters, including substrate, were also analysed to discriminate their effects onpotential trophic differences. Results of isotopic fractionation and lipid profiles ofwater column and digestive gland samples both showed a large contribution of phytoplanktonto the diet of V. verrucosa. More surprisingly, the same results suggestthat Phaeophyceae and Rhodophyceae macroalgae could contribute to the nutrition ofV. verrucosa as dissolved exudates. Whereas site differences were notobserved between the food sources of V. verrucosa, we showed that growthperformance index was correlated to wave height. Thus, we hypothesized that the high localgrowth variability could be controlled by the hydrosedimentary dynamics. In addition,although no significant growth differences were found between intertidal and subtidalpopulations, better condition index and more total lipids were found in the digestivegland of intertidal V. verrucosa, suggesting potential compensatorygrowth mechanisms.