Applicability of the gape monitor to study flat oyster (Ostrea edulis) feeding behaviour Linda Tonk, Rob Witbaard, Pim van Dalen, Chiu H. Cheng and Pauline Kamermans Aquat. Living Resour., 36 (2023) 6 Published online: 01 March 2023 DOI: 10.1051/alr/2022021