In this study (Brioukhanov A., Chelebieva E., Kladchenko E., Podolskaya M., Gavruseva T., Andreyeva A. // Gill microbiome of Pacific oysters Magallana gigas following the infection with sponges Pione vastifica), we compared the diversity of gill microbial communities in a group of Pacific oysters Magallana gigas that were parasitized by boring sponges (Pione vastifica), and a control group of healthy oysters without signs of sponge presence on shells.