Shannon and Simpson indices were calculated from 1000 resamplings of the original table to the lowest number of sequence reads per sample (12,997 sequence reads). Dissimilarities in community structure were studied for all taxonomic levels using the Bray-Curtis dissimilarity index after Hellinger transformation of the data set . The analysis of similarity (ANOSIM) allowed testing the grouping of samples according to sampling date, season, or algal diet.