Comparisons of bivalve assemblages (abundance of each species) between (A) decadal time periods and (B) four southern California estuaries.

Bivalve data were averaged by year for each estuary (within each study) and pooled into four decadal time periods. Shown are ANOSIM pairwise p values, and both the % similarity and the species contributing ≥ 5% of the variability between groups from the SIMPER analyses. ANOSIM Global test statistics are: (A) Global R = 0.43, P = 0.001, and (B) Global R = 0.63, P = 0.001.