The persistence and stability of fish assemblages within eelgrass meadows (Zostera marina) on the Pacific coast of Canada

Abstract

The persistence and stability of fish assemblages found in 34 eelgrass (Zostera marina) meadows along the British Columbia coast was examined from 2004 to 2011. Assemblage persistence (nontrending species composition) and assemblage stability (constancy in abundance over time) were assessed using a time-lag regression method that tests for temporal turnover within short time series. Overall, 85% of the fish assemblages persisted, and 80% of the assemblages exhibited stability in abundance over the 8-year study. Environmental conditions in 33 of 34 meadows did not change substantially over the 8 years, and the low interannual variability may have contributed to the high persistence and stability of the fish assemblages. The lack of temporal turnover in relatively undisturbed eelgrass fish assemblage properties is a critical element for effective monitoring of coastal ecosystem integrity.