Explanations of patterns of intertidal diversity at regional scales


Mark A. Zacharias Land Use Coordination Office, Province of British Columbia, PO Box 9426, Stn. Prov. Govt., Victoria, BC, Canada, V8W 9V1. E-mail: mark.zacharias@gems6.gov.bc.ca



To test the hypothesis that the abiotic variables of salinity, temperature and fetch could explain patterns of intertidal species richness at regional scales (100–1000 s of km).


British Columbia, Canada.


Using a 180 station data set collected over 7° of latitude on bedrock shorelines, we used a combination of correlation, multiple regression and ordination to show that species richness was strongly related to fetch, salinity and temperature.


Results are consistent with the expected outcomes from the stability-time and intermediate disturbance hypotheses.

Main conclusions

Temperate intertidal environments are predominantly physically accomodated at regional scales. Implications for near-shore conservation are that the conservation of outer coast environments protects more species in a given area than inner coast environments.