Ecological periodic tables for benthic macrofaunal usage of estuarine habitats: Insights from a case study in Tillamook Bay, Oregon, USA

This study validates the ecological relevance of estuarine habitat types to the benthic macrofaunal community and, together with previous similar studies, suggests they can serve as elements in ecological periodic tables of benthic macrofaunal usage in the bioregion. We compared benthic macrofaunal Bray–Curtis similarity and the means of eight benthic macrofaunal community measures across seven habitat types in Tillamook Bay, Oregon, USA: intertidal eelgrass (Zostera marina), dwarf eelgrass (Zostera japonica), oyster (Crassostrea gigas) ground culture, burrowing mud shrimp (Upogebia pugettensis), burrowing ghost shrimp (Neotrypaea californiensis), sand and subtidal. Benthic macrofaunal Bray–Curtis similarity differed among all the habitats except ghost shrimp and sand. The habitat rank order on mean benthic macrofaunal species richness, abundance and biomass was dwarf eelgrass ≈ oyster ≥ mud shrimp ≈ eelgrass > sand ≈ ghost shrimp ≈ subtidal. The benthic macrofaunal habitat usage pattern in Tillamook Bay was, with a few exceptions, similar to that in two other US Pacific Northwest estuaries. The exceptions indicate variants of eelgrass and ghost shrimp habitat that differ in benthic macrofaunal usage perhaps due to differences in the coarseness of the sand fraction of the sediments in which they live. The similarities indicate periodic benthic macrofaunal usage patterns across the other habitat types extend over a wider geographic scale and range of environmental conditions than previously known.