Marine Intertidal Gravel: Semi-Protected

More protected gravel beaches contain more sand, are more stable and consequently have higher biological diversity.

Diagnostic Species

The isopod Exosphaeroma inornata (= media), and the polychaete Hemipodus borealis.

Common Associations

The amphipod Paramoera mohri, the isopod Excirolana kincaidi, and the polychaete Owenia fusiformis.  Areas with higher proportions of sand will contain various clam species such as Transennella and Protothaca staminea.  Seines contain three species of Cancer crabs, Crangon alaskensis, and Pandalus spp.  Fishes include shiner perch, juvenile English sole, starry flounder, and padded, buffalo, and staghorn sculpins.

Sites Surveyed

Beckett Point in Discovery Bay.


Nyblade, 1979a,b; Cross et al., 1978.