Marine Subtidal Mixed-Fines: Moderate to Low Energy, Deep

-15 to 50 m: Sand, shell, pebbles

Diagnostic Species

The burrowing anemone Pachycerianthus fimbriatus.

Common Associates

Areas with finer substrata have beds of the sea pens Ptilosarcus gurneyi and Virgularia sp. and accompanying nudibranchs and asteroids. Other species include chaetopterid polychaetes, hydroids, the bivalves Saxidomus giganteus, Mya truncata, Protothaca staminea, Humilaria kennerlyi, Solen sicarius, Pododesmus cepio (on pebbles and shells); the scaphopod Dentalium rectius, the sea cucumbers Parastichopus californicus and Pentamera populifera, the crabs Cancer magister and Pugettia spp., the seastars Luidia foliolata, Pisaster brevispinus and Pycnopodia helianthoides, the cephalopods Octopus rubescens and Rossia pacifica.   Geoducks may occur in patches.  Pebbles at the shallower limit may have the red algae Stenogramme interrupta, Polyneura latissima, Nienburgia andersoniana and others.  Fish include rocksole, ratfish, dogfish, and tomcod.

Sites Surveyed

San Juan Islands.


R. Shimek, C. Simenstad unpubl. data.

-50 to 180 m: Sand and silt

Common Species

The bivalves Yoldia scissurata, Tellina carpenteri, Acila castrensis, Nucula tenuis, Macoma carlottensis, and Axinopsida serricata; the amphipod Rhepoxynius variatus, the polychaetes Magelona sp. and Sternaspis scutata.

Sites Surveyed

Strait of Juan de Fuca and outer coast.


Lie and Kelley, 1970; Lie and Kisker, 1970; R. Shime unpubl. data.