Estuarine Subtidal Mud: Partly Enclosed, Shallow

These habitats, which are common in partly enclosed bays in Puget Sound, show little consistency in organisms.  This variability may be due to the range of physical parameters seen in these environments, especially in the degree of organic enrichment, pollution, and freshwater input.

Diagnostic Species

The bivalves Macoma nasuta and Mysella tumida, the polychaetes Armandia brevis, Glycinde picta, Terebellides stroemi, and Lumbrineris luti.

Common Associates

The bivalves Macoma inquinata, Protothaca tenerrima, and sometimes geoducks (Panope abrupta).  Polychaetes are abundant but variable, and include glycerids, cirratulids (especially Tharyx spp.), Nepthys spp., Eteone pacifica, Podarkeopsis brevipalpa, Schistomeringos moniloceras, and Capitella capitata.  Gastropods include the predatory Polinices lewisii. The sea cucumber Parastichopus californicus is seen in some bays. Amphipods include Aorides columbiae and Corophium salmonis. Many estuarine bays are used by river otters.  Fishes found here include Pacific tomcod, flounder, C-O sole, Pacific staghorn sculpin, and smelts.

Sites Surveyed

Commencement Bay, Shilshole Marina, Eld Inlet, Lynch Cove and Anderson Cove (Hood Canal), and Bellingham Bay.


Blaylock and Houghton, 1981; Wennekens, 1959; Milne, 1976; Harman et al., 1977 and unpubl. data; Chew, 1970; Webber, 1978; G.F. Smith, 1979; C. Staude unpubl. data.