Rocky intertidal areas in estuarine waters occur occasionally in the Puget Sound. Many of these could be classified as artificial substrata (riprap), while some are classified below as hardpan.  All tend to be in areas exposed to moderate waves or currents which keep silt from settling on the substratum and allow an epifauna to develop.  The plants and animals seen on these rocky substrata are largely a freshwater-tolerant subset of those seen on marine shores. These habitats are used at high tide by sculpins and probably other fishes.  Few complete surveys have been done on such sites.

Common Species

From high to low zones:  Littorina spp., Fucus gardneri, Balanus glandula, Mytilus edulis, ulvoids, Mopalia spp., Onchidella borealis, Iridaea splendens, Sargassum muticum, Leptasterias hexactis.

Sites Surveyed

Riprap at five sites in central Puget Sound, Kiket Island, Fidalgo Head.

Sources

Thom, 1978; Smith and Webber, 1978; Houghton, 1973; C. Staude unpubl. data.