West Point Beach at Discovery Park, Seattle
This page describes the beach and its marine life. For information about the park, its recreational amenities, directions and open hours, please visit City of Seattle's Discovery Park page (external). Site DescriptionThis beach is located in Discovery Park on both the north and south sides of the West Point Wastewater Treatment Plant. The north and south beaches are very different and are discussed separately. South BeachThe gradient of this beach is very low. When the tide is at MLLW, more than a quarter mile of beach is exposed. Most of the beach lies at the base of a sand/clay bluff from which the beach material is eroded; consequently, the beach is very sandy. At about 0 feet, a large eelgrass bed begins. Closer to the shore, there are a few boulders and some cobbles. The sand forms a layer about 6 feet thick over cobbles and crushed rock used to build sludge lagoons, which have been dredged and dismantled. North Beach The beach here is more typical of the majority of the beaches in this region. On the point, the beach is relatively steep and is composed mainly of cobbles and gravel. However, as one proceeds east, the slope lessens and the beach becomes a flat composed of fine gravel and coarse sand. The upper beach here is stabilized with riprap. Near the flat area to the east, there is a deposit of concrete slabs that does not appear to have been disturbed for many years. Access to the beach has been limited to some extent for many years either by Metro or the Seattle City Parks Department. Invertebrates South BeachThirteen (13) species of invertebrates were found here. The horse clams seem to favor this kind of sandy environment over gravel. Since there is not much hard substrate for plants and animals to use for attachment, the diversity on this beach is relatively low. The boulders are colonized by barnacles, among which a few animals such as snails, chitons, colonial anemones and decorator crabs find shelter. The eelgrass bed is inhabited by Dungeness crabs, moon snails, cockles and burrowing anemones. Sea lemons, shaggy mice, and two sea slugs were also found here. North BeachThe invertebrate population was surveyed and 29 species of invertebrates were found here, the ninth highest of the beaches surveyed. The population was particularly rich on and under the concrete slabs. As on most beaches, the mollusks and crustaceans were the best represented groups with fifteen and twelve species, respectively. The anemones seem to be well represented as well.
| SnailsNorth |
South |
| Sitka PeriwinkleLitorina sitchana |
x |
| Checkered Periwinkle Litorina scutulata |
x |
| Direwhelk Searlesia direa x |
|
| Chitons |
| Lined Chiton Tonicella lineata |
x |
| Mossy Chiton Mopalia mucosa |
x |
| Hairy Chiton Mopalia ciliata |
x |
| Bivalves |
| Native Littleneck Protothaca staminea x |
x |
| Manila Clam Tapes japonica x |
|
| Butter Clam Saxidomus gigantea x |
x |
| Cockle Clinocardium nutalli x |
x |
| Softshell Mya arenaria |
x |
| Horse Clam Tresus sp. x |
x |
| Sand Clam Macoma secta |
x |
| Inconspicuous Macoma Macoma inconspicua |
x |
| Bay Mussel Mytilus edulis |
x |
| Jingle Shell Posodesmus cepio |
x |
| Sea Slugs |
| Sea Lemon Archidoris monterreyensis x |
|
| Shaggy mouse Aeolidia papillosa x |
|
| Sea Stars |
| Mottled Star Evasterias troschelli |
x |
| Purple Star Pisaster ochraceus |
x |
| Barnacles |
| Acorn Barnacle Balanus glandula |
x |
| Small Acorn Barnacle Chthanalus dalli |
x |
| Thatched Barnacle Balanus cariosus x |
x |
| Crabs |
| Purple Shore Crab Hemigrapsus nudus |
x |
| Green Shore Crab Hemigrapsus oregonensis |
x |
| Black Clawed Crab Lophopanopeus bellus x |
x |
| Dungeness crab Cancer magister x |
x |
| Red rock crab Cancer productus |
x |
| Pygmy Rock Crab Cancer oregonensis |
x |
| Graceful Crab Cancer gracilis |
x |
| Porcelain Crabs |
| Pubescent porcelain crab Pachycheles pubescens |
x |
| Flattop crab Petrolisthes eriomerus |
x |
| Isopods |
| Brown Isopod Idotea urotoma x |
|
| Oregon Pillbug Exosphaerona orgonensis x |
| ClamsNo formal clam survey was conducted, because volunteers would have gotten in the way of construction and landscaping activities at both the north and south beaches. No well defined clam band was observed on the south beach. The clam band on the north beach was very well defined. Seaweed There was no formal seaweed survey here, but Sargassum muticum was seen to be invading the area. OtherHerons were common. A bald eagle was observed eating a fish it had caught and dragged onto the beach.
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