Bivalves
Molluscs in the Class Bivalvia feed on phytoplankton and detrital particles suspended in the water column, serving as a key trophic link between microscopic primary producers and higher consumers. Epibenthic bivalves can function as ecosystem engineers through the provision of hard substrate and three-dimensional biogenic structure, while infaunal bivalves can function as engineers through physical alteration of soft substrate habitats. Numerous native and non-native species of bivalves occur in Puget Sound, including important aquaculture species such as Pacific oysters (Crassostrea gigas), non-native invasive species such as the purple varnish clam (Nutallia obscurata), and species targeted in recreational fisheries (e.g., nativelittleneck clams and non-native Manila clams). The native geoduck clam, Panopea generosa, is valued as a commercially-fished species and as an aquaculture species. The native Olympia oyster, Ostrea lurida (also known as Ostreola conchaphila) currently is a restoration target in Puget Sound, having been depleted through human activities in the last century.
OVERVIEW
Bivalves in Puget Sound
Many types of bivalves, both native and non-native, flourish in Puget Sound. These species are a crucial part of the Puget Sound ecosystem and are also important for commercial fisheries.
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![Bay Mussels (Mytilus trossulus) on Edmonds Ferry Dock. Photo [cropped]: brewbooks (CC BY-SA 2.0) https://www.flickr.com/photos/brewbooks/8840874065 Bay Mussels (Mytilus trossulus) on Edmonds Ferry Dock. Photo [cropped]: brewbooks (CC BY-SA 2.0) https://www.flickr.com/photos/brewbooks/8840874065](https://www.eopugetsound.org/sites/default/files/styles/scale_width_285/public/topical_article/images/8840874065_da3b29ce56_crop_1200_0.jpg?itok=f8GftDPu)
Bay mussels in Puget Sound show traces of oxycodone
State agencies tracking pollution levels in Puget Sound have discovered traces of oxycodone in the tissues of native bay mussels (Mytilus trossulus) from Seattle and Bremerton area harbors. The findings were presented at the 2018 Salish Sea Ecosystem Conference in Seattle.

2016 Salish Sea Toxics Monitoring Review: A Selection of Research
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Puget Sound Ecosystem Monitoring Program
The Puget Sound Ecosystem Monitoring Program (PSEMP) is an independent program established by state and federal statute to monitor environmental conditions in Puget Sound.

Salish Sea snapshots: Invasive species and human health
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Clam hunger
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Reestablishing Olympia oyster populations in Puget Sound, Washington
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Gifts from the sea: shellfish as an ecosystem service
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Native shellfish in nearshore ecosystems of Puget Sound
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Ancient clam gardens of the Northwest Coast of North America
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Effects of geoduck aquaculture on the environment—a synthesis of current knowledge
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