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Internships with PSI

Intern or volunteer on one of PSI's research projects or outreach campaigns.


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The man with a plan

PSI researcher, Andy Suhrbier helps shellfish growers adapt to changing ocean conditions.

Mussel Power

Nutrient Bioextraction: Can shellfish farming improve water quality?

Shellfish are nature's water filters--one large mussel can filter upwards of 10 gallons of water each day

Nutrient bioextraction is "an environmental management strategy by which nutrients are removed from an aquatic ecosystem through the harvest of enhanced biological production, including the aquaculture of suspension-feeding shellfish or algae" Nutrient removal by shellfish, which are then harvested from the system, has the potential to help address environmental issues in waterbodies including excess inputs of nutrients (eutrophication), low dissolved oxygen, reduced light availability and impacts on eelgrass, harmful algal blooms, and increases in incidence of paralytic shellfish poisoning (PSP). On average, a harvested mussel contains: 0.8 –1.2 % Nitrogen (N) and 0.06 –0.08 % Phosphorous (P). Removal of enhanced biomass (shellfish or algae) from impaired waters can combat problems associated with excess nutrients (eutrophication) while supporting the local economy by providing product for animal feed or compost. PSI and the Puget Sound Restoration Fund are beginning to investigate the potential use of mussels for nutrient mitigation in several locations in Puget Sound; Vashon Island, Tacoma, and Olympia’s Budd Inlet.

With these projects, PSI and partner organizations aim to demonstrate a creative strategy to reduce anthropogenic nutrient loads and support habitat renewal through the establishment of cost-effective, community-based bioextraction programs. These projects involve community members in the cultivation of a local species of bay mussel to quantify the nutrient sequestering abilities of this process and to demonstrate market-based mechanisms for removing and recycling excess nutrients (Nitrogen and Phosphorus) through the development of a high-value compost product. At the same time, these projects aim to increase public awareness of water quality issues including bacterial pollution, eutrophication, and harmful algal blooms and offer activities that empower citizens to envision a swimmable, fishable Puget Sound. Printable 1-page Summary

Detailed reports, including an executive summary, are available:

Surf to Turf Mussel Compost: Removing and Recycling Nutrients from Budd Inlet - Final Report (8 MB PDF, 5/2017)

Appendices (2.46 MB PDF, 5/2017)

Executive Summary (5/2017)

Shellfish at Work – Reducing Nutrient Pollution in the Budd Inlet Watershed - Final Report (2.2 MB PDF, 12/2014)

Appendices (4.4 MB PDF)

Bioextraction Poster

Scraping Mussels

PSI Biologists Mary and Aimee scrape mussels from the Port of Olympia pier for nutrient bioextraction and composting trials in May 2016.

These projects were made possible through support from the Russell Family Foundation, King County, the Washington Department of Ecology, and the U.S. Environmental Protection Agency (EPA).

Mussel Power Photo

Mussel Biodiversity

Bioextraction in Action:

In spring 2015 bioextraction trials performed in 2013/2014 were replicated in Budd Inlet at Swanton Boatworks and West Bay Marina, removing over 5,000 pounds of mussels and creating 6 cubic yards of nutrient rich compost. In spring 2016, PSI tested the feasbility of removing mussels from pre-existing structures in Budd Inlet for nutirent bioextraction and compost creation.

Mussel Power Photo

Mussel Power Photo