Mariculture in the Strait of Juan de Fuca

Finfish mariculture has existed in the Pacific Northwest for over thirty years, but for the past 15 years most effort has focused on culture of Atlantic salmon in protected, inshore pens. The Strait of Juan de Fuca (the "Strait") is a large area with sparse development in some regions and several apparent advantages for mariculture using offshore fish culture technology. The culture could be with salmon or marine fish using surface or submerged net pen systems. The latter are preferable for aesthetic considerations but in some locations the former may be more suitable for technical reasons.

This website provides an overview of pertinent hydrographic conditions and possible impacts of marine or salmonid finfish culture in the Strait for commercial harvest or marine fish stock rehabilitation.

Circulation studies, current and wave meter deployments, acoustic Doppler current profiles and phytoplankton assessments were conducted in three different regions distributed throughout the Strait near the southern shore.  Results were compared to existing inshore fish farms nearby and analyzed with a new simulation model that accounts for growth and metabolic oxygen demands of caged fish and the response of phytoplankton to nutrients and grazing.

Previously undetected and persistently lower sea surface temperatures were observed in satellite imagery for the central Strait region, especially during the summer and early fall.

Surface-layer water temperature was positively correlated with dissolved oxygen concentration during the same season. Accordingly, there could be significantly reduced dissolved oxygen content of surface waters of the central Strait during this period. Eastern and western areas of the Strait may be marginally better for fish culture on this account, depending on fish species cultured.

We conclude that low or no impact marine fish mariculture is technically feasible in the Strait. However, the high energy environment and challenging conditions will necessitate revised and novel management techniques to insure successful operations.

This study was sponsored in part by funding from NOAA Office of Oceanic and Atmospheric Research. Many individuals and organizations contributed in kind support, including the Washington Fish Growers Association and members, The Makah Tribal Nation, and several residents of Clallam County Washington who aided in field work and sampling.

Sunrise at Cypress Island

photo courtesy of Michael Womer, Anacortes, Washington

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