Native oyster plan urged by working group

08/07/2019

The only native oyster species found today on the Pacific coast, Ostrea lurida, is the subject of a new restoration effort on Tomales Bay. 

Last August, the Greater Farallones National Marine Sanctuary’s advisory council established a working group dedicated to developing recommendations to restore the species, not only to ensure its long-term survival despite a changing climate but also to help revitalize the bay’s ecosystem.

The working group, which included researchers and planners from a host of local and regional agencies, will present its suggestions to the advisory council in Half Moon Bay on Aug. 15. The public has until this Friday, Aug. 9 to submit comments on a preliminary report the group released in June.  

According to that report, the working group primarily seeks to rehabilitate the species, which has declined in Tomales Bay along with increased sediment that covers its preferred rocky habitat, among other factors. 

“Restoration of a sustainable, resilient Tomales Bay native oyster—Ostrea lurida—population will provide biotic and abiotic benefits,” the report states. “This nearshore and intertidal foundation species will enhance ecosystem function by providing food and refuge for birds, fish and invertebrates. The oyster population will enhance ecosystem services that may contribute to coastal protection via oyster reefs that can attenuate wave energy and reduce the rate of coastal erosion.”

The recommendations first outline the need for more research. The group suggested that the Bodega Marine Lab, operated by the University of California, Davis, analyze all of the existing data on the native oyster. 

The group also recommended that the lab, along with the National Park Service and the Greater Farallones National Marine Sanctuary, create a map of the bay that highlights the limiting factors for the oyster’s growth. In partnership with Hog Island Oyster Company, which also sent a representative to the working group, those same agencies might also conduct a habitat assessment. 

According to the report, that combined data would help inform the development of a 10-year strategic restoration, a possible project of the park service, the sanctuary and California State Parks. Given the number of agencies with jurisdictional authority over the bay, the working group recommended developing an interagency approval process to streamline permitting. 

The report’s primary recommendation was for the sanctuary and the park service to implement and monitor a pilot restoration, beginning next year, in six locations in the bay, including off both the eastern and western shores. Following an evaluation at each site, the group proposed that beginning in 2027, those agencies implement a larger-scale restoration to ensure that the Ostrea lurida population is sustainable over time.  

Other recommendations include monitoring sediment dynamics, collecting data on the recreational use of the bay, studying the interaction between the native oyster species, eelgrass and other species and the role of the oyster in providing living shoreline benefits. 

A hearty education program, designed to inform recreationists and fishermen about the species and any potential recreation projects, was also proposed. 

Dr. Gary Fleener, an ecologist who has worked for Hog Island Oyster Company for the past two years and participated in the working group, said the company is excited to help with the effort. One possibility, which the Bodega lab may help the company explore, is farming the native oyster species. Hog Island already has permits to do so, but the species is more difficult to cultivate: it doesn’t like to be handled and it takes up to three years to grow to full size. 

Hog Island co-owner Terry Sawyer said the native oyster—found from Alaska to Baja and farmed in some places—has a strong flavor: almost metallic, but also sweet and delicious. 

His company is not only driven by profits, however; looking at the ecosystem as a whole is an essential part of its mission, Mr. Sawyer said. He explained that currently, native oysters grow in the low intertidal zone as opposed to the middle to upper tidal zone, where the bay’s farmed oysters grow. 

“The physical presence we have—we are out there every day, practically—could be beneficial for other species as well, just for monitoring purposes,” Mr. Sawyer said. “Considering the possibility of sample areas dedicated to the success of this organism, we are very supportive of that as well. We are very introspective about our impacts.” 

 

The Tomales Bay Native Oyster Restoration Working Group’s recommendations can be found at farallones.noaa.gov/manage/sac_meetings.html. Written comments can be sent to alayne.chappell@noaa.gov or submitted in person at the advisory council meeting on Aug. 15 at the Half Moon Bay Yacht Club.