Can Olympia oysters make a comeback in Quilcene Bay?

Kirk Boxleitner
Posted 5/23/18

Many hands sought to make relatively light work out of an ambitious undertaking May 16 in Quilcene, as roughly a dozen volunteers assembled at the end of Linger Longer Road to take stock of the …

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Can Olympia oysters make a comeback in Quilcene Bay?


Many hands sought to make relatively light work out of an ambitious undertaking May 16 in Quilcene, as roughly a dozen volunteers assembled at the end of Linger Longer Road to take stock of the area’s remaining Olympia oyster population.

Before over-harvesting and pulp mill pollution forced Pacific Northwest oyster farmers to turn to the Pacific oysters of Japan as a substitute, Olympia oysters were the dominant native species, and various environmental and oyster farming-affiliated groups are keen to see the molluscs make a comeback.

Brian Allen, a marine ecologist with the Puget Sound Restoration Fund (PSRF), instructed the volunteers who arrived at the Quilcene Boat Ramp to record not only where they found any Olympia oysters as the tide went out, but also where the oysters tend to aggregate.

“I take digital pictures with GPS notes,” Allen said. “The important thing is to identify the locations well enough that other people can return to those places and confirm your findings, and eventually cobble this all together into one big map image. Where is the oysters’ largest presence? Where do you stop encountering them? This is what we need to know.”

Allen and Brady Blake, a shellfish biologist with the state of Washington, advised volunteers to check underneath rocks or pieces of wood, since oysters prefer “thermal refuges” that avoid going to extremes of hot or cool.

“Bear in mind, you’re going to find the oysters not in the places they’ve sought out, but in the places they’ve managed to survive,” Allen said. “They need structures to which they can attach themselves.”

Chris Eardley, the Puget Sound shellfish policy coordinator for the state Department of Fish and Wildlife, agreed with Allen and Blake that the sound has become “more favorable” to Olympia oysters in recent years than it was during the early part of the 20th century, as most of the “major stressors” which impeded the species’ survival are “no longer in play,” in Blake’s words.

“But in order for us to develop a plan to restore the species, we need to know what the state of the species looks like right now,” Eardley said, citing the potential impacts of factors such as shoreline ownership and the presence of predator species. 

PSRF executive director Betsy Peabody recalled that Quilcene Bay alone once hosted roughly 100 acres of “solid” Olympia oyster beds.

“They were the dominant life form,” Peabody said. “So, the question becomes, to what extent are they still here, and where?”

According to Peabody, the PSRF, which was founded in 1997, was looking for restoration programs to which it could “add value” when the state Department of Fish and Wildlife released its initial Olympia oyster stock rebuilding plan in 1998.

“We love collaborating with tribes, industry, government, researchers and community groups,” Peabody said, outlining PSRF’s mission to rebuild Olympia oyster populations and restore native oyster habitat at 19 priority locations throughout Puget Sound. “Oyster beds are themselves a biogenic habitat in that they’re a living organism which provides a natural habitat for other species.”

Among PSRF’s tribal partners are the Jamestown S’Klallam Tribe, represented during the May 16 outing by environmental biologist Neil Harrington, who would return to the site two days later for the tribe’s yearly monitoring of its own test plots on the Quilcene tidelands.

“These test plots are areas where we spread oyster shell with young Olympia oysters in 2016, and again in 2017, to gauge if this area would be suitable for a larger project,” Harrington said. “If this area does have a good survival rate, we’ll be looking to expand and create a larger oyster bed. If the survival rate is low, we’ll have to look for a new area to create a bed in this general area of the Quilcene Bay.”

Harrington told The Leader after the May 16 outing that the volunteers found “significant wild populations” in Quilcene Bay.

“So they are persisting, albeit not so much as beds of oysters, but in more scattered populations” he said.

Cheryl Lowe, water programs coordinator with the Jefferson County Marine Resources Committee and the Washington State University Extension Office in Port Hadlock, reiterated Peabody and Allen’s points about Olympia oyster beds growing together to create overlapping, layered structures that provide shelter, habitat and food for other marine species, much like eelgrass or kelp beds.

“Restoring Olympia oyster beds makes Puget Sound more resilient as conditions continue to change,” Lowe said.

Lowe acknowledged that native oysters tend to grow slower and smaller than the non-native Pacific oysters, but she touted the Olympia oysters’ superior resiliency in the face of ocean acidification.

“Perhaps it’s because they’ve evolved and adapted in the Pacific Northwest, from Baja California to Southeast Alaska, where marine conditions have changed over time,” Lowe said. “I’ve read several articles about Olympia oysters being ‘wiped out,’ which is not quite true. Large beds of Olympia oysters are very uncommon in much of their historic range, but small numbers have managed to hold on in scattered areas.”

Lowe confirmed Harrington’s account that the May 16 survey in Quilcene located Olympia oysters in small clusters or singles attached to rocks or Pacific oyster shells along the many small seeps and narrow strips of suitable habitat on those shores.

“They’re around, but not providing the ecological services they could offer if they were growing in denser, larger beds,” Lowe said. “It’s like scattered trees planted in parks and gardens, versus a forest.”

Lowe welcomes the involvement of private tidelands landowners in restoration efforts, so long as the property owners can ensure they have suitable habitat and get seeded cultch genotypes from their part of Puget Sound. 

Cultch is the mass of stones, broken shells and grit from which an oyster bed is formed.

“For example, southern Hood Canal stock is very different than Sequim Bay or Discovery Bay stock, since each sub-population has adapted to local conditions,” Lowe said. 

She added that PSRF is growing several different genotypes in its hatchery.

“Private shellfish growers like Taylor Shellfish have also been donating seeded Olympia oyster cultch for the test plots that we looked at (May 18),” she said.