Poulsbo oysters used to rebuild populations elsewhere

“These will be the parents for the oysters aimed at central (Puget) Sound.”

POULSBO — Poulsbo has a lot to offer Puget Sound: A tourist destination. A family-friendly community. An attractive downtown. And, of course, oysters.

“We are going to use the oysters that we collect in Liberty Bay to produce seed to support restoration in other parts of the central (Puget) Sound,” said Betsy Peabody of the Puget Sound Restoration Fund.

The organization recently sent a team to the Poulsbo shoreline to collect approximately 1,000 oysters that will be taken to a shellfish hatchery in Manchester. After producing sufficient quantities of young oysters, they will be brought back to their home in Liberty Bay.

The produced oysters will be placed on tidelands throughout central Puget Sound in 2016 with the aim of increasing the region’s native oyster population.

The team sent to Liberty Bay on March 23 was led by Derek King, program technician with the Puget Sound Restoration Fund. His team, a duo, were two students from Eagle Harbor High School on Bainbridge Island: junior Meg Brown and senior Emily Rogers.

The three spent the afternoon walking the muddy shoreline at low tide near American Legion Park, picking up oysters and dropping them in a bucket. As they searched, King gave the students a background of the oysters and the purpose of the collection effort — that the oysters they were collecting were Olympia oysters, the region’s native variety that has suffered an extreme loss of population and habitat throughout Puget Sound.

“These will be the parents for the oysters aimed at central Sound,” King said.

“In the last 100 years, we’ve decimated the Olympia oysters,” he said. “We’re at about 4 percent of historic numbers. Historically you could walk down any beach in the Puget Sound and you would be walking on them, they’d be so dense. Now, it’s mostly mud.”

King said the Olympia oyster’s demise is due to a combination of factors — from sedimentation, pollution, and oyster companies failing to care for the habitat they harvested.

By taking oysters and not leaving the shells, dead shells are removed from the tideland, which discourages oyster larvae from settling and growing. That habitat has decreased over time.

“If it’s just mud or sand, it’s not going to make it,” King said.

And just why are the oysters so important that the fund is putting so much effort into their restoration?

“A big problem is that people look out (at the water) and say, ‘Oh, it’s functioning because it looks pretty. I don’t see oil and it’s not on fire, it must be fine,’” King said. “When really, there are some major things happening, like key native species that serve this ecosystem are missing.

“When you have Olympia oysters, you don’t just see Olympia oysters,” he said. “You see lots of micro and macro invertebrates, and tons of life that are drawn to the (habitat).”

But oysters do more than build marine communities.

“Oysters are filter feeders. Each one of these oysters can filter up to 40 or more gallons of water a day,” King said. “When you are talking about a bay that used to have filter feeding animals, and now doesn’t, you then start to hear about nutrient pollution, which is excess nitrogen and phosphorus entering the system from our waste, our pets’ waste, our agriculture’s waste.”

That nutrient pollution can fuel other problems such as excess algae growth.

“When you have a healthy ecosystem and you have a ton of oysters out there, the water is getting filtered,” he said. “When you have millions of oysters out there, doing 40 gallons a day, they are making an impact.”

Liberty Bay wasn’t always an oyster haven, and it is still a ways to go to become one. The restoration fund began Liberty Bay’s oyster recovery in 1999.

“We spread shells to provide settlement structure for larvae that were naturally present in Liberty Bay,” Peabody said of about 20 acres in Liberty Bay and Dogfish Bay. “As the result of the successful restoration efforts on those 20 acres, the restoration in Liberty Bay has expanded. There’s lots of little pockets in Liberty Bay that have Olympia oyster populations.

“One of the reasons we do this is that we are trying to accelerate the recovery of these populations,” she said. “It helps preserve heritage and culture. This is the oyster on which Washington state’s commercial shellfishing industry was established. It’s the oyster that Tribes gathered and ate for years.”