News

Seeding a cleaner harbor

Cara Cruickshank (right) of  the Natural Landscapes Project discusses “oyster gardening” with volunteer Gwendolyn Harper, 6, along Eagle Harbor’s shore Saturday. Baskets loaded with juvenile oysters were installed by over a dozen volunteers along marina moorings and private piers to help filter and clean the harbor’s waters. The first project of its kind in the region, organizers hope the mature oysters will filter as much as 5 million gallons of water per day. - Julie Busch photo
Cara Cruickshank (right) of the Natural Landscapes Project discusses “oyster gardening” with volunteer Gwendolyn Harper, 6, along Eagle Harbor’s shore Saturday. Baskets loaded with juvenile oysters were installed by over a dozen volunteers along marina moorings and private piers to help filter and clean the harbor’s waters. The first project of its kind in the region, organizers hope the mature oysters will filter as much as 5 million gallons of water per day.
— image credit: Julie Busch photo

The introduction of oysters should boost water quality, island conservationists say.

Cara Cruickshank eases a basket into Eagle Harbor, taking care not to jostle the 500 infant oysters inside.

She sets them at a particular depth – out of reach of predators but low enough to foster the oysters’ full development under the harbor’s fluctuating tides.

“These oysters are a natural solution to a big problem in our harbor,” she said as briny water dripped from her hands. “When I heard about this, I said, ‘Wow, creatures can help us mitigate our own waste.’”

With the oysters Cruickshank is planting the seeds of a project that will eventually grow into what may be the harbor’s best hope for combating pollution and the rising rates of human waste trickling from the shore.

Cruickshank, who serves as co-director of the Natural Landscapes Project, rallied over a dozen volunteers Saturday to help instal about 150 “oyster gardens” from marina moorings and private docks along the harbor’s shore.

The project is believed the first of its kind in the Puget Sound, according to Cruickshank, who teamed with the city’s Shoreline Stewardship program and the Bainbridge-based Puget Sound Restoration Fund to obtain about $27,000 in state, city and private grants.

“This really is a pilot project,” she said. “They’ve done it in Chesapeake Bay, but we have different conditions and water temperatures so we have to watch it closely.”

Once the 100,000 oysters planted on Saturday reach maturity in two to three years, they’ll filter about 5 million gallons of water a day.

Along with the water, the oysters will filter industrial toxins and nutrients from chemical fertilizers and septic systems.

These nutrients are blamed for feeding the excessive growth of phyto-plankton and seaweed that block sunlight from reaching bottom-dwelling plants, such as the eelgrass that formerly grew in vast underwater meadows.

“In 1997, extensive eelgrass meadows were documented in the inner-harbor,” said city shoreline planner Peter Namtvedt Best, who helped initiate the oyster gardening project. “In 2004, we found none.”

As eelgrass has declined, so have salmon, which use the plant as habitat while foraging for food, according to Best.

“Algae blooms” caused by unnaturally high doses of nutrients also depletes oxygen from the water, suffocating marine life and creating “dead zones.” like those documented in Hood Canal.

“I’ve been exposed to this algae problem in the canal,” said city Harbor Commissioner Bob Selzler, who volunteered a boat and helped install oyster gardens Saturday.

“When the algae dies, it sinks to the bottom and rots, sucking all the oxygen out of the water and kills fish. Our harbor’s similar to the canal, in that we don’t have (strong) tidal flow flushing things out.”

Selzler also donated the use of his shoreside barn to prepare the oyster baskets and their riggings last month.

“This has been fascinating,” he said. “I want to see the effects of introducing something so new and so simple as farming oysters to see how much it makes our water cleaner and clearer.”

The idea for the project was sparked by Best’s research into similar efforts in Chesapeake Bay, where Virginia and Maryland have spent tens of millions of dollars on oyster restoration efforts.

“They’d had successes there and the technique is now used widely in Massachusetts, North Carolina and all sorts of places,” Best said. “We got the idea to do this here by identifying problems in Eagle Harbor, where we see significant loss of eelgrass and important salmon habitat. It triggered us to do something about it.”

Scientists chose oysters for the Chesapeake project because of the animal’s superior filtering prowess.

Processing water at a rate of two to three times that of other shellfish, oyster beds serve as high-capacity sewage-treatment plants for the marine world.

“We really need that here because of all that waste running into the water,” said Cruickshank, who is working with the city on a series of studies to gauge the full impact of excess nutrients in the harbor.

But any longtime harbor-dweller doesn’t need a study to see evidence of dramatic change.

“It’s become a soup,” said Selzler. “You see it every summer now with the algae blooms that cover parts of the harbor.”

While the oysters may tackle some of the problem, Cruickshank admits the project isn’t the ultimate solution.

“We have to change the way we deal with our waste,” she said. “Preventing the cause is more important. We have to work at a policy level on that, and on a house-by-house level. We have to realize we’re fouling our own nest. Animals know better.”

That’s why Cruickshank hopes to involve more residents in the project and has enlisted the aid of high school students and a local Boy Scout troop to help hang oyster baskets and clean them over the next few years.

Harbormaster Tami Allen, who brought her 8-year-old daughter Alexina to volunteer on Saturday, said many adults may be set in their ways – but kids have a knack for absorbing new ways to protect the environment.

“Alexina loved it,” Allen said. “She said the little baby oysters were so cute and adopted about five of them. She wants to see how they grow when we check on them in the fall.

“I think other kids who do this may mention to their parents not to use fertilizers so they don’t end up undoing the work the kids did with the oyster gardens. They’ll be the ones to train their parents and be a part of the education that’s necessary in the long-term.”

*************

Pearls of wisdom

The “Oysters for Salmon” project is looking for more dock owners to host oyster garden baskets and volunteers to check and clean them on public marinas. The project also seeks donations to cover equipment costs. Call Cara Cruickshank, Natural Landscapes Project, at 842-4815 for more information.

We encourage an open exchange of ideas on this story's topic, but we ask you to follow our guidelines for respecting community standards. Personal attacks, inappropriate language, and off-topic comments may be removed, and comment privileges revoked, per our Terms of Use. Please see our FAQ if you have questions or concerns about using Facebook to comment.
blog comments powered by Disqus

Read the latest Green Edition

Browse the print edition page by page, including stories and ads.

Aug 29 edition online now. Browse the archives.