Olympia Oysters

David Hyde
08/19/2008

September has an "r" in it, making it the unofficial start of oyster season. Did you know most of the oysters you are likely to encounter on the half–shell are what scientists would normally call invasive species? The Olympia is the only oyster native to the west coast of North America. These days the wild oysters are hard to find on most Puget Sound beaches due to habitat loss, water pollution and over–harvest. Scientists are studying one of the last intact wild Olympia oyster reefs. It's on the northwest coast of Vancouver Island. KUOW's David Hyde reports in the second of our two–part series on oysters.

TRANSCRIPT

BRIAN KINGSET IS A CANADIAN SHELLFISH BIOLOGIST. HE'S WALKED NEARLY EVERY OYSTER BEACH IN BRITISH COLUMBIA. ABOUT 15 YEARS AGO, KINGSET WAS EXPLORING A NARROW INLET ON VANCOUVER ISLAND WHEN HE SAW OYSTER NIRVANA.

KINGSET: "In this particular area we're standing today, in Port Eliza, and just a very few other areas on the coast, we noted these really dense pockets of the native oyster, which is quite unusual because we actually surveyed several thousand beaches."

KINGSET IS STANDING ON THE EDGE OF A FRESHWATER STREAM, WITH TWO BLACK BEARS FEEDING NEARBY. DOZENS OF OLYMPIA OYSTERS GLISTEN IN THE MUD AT HIS BOOTS. THEY'RE GOLD–HUED AND TINY — ABOUT THE SIZE OF A 50–CENT COIN. AND THEY OCCUPY A SOLID BAND ON THIS COBBLY BEACH THAT STARTS JUST ABOVE THE EEL GRASS IN THE INLET. THE OLYPIA OYSTER WAS AT ONE TIME ABUNDANT ON THE WEST COAST. AND AN IMPORTANT FOOD SOURCE FOR COASTAL TRIBES.

KINGSET: "What is really important here is this is an animal that at the turn of the century — 1800s — had extensive distribution and really phenomenal biomass in many areas. From San Francisco all the way up to British Columbia that actually supported fisheries, that supported aquaculture, was in the straight of Georgia, where you very rarely find it now — in very large amounts — and then suddenly they're gone."

SO WHAT DECIMATED THE OLYMPIA OYSTERS? KINGSET SAYS IT STARTED WITH THE CALIFORNIA GOLD RUSH, WHEN COMMERCIAL HARVESTERS CLEARED ENTIRE BEACHES UP AND DOWN THE COAST.

KINGSET: "We know that over–fishing was a problem. We know that they're very sensitive to industrial pollution. That back from the 20s through the 40s we basically dumped effluents from things like black liquor pulp mills directly into the areas and so we really changed the chemistry and had this anthropogenic impact."

BUT THE OYSTER POPULATION IN THIS INLET ON VANCOUVER ISLAND IS SO ROBUST IT'S DRAWN SCIENTISTS FROM ALL OVER THE U.S. AND CANADA. RESEARCHERS SAY THAT UNDERSTANDING THESE INTACT WILD BEDS WILL HELP RESTORE OLYMPIA OYSTERS.

MARINE ECOLOGIST BRIAN ALLEN IS FROM OLYMPIA WASHINGTON. HE'S CALCULATING THE DENSITY OF THE OYSTERS IN THIS INLET. IN WASHINGTON STATE, OLYMPIA OYSTERS ARE FRAMED, AND IN SOME PLACES ABUNDANT. BUT WILD OLYMPIAS ARE SCARCE, AND THE REEFS ARE HARD TO FIND. ALLEN SAYS RESTORING THE WILD REEFS IS IMPORTANT TO THE HEALTH OF THE SOUND.

ALLEN: "It's important that Puget Sound not only looks nice but functions as an estuary. So, things like salmon that need to eat the very small zooplankton, where [do] those zooplankton exist? In the native oyster bed. Animals that come here are coming here to forage very often on things that are living in the structure that the oysters create."

THE SCIENTISTS ARE EXCITED BY THE NUMBERS OF OLYMPIA OYSTERS HERE: IT'S THE HIGHEST KNOWN DENSITY OF WILD OLYMPIA OYSTERS IN THE WORLD. THEY THINK THIS BED IS AS HEALTHY AS IT WAS HUNDREDS OF YEARS AGO. JOTH DAVIS IS A SHELLFISH BIOLOGIST:

DAVIS: "There are lots of oysters here. The question I have, and what I want to pass on to my children, is we need to try understand how and why these beds retain their longevity. What's the persistence? How do they persist? And that's going to be the ultimate challenge ... to figure that out."

DAVIS THINKS THE FRESH WATER FLOWING INTO THE INLET IS KEY. PRISTINE STREAMS ARE FLOWING DOWN FROM THE FOREST ABOVE ONTO THE OYSTER BEACH.

DAVIS: "There is nothing but trees and undisturbed watershed on this particular beach which is very rich in native oysters."

HYDE: "Do we see the same kind of thing in Puget Sound?"

DAVIS: "We don't because we have very few places like this in Puget Sound."

HYDE: "So, is clean fresh water important to oyster habitat everywhere, or not necessarily?"

DAVIS: "I'd have to think it's a critical component. These Olympia oysters are extremely sensitive to any kinds of contamination or pollution, and if we see that coming down in the streams, that would have a direct and detrimental impact on the oyster population itself."

IN WASHINGTON A GROUP CALLED THE PUGET SOUND OYSTER RESTORATION FUND IS TRYING TO BRING WILD OLYMPIAS BACK, DESPITE ONGOING POLLUTION PROBLEMS. THEY'RE SEEDING SITES WITH YOUNG OYSTERS AND SETTING DOWN OLD OYSTER SHELLS TO GIVE THE OLYMPIAS A PLACE TO GROW.

SCIENTISTS DON'T KNOW WHETHER THE OYSTERS CAN EVER BE RESTORED TO THEIR FORMER ABUNDANCE, BUT AT LEAST NOW THEY'VE GOT A BLUEPRINT TO SHOW THEM WHERE THEY WANT TO GO. FROM KUOW, I'M DAVID HYDE.

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