Freshwater mussels in 'danger of disappearing', says one tribal biologist - Tribe looks for budget money to list as 'endangered'

Freshwater mussels thrive in a portion of Bear Creek, which winds through Snohomish and King counties.

Wendy Walsh is trying to stop the decline of freshwater mussels in Bear Creek, which adjoins her property in Woodinville.

By Janice Podsada
Everett Herald Writer


In 1962, Wendy Walsh peered into Bear Creek, a salmon spawning creek near her new home, and saw a streambed covered in shaggy, brown rocks.

Unlike other rocks, these occasionally let loose a gurgle.

Freshwater mussels are foolers. Resembling rocks, they can live 100 years. During that time, they function as nature's water filtration system, ridding streams and rivers of contaminants such as bacteria and chemicals.

Today, mussels are rapidly disappearing from rivers and streams -- a loss that could reduce water quality and imperil fish habitat.

Tulalip Tribes biologist Kelly Toy has spent three years studying the decline of freshwater mussels in the Snohomish County area. Based on her research, the Tulalips recently requested that the western pearlshell, a freshwater mussel, be listed for protection under the Endangered Species Act.

Mussels online

For more information on Washington's three most common mussel species - western pearlshell (Margaritifera falcata), Oregon floaters (Anodonta oregonensis) and the western ridgemussel (Gonidea
angulata) - click on or and search for freshwater mussels.

State Department of Fish and Wildlife officials, who have the authority to list them, agree with the Tulalips' request.

"In the next go-round, 2004, we'll propose adding those freshwater mussels to our candidate list," said Derek Stinson, head of Fish and Wildlife's endangered species program.

Six species of native freshwater mussels exist statewide. Among them is the western pearlshell, scientific name Margaritifera falcata, which is in trouble, said Toy. She has been studying their decline in Bear Creek, which winds through King and Snohomish counties, and Battle Creek, on the Tulalip reservation.

An indicator species, mussels are a freshwater canary; they can droop or die if their habitat is fouled. Toy's research points to development, pollution and pesticides as major suspects in the mussels' demise.

A species recovery plan is not developed until after a listing occurs under the Endangered Species Act, Stinson said. So what specific measures might be taken to protect the freshwater mussels is anyone's guess at this point.

But if they are listed, their protected status could further tighten regulations governing new development along many streams and could shrink the list of chemicals and pesticides considered safe for industrial and private use. The listing could also affect the construction of Brightwater, King County's proposed third wastewater treatment plant, which is already beset by water-quality issues.

Under the Endangered Species Act, any activity causing harm to a protected species, including habitat destruction, is prohibited, except under exceptional circumstances.

"It probably won't have the same impact as the listing of the wild chinook," Stinson said. "But it could give increased attention to chemicals."

Not surprisingly, the same pollutants that harm salmon also harm mussels. In spite of a protective shell, they may be more sensitive to pollution than salmon or trout. They are, after all, housebound shut-ins, lacking the ability to move to a more hospitable part of the stream.

"I think you'll see them disappear before you'll see the fish disappear," Toy said.

There is state and federal money for salmon restoration, but finding additional money to protect freshwater mussels would be a challenge, Toy said.

In 1999, Snohomish County asked the state for $100 million in state and federal money for salmon restoration projects. Today, that kind of money isn't available in the state budget.

Mussels: Another layer of costs?

The 1999 decision to list wild chinook salmon as a threatened species got the attention of loggers, farmers and the home-building industry, and changed laws governing their operations.

The same thing could happen if the western pearlshell becomes a protected species. It all adds up to dollars, and who has to shell them out.

Protecting salmon has added substantially to the cost of development, said Sam Anderson, executive officer of the Master Builders Association of King and Snohomish County.

Builders are now required to construct storm water holding ponds, sometimes called detention ponds. "That's an expense," Anderson said. "It's added $10,000 to $20,000 to the cost per lot."

While the builder pays the initial price, the costs are passed on to the home buyer.

"This environmental stuff is expensive, and it's long term, and it's very unforgiving costwise," Anderson said.

Area farmers, especially dairy farmers, took a financial hit when chinook salmon were listed as threatened.

Another layer of regulations governing shellfish could further increase the cost of farming.

"The tragedy would be if we end up with a lot of farmers quitting -- their land going to the developers," said Dale Reiner, a Monroe farmer who raises beef cattle and Christmas trees along the Skykomish River.

Reiner said the 1999 listing increased farmers' costs and reduced the amount of land they could work.

"It has caused me not to plant and work the land within the (stream) buffer areas. I spend 20 percent of my time dealing with salmon issues," Reiner said.

Whether it's saving salmon or freshwater mussels, "its going to cost every farmer that has a riparian zone (land next to a river) some money and some land," he said.

"In the long run, protecting the streams is a good thing," said Reiner, a self-described advocate of clean streams and healthy salmon runs.

But, Reiner said, at some point, "society as a whole will have to help absorb some of our costs."

Another urban area grappling with mussel preservation costs is St. Louis.

In 2001, scale shell mussels -- freshwater mussels that dwell in the urban streams near St. Louis -- were listed as a federally endangered species, said Andy Roberts, a fish and wildlife biologist in Columbia, Mo. (Though Washington state doesn't have scale shell mussels, all mussels share the need for pollution-free water.)

Researchers, who haven't developed a recovery plan yet, aren't sure how St. Louis' regional activities will be affected. They do know that mussels have disappeared from polluted streams, Roberts said.

"We haven't narrowed down the chemicals, but contaminants are an issue," he said. "We are looking at ammonia, copper and chlorine, which can be found at sewer outfalls."

The Environmental Protection Agency sets standards governing the output of treated wastewater, Roberts said. "But we're unsure whether those current standards are enough to protect mussels."

Locally, a similar finding could potentially affect permitting and construction of the Brightwater sewage treatment plant. Little Bear Creek runs through the plant's preferred site near Highway 9 and 228th Street SE in unincorporated Snohomish County.

Mussels in St. Louis, the Puget Sound region and elsewhere haven't received the attention they deserve, even though they may be the "most imperiled group of animals in the country," Roberts said.

"They've only been in the spotlight for the last decade, so we're just getting started."

"They are declining rapidly. That should be a red flag for us as to the condition of our streams," he said.

What's eating freshwater mussels?

Studies indicate that elevated levels of heavy metals, including lead and cadmium that come from light industry, are stripping the calcium from mussels' shells and exposing the creatures to parasites and predators, said Ray Kinney, a researcher with the Siuslaw Watershed Council in Mapleton, Ore.

That's only one of the hazards that threaten their survival.

"These things are disappearing faster than we can figure out why," said Jayne Brim Box, a researcher with the U.S. Forest Service in Utah.

On Feb. 19, hundreds of biologists from all over the West gathered in Vancouver, Wash., to discuss the loss of freshwater mussels.

Walsh attended the conference. A registered nurse, she guards the mussel beds near her home in Woodinville as if they were her patients.

For the last 40 years, Walsh, 71, has watched the freshwater mussels disappear from Bear Creek. The biggest die-off occurred in 1990, when an avalanche of soil poured into the creek, smothering the mussel beds and killing 80 percent of them, Walsh said.

"It didn't have to happen," she said.

Upstream from the mussel beds, a developer failed to build a holding pond for storm water and silt. In preparing the lot for construction of an apartment complex, the developer scraped the soil into a mound, which was left at the site.

When a winter storm washed the soil into Bear Creek, the stream choked. A detention pond could have trapped the soil and released it slowly into the creek, but that didn't happen, Walsh said.

Instead, sediment clogged the mussels' gills, and they smothered. Their gills filter food and oxygen from the water.

Other hazards include the day-to-day discharge of garden chemicals into the creek, Walsh said.

"There is a line that divides Bear Creek," she said. "Above the line, we have mussels. Below, where the lawns come right down to the creek, there aren't any."

Stricter regulations covering the disposal of pesticides and sediment could help save the mussels, Tulalip biologist Toy said, along with increased stream buffers. "Some places only require 25- to 50-foot buffers," she said.

Biologists say even 100-foot buffers may not be enough.

Not just a regional issue, the loss of freshwater mussels is a national concern for biologists.

Of 297 freshwater mussel species found in the United States, 72 percent are considered endangered or threatened. And 69 species are listed for protection under the Endangered Species Act.

Their function, to filter toxins from the water, is critical, Toy said. "If you have an aquarium, you know -- you don't want to lose your filter feeders."

Their loss could not only affect water quality but further compromise threatened species such as wild chinook.

Like salmon and trout, mussels prefer cool streams with plenty of shade -- the same conditions that nurture juvenile salmon.

Recent evidence suggests that salmon and mussels may depend on each other for survival.

Juvenile pearlshell mussels cannot survive unless they attach themselves to the gills of a salmon or trout soon after they are born. During the attachment phase, they undergo a metamorphosis, leading to their ability to anchor themselves in the streambed.

If too few fish are around for the juvenile mussels to attach to, they go homeless and die. And with fewer mussels to filter out pollutants, the salmon and trout suffer the effects of decreased water quality.

Lean years lead to loss

Like a tree, a mussel's age can be determined by its growth rings. Each year, a mussel adds a ring. Lean years produce thin rings; bountiful years produce fat ones.

The last few decades have been lean.

In 1962, Walsh and her husband, a marine biologist, learned that mussels once filled local streams.

"Right after we bought this place at Bear Creek, all the zoologists came out and said the mussels used to be in all the creeks. Then they said, 'Isn't it too bad these creeks are losing their mussels.'"

For the next 30 years, Walsh urged biologists and zoologists to study the creek's vanishing mussels. But there were no takers.

"Kelly Toy was the first person who did the research," Walsh said.

Hopefully, Toy's findings haven't come too late.

"Whether or not listing is the best way to go, that's debatable," Walsh said. "Politically, that can be a hot potato. But the mussels need to be protected. They're dying off."


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