Eugene weekly., November 16, 2017, Page 11, Image 11

TRAVIS WILLIAMS OF
WILLAMETTE RIVERKEEPER
SEARCHES FOR MUSSELS
NEAR SKINNER BUTTE
PHOTO BY CAMILLA MORTENSEN
Mussel Mania
The plight of Oregon’s freshwater mussels
BY CAMILLA MORTENSEN
S
tanding chest deep in the chilly waters
of the Willamette River, Travis Williams
of Willamette Riverkeeper scans the
water for mussels. The flow is high on
a cold October day, and as I gingerly
climb down the muddy bank and into
the waters beside him, I too look for the
dark shells Williams tells me are there, beneath the surface.
Thinking back to various floats I’ve done on the
Willamette, I know I’ve seen mussel shells. I just never
thought about them. On some level, I assumed that the
bivalve remnants had somehow crept into the waters from
the Pacific Ocean.
And that’s the thing with freshwater mussels. They tend
to go unnoticed, unregarded and underappreciated.
We are next to Skinner Butte, the only pair of people in
dry suits planning to plunge into the water, at a spot where
Williams says he’s seen a bed of mussels in the past. It’s a
good spot for them, he tells me — the flows aren’t too fast
here and the riverbed is right for them.
Unfortunately, the water is too high and murky today to
see any shells, and I turn down Williams’ offer to follow
his example and plunge my face into the cold water and
snorkel around.
I admit that I’m reluctant not only because it’s cold, but
also because I worry about the Willamette being less than
clean as it flows through town. I know I’m not alone in
that fear, and that is one reason we need to learn to love
freshwater mussels: They clean the river.
Before we part, Williams hands me a slim booklet, a field
guide called Freshwater Mussels of the Pacific Northwest,
put out by U.S. Fish and Wildlife Service and the Xerces
Society for Invertebrate Conservation, among others. As I
read it later, in the warmth of my office, I note that the word
“unknown” comes up again and again in reference to which
fish host the mussels in their larval stage, historical data and
the long-term effects of the loss of native fish.
Despite being small, simple creatures, there is much we
don’t know about the freshwater mussels of the West.
Mussels face the same challenges that salmon and other
more charismatic species face, such as climate change,
invasive species and dams. At the same time mussels are a
key element in river health. Scientists and river advocates
have been delving into mussels, where they are, how they
survive and how to bring them back.
The Confederated Tribes of the Umatilla have taken
that one step further as they look at mussels’ key role in the
ecosystem as a tribal “First Food.”
Flexing the Willamette’s Mussels
Williams really began thinking about mussels in 2014
after the Willamette Riverkeeper group he heads up began
to acquire Norwood Island, at the confluence of the Long
Tom River and the Willamette, north of Corvallis. The
$70,000 purchase will be completed this year. Williams
discovered a massive bed of mussels in a river channel
along the island. “I looked down,” he says, “and the entire
channel was littered with mussels. It blew my mind.”
This past summer Williams snorkeled 120 miles of the
river, spotting other mussel beds along the way, including
the one we tried to look at in Eugene.
Some of the Norwood mussels were quite large. As it
turns out, freshwater mussels can be very long-lived. One
species native to Oregon and the primary one found in the
channel, the Western pearlshell (Margaritifera falcata) can
live more than 100 years, making it one of the longest-
lived animals.
Oregon is also home to the Western ridged mussel
(Gonidea angulata), which lives 20 to 30 years, and the
shorter-lived Oregon floater (Anodonta oregonensis) as
well as other floater species. Floaters tend to live 10 to 15
years.
All of these are among the eight species found in the
eugeneweekly.com • November 16, 2017
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