The Ballad of Ceratonova shasta

The Klamath River Basin, stretching across the border of Oregon and
California, has long been the spawning ground for multiple species of Pacific salmon and has a rich history of fishing. Historically, native tribes such as Yurok and Hoopa relied heavily on the river with its annual salmon runs, and continue their relationship with the river today. However, modern development of the river system has altered the ecosystem, as recreational fishing, agricultural irrigation, and hydroelectric demands have altered dynamics in river processes and greatly impacted salmon spawning and juvenile fish mortality.

Over the past two decades, researchers at Oregon State University,
led by Dr. Jerri Bartholomew, have helped shed light on factors that impact
salmon and trout populations of the Klamath. In particular, they have
revealed how the fish are affected by a deadly myxozoan parasite, Ceratonova shasta. Using molecular tools for genetically identifying unknown DNA, they established that the C. shasta life cycle involves two distinct spore morphologies that alternate between salmonid fish and polychaete worm hosts in the river. The researchers now monitor the rivers parasite spore concentrations, polychaete worm distribution, and water flow dynamics to reduce parasite effects. They know that warm, slow moving waters can stress smolts (young salmon), and if accompanied by elevated parasite concentrations, this can lead to lethal consequences for the fish hosts. Scientists and law makers now have a greater understanding of how to mitigate the mortality of juvenile salmon in the basin.

The waters of the Klamath are a limited resource, with many people who have diverse needs, and whose livelihoods rely on their well-informed, responsible management.  Decisions on water distribution commonly disadvantage certain stakeholders while benefiting others, which has lead to long standing legal battles over water rights in the watershed.  While water is needed for agricultural use, law makers periodically order hydroelectric dams along the river to increase water flow rates during migration seasons to flush the river of C. shasta spores and help to prevent the collapse of salmon fisheries in the Klamath.  Efforts are also underway to eventually remove dams along the Klamath River to revive fisheries and improve water quality.

There are stories told from the days of old
of a river flowing free
and a ruby sea
of salmon bound for a natal ground
that they knew from infancy
Calls from destiny!
As the river ran with spirit to the ocean.
Now the waters yield to concrete and rock
that lift up to the sky
and many years go by
that the salmon runs make no display
and the smolt that make it through the fray
are numbered few
while the people of the land stand in wonder.

A Klamath basin river tale,
where mysteries are illuminated
and revelations made from DNA
plunge the story to the sand
and silt where polychaetes lay hiding
bring them up and hear researchers say,
“Ooh, it’s a crazy life…”

For a parasite taking out Chinook and Coho
that were born to a river not their own from centuries ago.
With the waters high and the outflow moving slow,
there’s a plea for aquatic mercy and to hear a ruling say
Let the flood gates go!

And this is how it goes…
Ditching polychaetes, the parasites drift and hold
for a breath from the hunted and their rosy folds
a marauding crew!
With a pass through the gills, “Harpoons away!”
and a strike from nematocysts that pierce membranes
mortal games ensue
as they wiggle in to challenge prey defenses.

Now a parasite can bear no raid alone
for the smolt evolved endemic ways to hold their own
’til the ranks accrue
and the heat of the summer song’s long sustain
gives away to the burden of infection’s reign
when the siege is through
and the microbes commandeer a fulsome bounty
A salmon soon to waste away
and at the brink of expiration
the restless raiders dawn a second face
And venture to the riverbed
fickle on their host selection
to plunder sands again for polychaetes
Ooh, it’s a crazy life.

For a parasite taking out Chinook and Coho
that were born to a river not their own from centuries ago.
With the waters high and the outflow moving slow,
there’s a plea for aquatic mercy and to hear a ruling say
Let the flood gates go!