Stepping out of the comfort zone on Klamath River management

Mark Johnson, Klamath Water Users Association

Klamath Project irrigators have long been stewards of the land and care deeply about the fisheries and migratory bird populations that call the Klamath Basin home.

Over the last 20 years, the management regime of “send more water” down river has become gospel. Unfortunately, no one has demonstrated that there has been any benefit to the fisheries in the lower Klamath River.

Klamath Water Users Association Fish Biologist, Mark Johnson
Mark Johnson, KWUA Fish Biologist

Meanwhile, this flow-centric focus has diminished a once-reliable stored agricultural water supply, causing an undue and unfair burden on the basin producers.

It is time to step back, re-evaluate the situation, and not be afraid to try alternative management strategies.

We have recently learned much more about Ceratanova shasta (C. shasta), the microscopic parasite that can infect salmon and cause mortality.

Last year, researchers from the U.S. Fish and Wildlife Service, Humboldt State University and Oregon State University published an article demonstrating correlations between outmigrating hatchery fish infection rates and subsequent C. shasta spore densities.

This management brief provides compelling evidence showing the impact of fish hatchery operations on C. shasta dynamics in the Klamath River.

Current Iron Gate Hatchery practices call for releasing hatchery Chinook after the natural-born juveniles have left the system to reduce competition between the wild and hatchery stocks.

On the surface, this practice seems sensible to many people. However, a deeper dive into this suggests that this practice is actually harming the entire system.

Lifecycle of polychete

Hatchery fish are often released in late spring when water temperatures, C. shasta spore concentrations, and infection rates become elevated. Infected juvenile hatchery fish pass on the parasite to the annelid (worm) host, and the worm sheds spores that infect returning adults in the fall, perpetuating the cycle.

To mitigate the impacts of C. shasta, exacerbated by hatchery releases, current river management prescribes a “flushing flow.” These flows — which can be as large as 6,000 cubic feet per second — are intended to dislodge colonies of tiny worms that serve as a host to C. shasta from the bottom of the river.

Other artificially created “dilution flows” are intended to reduce C. shasta spore concentrations when they reach levels thought to be harmful to juvenile Chinook and coho salmon.

The water from both of these types of man-made flow events is taken directly from the water supply initially developed for Klamath Project irrigators and wildlife refuges at a time when that water is needed most.

Rather than rely on “flushing” or “dilution” flows to mitigate conditions caused (ironically) by fish hatchery operations, we need to fix the underlying problem and disrupt the disease cycle at the source. Only then will we have a chance to change the disease dynamics. It is troubling to think that the prescribed flows, which come at a considerable cost of upstream stored water, are triggered by conditions caused by previous years’ hatchery releases to help hatchery juveniles currently in the system.

This type of management defies what science is telling us, and it’s an unfair burden to place on farmers and ranchers who have long depended on that water.

If this is really about the fish, the real issues need to be addressed. Hatchery management is a logical short-term solution that may help “move the needle” on the Klamath River salmon populations or disease reduction.

Time and time again, irrigators are told that “turning the knob on the Klamath Project” and sending more water downstream is easy to control and administer. Why can’t the same sort of thinking be applied to regulating hatchery practices?

Low salmon returns are not unique to the Klamath River. Anadromous fish species on other Pacific Coast rivers face the same peril. New studies suggest salmon face many stressors, particularly in the ocean, where they spend most of their lives.

However, that does not mean we should not continue to try and solve the in-river issues affecting the Klamath River Chinook and coho.

Twenty years of flow-centric management on the Klamath River has not shown a demonstrable benefit to salmon populations.

However, we can clearly point to the uncertainty it has created for farmers and ranchers trying to feed our country.

It’s about time to focus on measures that lead to recovery of the listed species in the Basin, and KWUA is dedicated towards that end. If these important species are not thriving, communities up and down the Klamath River will not thrive.

Mark Johnson is the Fish Biologist for the Klamath Water Users Association. This editorial originally ran in the February 8th, in the Capital Press.

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