Published June 24, 2004

By DYLAN DARLING

Scientists scoured 87 miles of the Klamath River last week for salmon fingerlings killed by a microscopic parasite.

What they found was both unsettling, and uncertain.

"Anyone on the river will tell you that there are fish dying every day," said Ron Reed, biologist for the Karuk Indian Tribe.

Ceratomyxa shasta, or C shasta, has killed high percentages of salmon fingerlings found in traps along the river since early May, but it's hard to figure out how those numbers relate to the amount of fish that survived in the river, and to what is normal, officials said.

Presence of the parasite raises concern for the 5 million salmon fingerlings released from the Iron Gate fish hatchery from late may to early June.

Reports show 269 dead salmon fingerlings have been recovered from the Klamath River. But biologists say there's no way to extrapolate what percentage of the fish in the entire river system may have succumbed to the parasite.

"Because this is the first year of this kind of survey it is hard to say if it is worse this year or different," said John Engbring, director of the U.S. Fish and Wildlife Service's California and Nevada Operations office in Sacramento.

Divers observed that C shasta has made its way downriver, affecting clumps of fingerlings in the lower part of the river's middle reach.

The survey data were released at a meeting of the Klamath Fisheries Task Force, a group of federal and state officials, tribes and stakeholders that has meet three times a year since 1986. The meeting, being held in Klamath Falls at the Shilo Inn, started Wednesday and ends today.

The C shasta parasite is common to main stem of the Klamath River, from the Pacific Ocean to the Williamson River. But there is no data on how many salmon it affects per year.

"I don't think any of us know how this would compare to other years," Engbring said. "This is really a baseline."

The parasite spends part of its life inside tiny, 3-millimeter long worms that float in the river's water, and the other part inside salmonid fish, which include, salmon, steelhead and trout.

While inside the fish, the parasites eat away at the intestines, multiplying and causing a lethal infection. Fish with C shasta usually die.

"Once they get it, they are the living dead," Manji said.

Although the percentage of fish being found dead from C shasta in the four traps along the stretch of river is high - up to 95 percent - the number of fish caught in the traps is relatively low, said Neil Manji, fisheries biologist for California Department of Fish and Game.

"You don't even know how many fish have gone by," he said.

So trying to figure out how many fish are affected becomes a percentage game, he said.

To try to get a better idea of how the parasite is affecting fish in the river, scientists blitzed the river last Thursday and Friday.

Fourteen scientists from federal and state agencies, as well as American Indian tribes and private groups, fanned out from Happy Camp. Using kayaks, jet boats and rafts, as well as snorkels and underwater video cameras, they looked for signs of a fish dieoff on the stretch of river between Klamath and Big Bar.

Along with C shasta, another parasite called parvicapsula, which attacks a fish's kidneys, has been found in Klamath River salmon.

Manji said the parasite is similar to C shasta, and often fish get affected by both, so it is hard to tell which of the parasites caused a fish's death.

The parasites have been infecting this year's hatch, which emerged from spawning beds, in and out of the Iron Gate hatchery, in December and January, which are now about the size of a human's pinky finger.

People along the river are not the only ones concerned about the parasites.

Dan Keppen, executive director of the Klamath Water Users Association, said Klamath Reclamation Project irrigators are worried that blame for the spread of the parasite could be put on the Project if "catastrophe theorists go wild."

He said more research need to be done about the parasites.

"We need to know how this relates to past years," Keppen said.