The effects of drought are trickling down to Klamath Basin fisheries.
A recent survey of 90 miles of the Salmon River found 55 dead adult salmon and about 300 dead juveniles, according to Sara Borok, an environmental scientist for the California Department of Fish and Wildlife.
Borok said the count was part of an annual Salmon River spring chinook dive by the U.S. Forest Service and the Salmon River Restoration Council.
“That’s higher than we’ve seen on past dives,” Borok said. “It’s worrisome that many fish have died.”
About 700 live fish were counted in cool pools fed by springs.
Flows in the estuary where the Klamath River meets the Pacific Ocean are half what they should be for successful chinook migration: As of Tuesday afternoon, flows were at 2,170 cubic feet per second (cfs), according to California Data Exchange Center reports.
“That’s low; it should be running at about 4,000 cfs,” Borok said.
Also as of Tuesday, at 2:30 p.m., the estuary temperature was 76.2 degrees Fahrenheit, according to the center. Borok said warm water holds less oxygen and encourages parasites; chinook seek out cold water refuge when water temperatures hit 72 degrees.
Borok said officials are hoping temperatures or some precipitation will drop soon.
“These fish usually don’t start spawning until early September. Peak spawning is in early October, so we have that much time until the fish complete their lifecycle,” said Tom Hotaling, fisheries coordinator for the Salmon River Restoration Council.
Borok said resource managers have been monitoring conditions since May.
“All eyes are on the river and have been for a while now,” Borok said.
Borok said adult spring chinook are holding in cold water refuge areas along the Salmon River, but fall Chinook beginning their inland spawning migration in August could soon add to the congestion.
Stakeholder organizations and agencies are meeting to troubleshoot the water shortage and the danger it poses to fish, Borok said.
Water is being released into the Klamath River in accordance with flows outlined in a 10-year joint biological opinion created by the U.S. Fish and Wildlife Service and the National Marine Fisheries Service in 2013. The collaborative opinion provides management guidelines for protecting species on both sides of the Oregon-California border: Management operations are intended to meet the needs of coho salmon in Klamath River, while balancing the needs of listed suckers in Upper Klamath Lake.
Brian Person, area manager of the Bureau of Reclamation (BOR) Northern California Area Office, said the Salmon River is not within BOR jurisdiction, but even if it was, there is no way to get more water into the river. The Salmon River is a tributary of the Klamath River and does not have any water control features or dams.
The Associated Press reported posters have been distributed asking people to report when they see an unusually high number of dead fish — more than 55 in a mile of river.
In 2002, a combination of remnant drought effects and continued agricultural water deliveries caused low, warm water in the Klamath River, resulting in a massive fish kill. More than one-third of the 181,000 chinook fall run died from gill rot disease that spread as the fish crowded into low and warm pools while waiting for higher water to move upstream to spawn.
Before the historic die-off, the annual Salmon River dive revealed only 22 dead adult chinook — less than half of the adult fish found this year.
Hotaling said the lowest run on record occurred in 2005, three years after the die-off: only 90 fish returned to the Salmon River.
“It certainly is a concern if you get too many low runs in a row,” he said. “You lower the possibility of rebounding.”
The Salmon River is a tributary of the Klamath River, and home to one of the last remnants of spring chinook salmon in the Klamath Basin, which return from the ocean in spring and stay in the river until October, when they spawn and die.
Borok said the fall chinook run is expected to be 92,000, not 60,000, which has been reported in other stories.