Fewer than half the salmon expected to enter the Klamath River in California this year have moved inland, but environmental scientist Sara Borok said water conditions are favorable and it’s still too early to gauge the final count.
Only about 106,000 fish have made it into the Klamath and its tributaries, Borok, a scientist for the California Department of Fish and Wildlife, said.
“It’s not as many as last year, but it’s not poor,” she said. “The water is cool and clear, but low. That’s not uncommon for this time of year.”
According to Borok, 323,000 salmon were recorded in 2012, making it the largest run since recording began in 1978. Scientists predict the 2013 run could be as large as 272,000; however, Borok said a number of factors influence Klamath salmon counts.
Winter storms this year filled the mouth of the Klamath River with silt and kept fish from entering the river, she said. The added sediment also created sandbars along the mouth, which allowed more sport fishing and increased ocean harvests.
“Around Labor Day weekend there were probably about 1,000 people fishing down there,” Borok said.
It wasn’t until a late September storm blew out the mouth of the river that salmon were able to freely migrate inland.
According to Morgan Knechtle, a CDFW environmental scientist, Chinook began spawning two weeks ago in Siskiyou County. He also pointed out that fish don’t often enter lower Klamath tributaries and some miscellaneous streams until later in the season.
“Blue Creek fish might not even be in the river yet,” Knechtle said.
In 2012, lower Klamath and miscellaneous tributary fish accounted for 4 percent of the total count.
In June, threats associated with high water temperature led the Klamath Fish Health Assessment Team to classify the Klamath River readiness level “yellow,” which required heightened fish and water quality awareness among environmental monitors and biologists.
“We were certainly concerned in September about a fish die off, but the climatic conditions turned favorable,” Knechtle said.
One factor that helped stabilize river health was an order by Bureau of Reclamation to release water from the Trinity River into the Klamath. The release lasted from mid-August until late-September, Borok said. Another boost came from a scheduled water release for the Hoopa Valley Tribe’s boat dance, also held in August.
“That water was critical, and it set the stage to cool the water down,” she said.
In mid-October, the river was downgraded to green after the threat of a potential fish kill disappeared altogether.
“Flows increased in many of the tributaries due to rain and the end of the irrigation seasons, and water temperatures decreased with the cooling air temperatures,” Katharine Carter, an environmental scientist with the North Coast Region California Regional Water Quality Control Board, said in an email.
Effects from environmental events in previous years will also influence how many fish will enter the river this year.
According to Knechtle, the high volume of 2012 fish can be traced back to favorable river and oceanic conditions in 2010, when ideal water temperatures and abundant food sources promoted successful fresh- and salt-water migration.
However, not all Klamath tributaries are reaping these rewards. That same year, heavy rain scoured out salmon nests, called redds, in the Salmon River. This led to fewer fish making their way to the ocean and back into their natal streams the following year.
“We’re not expecting to see a large return on 2-year-old fish in the Salmon River,” Borok said.
The average Klamath River salmon run is 122,000. Borok said even if the 2013 estimate is not met, it’s likely the run will meet the average.
“The take home message is that we’re not done counting,” Borok said.