Salmon: Smallest run on Russian River in 8 years

November 21, 2007

The fall run of chinook salmon started slowly on the Russian River and, biologists said Tuesday, it hasn’t gotten any better.

So far, 950 fish have been counted passing through the Sonoma County Water Agency’s fish ladder near Forestville, which would make this year the smallest run in the eight years the fish have been monitored.

“It’s not looking terrific, and the fish appear to be later than usual,” said Sean White, a Water Agency fisheries biologist. “It should be over by now and it’s not.”

A summer conservation order was issued by the state to ensure there was sufficient water in the Russian River for chinook salmon returning in the fall to spawn. Water Agency officials warned a few weeks ago that the run seemed to be late and small, but that isn’t limited to the Russian River.

“The run is on the weak side this year,” said Andrew Van Scoyk, manager of the Rowdy Creek Hatchery on the Smith River in Del Norte County. “We are getting a decent number, but not a big run counts.”

However, White said, the Russian River has the North Coast’s most significant run of wild chinook, which are listed as endangered by the federal Endangered Species Act.Chinook, which can weigh in at 50 pounds, are native to the Russian River and found in larger streams along the coast into southern Oregon.

It always was assumed that there were a few chinook in the Russian River, but it was established as a viable population after the Water Agency put video cameras in the fish ladders at the inflatable dam at Mirabel Beach near Forestville.

That was the first time the fish were counted and since then they have been monitored from their arrival in late August until the dam is lowered, typically in November or early December.

“Chinook are the signature species of California salmon,” White said. “Chinook used to be known as the king salmon. They are really big, they will get up to almost 50 pounds . . . very large, very dramatic, very cool animal.”

In June, faced with low levels in Lake Mendocino, the state Water Resources Control Board ordered the Water Agency to reduce the amount of water it took from the Russian River between July 1 and Oct. 28.

The state order resulted in a 21.6 percent reduction as the Water Agency’s major customers, the cities and districts from Windsor to Sausalito, pushed conservation measures and used alternate water supplies.

The water was saved in Lake Mendocino for release as necessary for the chinook salmon spawning run. White said 10,000 acre-feet were saved in Lake Mendocino, and that water has been released since late October.

Until this year, the smallest run was in 2001, when 1,383 chinook were counted. The best year was 2003, when 6,103 were counted. Last year, 3,410 were counted. Biologists suspect that the cause is unfavorable ocean conditions, such as a decline in the population of krill, a tiny shrimp, at the Farallon Islands and low oxygen levels in the ocean off of Oregon.

Chinook salmon return to the ocean almost as soon as they are born, needing to find krill to feed on before moving up to herring and anchovies.

“It may make them more sensitive, they have to have smaller feed when they get out there,” Van Scoyk said.

White said that since chinook have only been monitored for eight years, it may be too early to be concerned.

“With any species there are cycles of boom and bust,” White said. “To see either of those is not necessarily indicative of an issue. It may be part of the natural cycle of things. It becomes an issue if you see it over a series of years and a series of generations.”