Every year about this time, state and federal fish regulators set recreational commercial fishing quotas for the upcoming salmon season which begins in April and May. The weighty decision is partially based on the number of salmon in the Sacramento River.
The question is: How does anyone even know how many fish are actually in the river?
The answer lies near the small Northern California town of Red Bluff, about a 45 minute drive from Shasta Dam. Beneath a diversion dam, giant metal buckets churn and rotate in the tide, scooping up anything heading down river — pointedly, tiny Chinook salmon fry making their way to the ocean.
For 20 years, biologists from U.S. Fish and Wildlife have made daily treks to monitor these devices which are called “screw traps” — to count and measure the fish that land in the traps year round.
“This is very significant,” said Jim Smith, project leader for the Red Bluff Fish and Wildlife station. “We’ve been doing this for 20 years here — and so it gives us an idea of how the run has been doing for 20 years.”
Every day of the year, aside from Christmas and Thanksgiving, the biologists pile into a small metal boat and make their way out to the traps. The devices are cleaned of debris, and the fish are siphoned into a bucket where they’re measured and counted individually. The fish are anesthetized for the brief procedure, and returned to the river shortly after.
“These guys are out there day and night — storms,” said fish biologist Bill Poytress. “No matter, we can do whatever we can to get the best data we can.”
The data helps paint a living picture of life in the river — which helps form the base for regulators on how the fishing season will play out and how much water to release upstream on the Shasta Dam.
“It’s basically an early warning system,” Smith said. “It tells us that right now we’ve got very few fish moving downstream so there needs to be a lot of care taken for these fish.”
This year, estimates coming from Red Bluff have state and federal officials warning of a grim commercial salmon season — the toll of several years of drought and unusually warm water temperatures in the ocean. Wildlife managers said the survival rates for salmon dropped to 3 percent this year — even lower than the 5 percent estimated the year before.
“The number of fish — it is very concerning,” Smith said. “This drought has been very hard on the winter-run Chinook.”
The winter-run of federally threatened Chinook salmon pose the biggest concern. This year’s numbers paint a stark picture of the prolonged drought’s impact on the fragile fish.
“This year we’ve estimated 425,000 winter-run,” Poytress said. “In other years we’ve seen as many as 8 or 9 million.”
While commercial fishermen are likely to get a fishing season this year, unlike in 2008 when the entire season was shut down, it’ll likely be greatly limited by the small number of fish on the Sacramento River.
“The smaller the winter-run gets,” said John McManus, executive director of the Golden Gate Salmon Association, “the less time and area on the ocean the commercial fleet is allowed to fish.”
Smith recalled a time in the 80s when only a 190 winter-run adult salmon returned to the river. These days it’s around four-thousand. As the team wrapped-up its count and headed toward its next trap, he pondered the highs and lows of the fish documented by the biologists — describing himself as a glass is “half full” kind of guy.
“I think these fish will survive, they’ll come back,” Smith said. “But there’s got to be a lot of work to do.”