Spring chinook numbers down in Yakima River

The Yakima River spring chinook season is a fishery annually awaited by anglers with the same kind of fervor as a child awaits Christmas morning.

This year, though, there’s been a Grinch in the gift pile.

Maybe it’s “the Blob,” that mass of unusually warm water that showed up in late 2013 and all but wiped out nutrient bases for the fish trying to survive within it. Perhaps it’s climate change, creating river conditions that favor not the anadramous species but, rather, the voracious warm-water species that prey on the outgoing smolts.

Whatever the reason, the projected run of 4,610 adult springers to the Yakima River is roughly 55 percent of the 10-year average and includes just 1,510 hatch-origin fish — less than the 1,579 fish that were actually harvested during the 2011 non-tribal sport fishery on the Yakima.

The result: Washington Department of Fish and Wildlife managers are taking a cautious approach to this year’s Yakima River springer fishery, with a daily limit of two hatchery chinook — only one of which, though, not the fishery’s traditional two — can be an adult.

And, in another first, they’ve set the dates for the season on the lower river below Prosser — April 29 through June 15 — without announcing dates for the more-productive Union Gap-to-Roza stretch.

“We’ve always set the lower and upper (river fisheries) at one time,” said John Easterbrooks, the WDFW’s regional fish program manager for the department’s Yakima-headquartered Region 3. “They may be staggered time-wise, because we tend to open the lower one a week or two earlier.

“But this year we de-coupled it because of the forecast. I’m intentionally delaying (announcing the upper-river fishery), because as it stands now there’s a good chance that one won’t happen at all.”

Easterbrooks doesn’t believe that will be the case; he still expects the numbers to warrant an upper-river fishery in the upper river below Roza Dam, where the vast majority of the spring chinook caught in any year are harvested. But even if the fish are there, he’s not as sure about whether river conditions will make it worthwhile for anglers to try to catch them.

“The river conditions are going to make it dicey,” he said. “Last year it was low (water levels) and clear because we didn’t have any snow, so that made fishing conditions good day-in and day-out.

“This year we’re going to have snowmelt. This week (temperatures are) going to be in the 80s, and we’ll probably get our first 95- or 100-degree days in May, and when that happens the whole river will be chocolate — it will blow out and be unfishable.”

Still, WDFW fish biologist Paul Hoffarth will be doing creel census during the lower-river season, Easterbrooks said, “and we’ll see if the river is in any shape and people are catching any fish. The key is, we get a complete count at Prosser, so we’ll have a known quantity.

“I would love to see (the total Yakima run) come in at 6,000 fish instead of 4,610.”

The latter number, though, is the forecast put together by Bill Bosch, data manager for the Yakima Klickitat Fisheries Project, and Bosch’s projections have been pretty close to spot on for each of the last four years — over the actual return numbers by less than 9 percent each year, with two years missing by only roughly 3 percent.

And Bosch isn’t optimistic.

“We’ve had a lot of late runs in recent years, so the fish haven’t shown up at Bonneville yet, but I’m certainly nervous that, sooner or later, what’s been happening in the ocean is going to catch up with us,” Bosch said. “The 4-year-old fish that will be coming back this year spent much of their life out there in that Pacific warm blob.

“I think the ocean is different than what it used to be, in terms of being predictable, and we also know with the warming ocean there’s been effects on the pH balance; it’s become more acidic out there, and how does that impact the food chain? Do these fish have the same amount of food in the same places, or are they having to further further for food and use more of their energy reserves to do so? Does it make them more susceptible to predation?

“All of the things happening can impact (the fish returns).”

Bosch said last year’s return of jacks to Bonneville indicated “relatively poor survival” in the ocean of the generation that would make up the bulk of the 2016 run.

But, of course, it’s still too early to tell. Fewer than 5,000 spring chinook have made it through the fish ladders at Bonneville, out of a run of nearly 300,000 expected to the mouth of the Columbia and an expected 188,800 bound for destinations further upriver.

This story was originally published April 20, 2016 at 1:52 PM with the headline "Spring chinook numbers down in Yakima River."