Heat may overcook chinook

GOLD BEACH — Seeing the seining crew nab 15 wild fall chinook salmon from the Rogue River Wednesday at Huntley Park east of town should be a good sign for inland anglers with chinook on their minds.

These big fish in the survey net are the first real shot of prized chinook this season to head out of the Rogue bay toward the middle Rogue, where hordes of anglers await them in the most popular Grants Pass-area fishery of the year.

But with triple-digit air temperatures gripping the Rogue Valley, this best of times could become the worst of times.

Migrating chinook are headed into a cauldron of hot and likely lethal lower Rogue waters prime for a drought-triggered disease outbreak that's so far sidestepped the Rogue during one of the hottest and driest years on record.

But as hot as it will get this weekend, the image of belly-up chinook is almost inevitable.

"It'll be lava," says Pete Samarin, a fish biologist on the Rogue for the Oregon Department of Fish and Wildlife. "That river's going to be slow and it's going to be hot.

"It's going to be hard for anything to survive, chinook-wise," he says.

Rogue River temperatures at Agness are expected to eclipse 80 degrees, hot enough to trigger a columnaris outbreak, which biologists feared would take out significant chunks of the Rogue spring chinook run, and which is now drawing a bulls-eye on the upcoming fall chinook run.

The ones that have migrated past Huntley Park by now could be goners this week, but that's just the early tip of what has become a robust wild chinook run. The only hope is today's 108-degree air will cook the Rogue so hot that chinook won't venture upstream out of the bay's relatively cool, salt-infused waters.

"We'll see," Samarin says. "But it's not good."

It is good, however, if you happen to fish west of the head of tidewater.

Bay trollers are running into chinook that aren't finning upstream in any large numbers like they normally would at this time of year.

"It's not red-hot, but it's been good," says Jim Carey, who keeps tabs on the bay's fishing pulse from his Rogue Outdoor Store in Gold Beach.

Red-hot has not been a positive phrase in the history of Rogue fall chinook, whose numbers historically have been tamped down by regular columnaris outbreaks in the Agness area and the Lower Rogue Canyon due to low, hot summer flows.

But summer flow augmentation from Lost Creek Lake has changed that, cooling the Rogue most years to stave off this natural disease outbreak and creating very popular late-summer fisheries first in the bay, then the canyon and, finally, the Grants Pass-Gold Hill environs.

Drought years, however, can take their toll, like in 1992 when low water triggered a columnaris outbreak that killed off almost 70 percent of the spring chinook run and triggered an emergency fishing closure.

Shades of '92 were feared this year, but some deft water-release juggling and a very timely rainstorm helped get virtually all the springers to the upper Rogue disease-free.

The Bureau of Land Management reports no dead salmon in the canyon all of last week, so protecting that run has been a success.

But the current wave puts the all-wild fall run in peril, particularly any that get the itch to move out of the bay this weekend.

"Those chinook in the bay," Samarin says, "just need to stop."

But they won't stop forever.

Within two weeks, the chinook will start showing up in the Huntley Park survey nets. When they do, ODFW's water-management strategy calls for increasing Lost Creek Lake releases from 1,500 cubic feet per second to 1,900 cfs in an attempt to cool the water in the Agness area to palatable levels.

A dearth of natural tributary flow, however, means 1,900 cfs might be the flow at Agness. In the past, that's not been good enough to stave off disease if it's met with another round of triple-digit temps.

"I don't know if that'll be good enough," Samarin says. "My intuition tells me otherwise."

Reach reporter Mark Freeman at 541-776-4470 or mfreeman@mailtribune.com. Follow him at www.twitter.com/MTwriterFreeman.

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