VANCOUVER, Wash. - When Joe Hymer first saw the figure, he thought it must have been a typo.
The veteran fishery biologist for the Washington Department of Fish and Wildlife was reviewing the daily count of steelhead passing Bonneville Dam. Tuesday's figure didn't seem right: 18,671.
Because that was a full 10,000 more than the day before, Hymer figured someone must have inadvertently punched in an extra digit on the calculator. He had good reason to believe so. In the 71 years since fish counting began at Bonneville, the previous record for the daily steelhead count amounted to 14,432.
Then came Wednesday's count: 28,314.
On Thursday, the number spiked at 34,054.
The incredible steelhead counts weren't typos. At the dam, fish counters recorded as many as 1,700 silvery flashes zipping past in a single hour on Thursday a rate that equates to a new fish every couple of seconds.
"We're in uncharted waters now," Hymer said. "We haven't seen this magnitude before."
Biologists attribute this week's bulging daily counts at Bonneville largely to the searing heat wave two weeks ago. Several days of triple-digit heat warmed the river to as high as 75 degrees at Bonneville, well above the comfort level for cold-water fish.
Meanwhile, steelhead continued entering the river from the ocean.
Biologists had projected an overall steelhead run of about 350,000 this year, and Hymer said sportfishermen in the lower river have reported a successful summer so far. As the river cooled down after the heat wave ended, the theory goes, a burgeoning stockpile of steelhead were waiting to head upriver to spawn.
Juneau Empire ©2015. All Rights Reserved.