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We've had 3 weeks of very warm weather in June, and our temps have been above the averages for July.
This has been happening in previous years, but it this year has most everyone's attention.
My G-son works for ODFW and is doing stream/river surveys in the mid-state segments
of the Willamette River and it's tributary, the Santiam.
He says that where they would expect to see 50 - 100 salmon in the Santiam, they are now seeing only 1 or none.
The senior biologists are saying that the temp of the Willamette is too high,
so the fish are turning into the colder water of the Clackamas River,
but in that river the O2 levels are too low, and the fish are dying.
This "pre-spawning mortality" is overly affecting the females,
that usually come in later than the males.
Thus, salmon runs for the rivers in this mid-section of the State may be affected dramatically in the future.
The fish biologists are saying that removal of dams is about the only way
to keep the temps where the fish need them to be.
They have tried building massive structure to mix cold bottom-water with warmer surface water behind the dams,
but with limited releases of water, the temp starts rising again just a short way down below the dam.
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