The Pelton Round Butte project on the Upper Deschutes is designed to aid fish passage to historic habitat upriver, but it’s also heating up the lower river — according to fisheries biologists, mimicking the historic temperatures our native anadromous fish evolved to handle. The results, according to the Oregonian, are temperatures 70-72 degrees at the mouth of the Deschutes.
PGE restores fish passage at Pelton Round Butte from Portland General Electric on Vimeo.
Some anglers are upset about the warmer temps, and potentially less fish in the lower river. There is an in-depth Q&A by H. Tom Davis and Bill Bakke of the Native Fish Society on how the project started and what is happening on the water.
Here is an excerpt:
If the “natural” temperatures are restored and strays, particularly hatchery strays, are discouraged from entering the Deschutes that would be a big step toward achieving natural runs of wild, native salmonids. In years past when the Columbia has been colder, like 2008, upriver fish did not stop in the Deschutes compared to years when the Deschutes is colder. In the future with the proposed releases, it may be less likely that we see upriver hatchery fish straying into the Deschutes. The increased steelhead, Chinook and reverted sockeye moving into and through the river because of reintroduction above PRB will likely make up for any losses, and probably add more fish to the lower Deschutes.
The hatchery component from upper Columbia River basin streams probably has exceeded 30,000 in some years. We may never have that increase in wild fish, but in the past hatchery strays sometimes comprised up to 65-70% of the spawning fish, affecting productivity and survival of wild fish. Reducing the stray component spawning with wild fish, especially out of basin strays, will benefit wild fish.
-MS
I certainly might be missing something, but I don’t think I’m sold on this solution. It seems like the increase in temperature on the Deschutes would make less habitat available, and end up crowding whatever fish would be there – hatchery and natives – back down into the Columbia. I guess this could be offset by the increased effectiveness of smolt capture above Pelton dam due to the change in surface flow. But then, the solution is ultimately still trucking the fish for miles up and down the river, which I thought hasn’t seemed to be much of a solution in other situations yet. Does this really have a chance of making native runs better or even keeping them at current levels?
Sounds awesome. It’s about time the D’s wild fish have a chance to dominate the run, rather than constantly being swamped by out of basin fish. This is the wild future we’ve been waiting for!
Really interesting – I agree it would be awesome to see a higher percentage of wild fish ; and yes, embracing warmer water temps, does seem counter intuitive. However thats the beauty of the D’s wild population – its ability to adapt and thrive in their unique setting. Would miss those tackle smashing B ‘s, but what a trade to see a higher percentage of wild fish looking up !
I love the way band-aids feel against the machine gun wounds.
Restoring deschutes temps to something that resembles its natural cycle sounds good but it raises a few questions for me that I haven’t been able to find answers too-
Are pre-dam (meaning-just before the dam) temperatures really what we should be shooting for? When Pelton was built was the deschutes temperature already altered by man made factors such as irrigation? Is there a way to estimate what deschutes temps were before settlement in the basin?
Just saying it could be possible that the temperature profile the deschutes is being manipulated to follow may not actually be what the deschutes was like before Lewis and Clark.
I agree with Jim, are pre-Pelton dam temperatures really the right target? What about the Columbia conditions? Those aren’t really the same conditions that Deschutes native fishes evolved under either. I think there needs to be more study on the implications of this program but in a certain sense, it beats trucking the upstream migrants, right? Overall, a difficult question.
Fished the D in the free bridge area 7/ 13 and again 8/6-7. Total of 20 hours on the water with a fly (greased line). TURNED NO FISH. Talked to 15 or so other anglers both fly and gear 8/6-7. NO ONE TURNED ANY FISH. I have been fishing this stretch for over 30 years and have never gone fishless in early August – NEVER. Warm water in my opinion has killed the lower river fishery.
What a disaster. Thanks OT, TU, ODFW, USFW, PGE. Now I can focus on better things to do in August.
PS bye, bye B-runs!
PSM (prespawn mortality) is something to be conserned about! Check out http://www.cbbulletin.com/405124.aspx and while you are at it try reading “Salmon with out rivers” There was alot of work done before the dam was constructed conserning fish migration which have come to fruition. But as is often the case nobody listened. Keep a close eye on the Rogue River; good things should begin happening now that it is free flowing.