The Osprey and a Critique

The latest issue of The Osprey is now available.  If you like to read scientific articles about steelhead and salmon conservation, mostly in the Pacific Northwest, then this is the journal for you.  I encourage you to subscribe and help keep them going.  This issue has a couple of articles that once again illustrate the peril facing anadromous fish in many PacNW river systems.  It also contains an article on the lower Deschutes River which I found problematic. 

The article gave an overview some of the history of the Pelton-Round Butte (PRB) complex of dams and the ongoing attempt to reintroduce anadromous fish into the upper Deschutes Basin above PRB, including the operation of the Selective Water Withdrawal facility (aka the “fish tower”).  It also repeated some of the common speculation about SWW impacts on the lower river which again underlines why I believe we need to be careful and refer to the best available science when voicing opinions.

The article repeats the common and unsubstantiated claim that SWW operation is damaging the lower river.  As I have extensively documented, there is no evidence of this that has held up to scientific scrutiny.  Clearly, the intended changes have occurred: the river is now warmer earlier in spring and cooler earlier in the fall in order to mimic a more natural temperature profile.  This profile should be beneficial to aquatic insects, resident fish, and migrating anadromous fish.

Annual fish counts by the Oregon Department of Fish & Wildlife have shown no decrease in the overall trout population, in particular age classes, or in condition factors (health).  If anything, trout seem to be bigger now than pre-SWW operation.  (See “Lower Deschutes fish populations & health”, which also addresses Black Spot disease as well as bass seasonally moving into the lower most Deschutes.)

A peer-reviewed, multi-year study of macroinvertebrates showed that their lifecycle timing has changed to correspond to the new temperature profile but overall populations remain excellent.  It is true that the Oregon Department of Environmental Quality initially raised questions about parts of this study but they were subsequently addressed and ODEQ now accepts the study’s conclusions.  In addition, sampling data from DEQ has not shown a meaningful increase in pH below the PRB complex.  As I wrote about here, the Deschutes is naturally a high pH river to begin with.  A new, in-depth water quality study has been completed and is currently under peer review, although it is well past the promised release date.

Omitted from The Osprey article, and most discussions of the lower Deschutes, is over fishing.  Talk to any angler who fished the river more than 20 years ago and you will hear stories of solitude.  I have only fished the Deschutes for 15 years but have heard others say it used to be infrequent to come upon many anglers.  Compare that with the combat fishing experience common today.  So, of course it now takes more skill to have a successful trip.  The businesses who popularized the river are suffering from their own success.

In short, while the angling experience has changed, the scientific evidence shows the river is healthy and the fish remain robust.  My personal experience is that I am catching bigger trout since the SWW although I have had to make adjustments in timing and tactics.  Just keep in mind, there is no bad weather, only bad clothes.  My advice is to get some good ones and fish earlier and later in the year.  The fish are still there along with less competition from other anglers.

The Osprey article does give a good overview of how poor anadromous adult returns have been.  What is missing in the article, and from SWW criticisms in general, is an acknowledgement that declines in anadromous fish populations are systemic.  Many populations in river systems from Northern California well into Canada are in dire shape and some could see extinction in the not too distant future. (See “Deschutes Steelheading: Now a Moral Issue?”)  It’s hard to draw a causal link to the SWW for precipitous declines in the entire Columbia Basin much less out of basin systems.

Clearly, anadromous populations have been declining for decades due to reasons that are well known: dams, habitat loss, over fishing by commercial and sport anglers, increased predation, pollution, etc.  An argument can be made, however, that the most pressing issue today is global heating (it’s time we moved past using the too-benign phrase “warming”, much less “climate change”).  Global heating negatively impacts freshwater habitat by causing droughts, lowering and warming rivers, and making them inhospitable to cold water fish.  This can be clearly seen in SWW fish counts: the highest outbound smolt runs have occurred following winters with high precipitation levels and the highest adults returns have been from those populations.  (See “SWW juvenile outmigration”.)  Global heating has also altered ocean chemistry, creating acidification and hypoxia (oxygen deficiency), which disrupts the food chain and starves fish.  (See “The end of local seafood?”)  For whatever reason, critics of the SWW have simply not given due credit to the systemic nature of anadromous fish declines.

This is not to say that all is well with the SWW and the overall reintroduction strategy, far from it.  As I detailed in a lengthy post (Reintroduction: Time for a Change in Strategy), it is time to acknowledge that the current reintroduction strategy is not living up to expectations even in the context of global heating.  The post went into detail on what has worked and what has not, but the bottom line is that the use of hatchery brood stock is a failing approach.  The good news is that managers are now planning to use true wild fish.  Read the post for more.

Finally, some have claimed that poor water quality in the Crooked River is the culprit behind their perceived decline in the lower Deschutes.  If so, then the Crooked should be cleaned up, not bottled up.  (See “Cooler, cleaner water?”)  Fortunately, there is an excellent opportunity to do exactly that.  This blog has extensive coverage of the ongoing Habitat Conservation Plan process that should come to conclusion this year.

Very briefly, in order for irrigation districts, farmers, and other water rights holders to continue to withdraw water from the Deschutes and Crooked Rivers (and their tributaries) they must come up with a plan that addresses incidental “take” (killing) of endangered species.  Clearly, agricultural runoff into these rivers, collecting in Lake Billy Chinook, and then released downstream into the lower Deschutes could be argued to play a role in incidental take.  I once again call on critics of the SWW to work with other conservation minded groups and focus on the unique and rare opportunity we have to use the Endangered Species Act to clean up the Crooked River, which could benefit the lower Deschutes as well.