The Deschutes River Alliance recently made a post about the steelhead reintroduction program that, true to form, had some accurate statements which were followed by misleading and unsupported claims. It is true that somewhere around 30%, to up to 40% in some years, of reintroduced steelhead smolts are “direct release”, not released into a tributary of Lake Billy Chinook. As usual, however, the story is more complicated and nuanced than told by the DRA.

One of the major issues facing the reintroduction program is the low quality of the genetic stock of hatchery steelhead released into the Upper Deschutes Basin. These fish have been inbred for decades and are highly domesticated. The result is low survivability and a tendency to residualization (staying in rivers as trout rather than migrating to the ocean). Roughly 75% of the steelhead smolts released into the tributaries to LBC never make it to the Selective Water Withdrawal tower. The goal of naturally producing steelhead in the upper basin will only be accomplished if there are significantly higher adult returns which requires more smolts out migrating to the ocean. (See this recent post for more on this.)

Steelhead smolts are raised in the Round Butte Hatchery at the base of Round Butte Dam. After attaining sufficient size they are placed in acclimation pens in one of the tributaries of LBC. The goal of this is to imprint these tributary waters on the fish for their return. Most of these fish are released directly into the tributary but some are trucked directly to the stress relief pond near the Pelton Trap below the reregulating dam. All smolts, those trucked around the SWW or those who make it through the SWW, are held in the stress release pond for a short period prior to release into the Lower Deschutes at night when survivability is increased.

The DRA is accurate that some fish do not travel through LBC. But, their claim that travel through LBC in the spring is the reason for poor passage numbers is not supported by science. Any occurrence of “toxic algae blooms” is later in the year, if at all. Predation has been studied has not been shown to be a factor in steelhead smolt survivability. Look at the spring chinook numbers. Around 75% of the spring chinook released in the upper basin are captured at the SWW. The difference is in the nature and quality of steelhead. Spring chinook want to get to the ocean, they do not have a lifecycle that supports the possibility of staying in a river as a trout.

The DRA states that fish managers should be marking direct release steelhead smolts so that returning adults from this activity can be positively identified. This idea was considered and rejected by fish managers. It has some merit but was deemed to be too expensive, time consuming, and would add significant additional stress on the fish. With smolt out migration already so low there is little merit to adding even more stress induced mortality to these fish. Also, the genetics of these fish are identical to smolts released into a tributary.

If you’ve read this far, here’s another interesting thing to consider. Steelhead smolts resulting from natural spawning typically spend two years in their natal stream growing to smolt size. Steelhead hatcheries in the western US have robust feeding programs and grow fry to smolts in one year. They do this to maximize production and free up capacity for new fish. There is one hatchery in Washington that has the space to raise smolts over two years and these fish have shown higher survival rates. It would be great to raise smolts over two years before release, but with the current crisis in hatcheries in Oregon there is little chance of that happening at any scale.

As I have written, the best solution to steelhead reintroduction in the Upper Deschutes Basin is to remove the dams. That is not going to happen. Remember that the Pelton Round Butte project is co-owned by the Confederated Tribes of Warm Springs, a sovereign nation, that has no interest in losing the valuable revenue stream generated by hydropower generation. Short of dam removal, and given the fact that there is no credible, peer-reviewed scientific evidence that the operation of the SWW has a detrimental impact on the Lower Deschutes, I continue to support fish managers taking whatever steps they deem necessary to improve the success of the reintroduction effort regardless of results so far.