Carving a path through the debate over upper Willamette steelhead

 

Carving a path through the debate over upper Willamette steelhead

 

There are no easy decisions in the world of steelhead conservation and management, but some issues are more difficult than others, such as hatcheries.

 

Although the science on hatcheries is solid and critical to guiding management of wild steelhead, there is a role for hatcheries, as long as we strike a balance by also ensuring there are streams for wild steelhead that are free from hatchery effects.

 

Our past polling of anglers of all creeds indicates they prefer a range of angling opportunities, ranging from catch-and-release of wild steelhead to harvest opportunities for hatchery fish. There is a way to implement such an approach.

 

Anglers are looking for a portfolio of opportunity that reflects their diversity.  This can be provided in each region by identifying those rivers with the strongest populations of wild steelhead and the best remaining habitat and using those places as primary populations that are free from releases of hatchery steelhead and their myriad of negative effects on wild fish.  These streams are the crown jewels, if you will.

 

Alternatively, we support well-managed hatcheries in those watersheds where populations are so depleted and/or where habitat conditions are so altered that wild steelhead are unlikely to recover in a human lifetime.  We call it a “portfolio approach”.

 

The portfolio approach can provide the diverse types of fishing opportunity that we are after, while also ensuring that wild steelhead populations with the best chances of thriving will have every opportunity to do so.

 

In this context, each of us anglers give a little to gain more stability in fish and fishing.

 

A few weeks back we published a blog post that supported the continued production and release of hatchery summer steelhead from the ODFW below Dexter dam. These hatchery summer steelhead are released in the upper Willamette near the cities of Eugene and Springfield, Oregon. We also expressed support for the summer steelhead hatchery program in the McKenzie River (also located in the upper Willamette basin).

 

This position has generated some controversy.  Some groups want cessation of hatchery summer steelhead in the Upper Willamette Distinct Population Segment (DPS), where wild winter steelhead are listed as Threatened under the Endangered Species Act (ESA).  Others want to maintain, or even increase, the number of hatchery releases.

 

We understand both sides. On one hand, the hatchery summer runs are not from the Upper Willamette DPS, they are a hybrid from the Washougal and Klickitat Rivers in Washington.  On the flip side, the fishery is critical to local anglers and businesses and it attracts enough people to help alleviate pressure on nearby wild summer run fisheries like the North Umpqua, Rogue, Deschutes, and Siletz, which can use all the help they can get.

 

One reason we support hatchery releases at those locations is because wild summer steelhead never existed above Willamette Falls historically, but winter runs did and continue to do so.  The upper-most distribution of wild winter steelhead ends at the Calapooia River.

 

Consequently, summer steelhead adults from releases at Dexter, the Town Run, and the McKenzie River will be returning to streams that never supported wild steelhead.  We understand some of those adults will stray into the North and South Santiam, and perhaps even the Molalla, but those strays are limited overall and the fishery for hatchery summer runs provides opportunity for anglers that would not otherwise exist.

 

The majority of wild winter run steelhead in the upper Willamette return to the Molalla and North and South Santiam Rivers.  The Molalla does not receive plants of hatchery steelhead, and the ODFW say the population has been responding well.  The North and South Santiam Rivers both receive plants of hatchery summer runs.  Data on the non-native hatchery summer runs is concerning in both Santiams.

 

Let’s take a look at what we know about the interactions between hatchery summers and wild winters in that basin.  First, a genetic study published by Johnson et al. (2013) found that 10% of the unmarked steelhead smolts they sampled at Willamette Falls from 2009-2011 were summer steelhead and an additional 10% of the samples were wild winter steelhead x hatchery summer run hybrids.  Specifically, hatchery summer steelhead x wild winter steelhead represented 11.1% and 14.8% of the samples.

 

Second, a follow up study on genetics of steelhead in the upper Willamette by Weigel et al. (2019) sampled returning adults at the falls and found 26.4% of the fish were hatchery summer run x wild winter run hybrids.  Accordingly, both genetic studies suggest fairly high levels of hatchery introgression in the North and South Santiam wild winter steelhead.

 

Third, a recent radio-telemetry study by Erdman et al. (2018) tracked the movement of recycled hatchery summer steelhead and used that data to estimate how many hatchery summers were not returning to the hatchery. Their estimates indicate the number of recycled hatchery summer steelhead remaining in the South Santiam exceeded the spawning population size of wild winter runs.

 

The greatest difference occurred in 2012 when the estimated population of hatchery summer steelhead remaining in the South Santiam was six times higher (4647 hatchery summers vs. 811 wild winter runs) than the estimated escapement of wild winter run steelhead.

 

Lastly, research on hatchery summer steelhead smolts in the South Santiam by Harnish et al. (2014) found that only 25% of the smolts emigrated to Willamette Falls, while the last known location of most fish (60%) was in the South Santiam River, and some of those were still alive over three months after release.

 

Unfortunately, the highest densities of residual hatchery steelhead were within 10 km of the South Santiam Hatchery, which is considered to also be some of the highest quality rearing habitat for wild juvenile steelhead. Hence, the authors suggested it is possible that residual hatchery smolts are displacing wild steelhead from the highest quality habitat into suboptimal habitats.

 

These studies don’t paint a pretty picture for wild steelhead in the North and South Santiam River.  The extent of introgression with the hatchery summer steelhead is particularly concerning, as is the dramatic imbalance between wild and hatchery spawners in the South Santiam. Given this, hatchery management needs to change in both Santiam Rivers.

 

We propose a portfolio approach to the upper Willamette.  Hatchery summer runs would continue to be released in the Willamette downstream of Dexter Dam, through the “Town Run” reach in Eugene/Springfield, and in the McKenzie River.

 

However, we would eliminate hatchery summer steelhead releases in the North Santiam to reduce hatchery introgression with wild winter steelhead.  We believe its habitat and population of wild steelhead has the best chance moving forward.

 

Although the hatchery effects appear extensive in the South Santiam, we would maintain hatchery summer run releases in the South Santiam, but with some conditions.

 

First, eliminate recycling of hatchery summer steelhead because it contributes to very high levels of hatchery spawners in the river. Second, increase the bag limit from three to four hatchery summer steelhead per day to increase harvest levels and reduce hatchery fish spawning in nature.  Third, we would like to see improved monitoring of steelhead in the Willamette Basin and subsequent modeling to estimate the extent of hatchery effects.

 

This approach provides continued fishing opportunity for hatchery summer steelhead. It also adopts recommendations to help improve the status of wild populations, as provided by the authors of the studies we reviewed.

 

For example, Weigel et al. (2019) suggests it is important to protect the remaining intact populations, either by designating genetic preserves where hatchery fish are not released or by improving reproductive isolation between the two stocks.

 

Similarly, Johnson et al. (2013) suggested it was important to improve reproductive isolation between wild and hatchery steelhead and continue monitoring to provide further clarity on hatchery effects.

 

Our approach will accomplish all of those. By eliminating hatchery summer runs from the North Santiam we provide a genetic refuge for wild steelhead, and establish the type of conditions necessary for a large-scale experiment where managers could compare how the North and South Santiams respond to changes in hatchery plants.

 

That type of experiment would provide valuable information that could be used to improve management of wild and hatchery steelhead moving forward.

 

Back to the beginning — there are no easy solutions here. But the portfolio approach to managing for steelhead in the Willamette River watershed represents an opportunity for all of us – wild fish zealots to hatchery fish devotees – to come together and learn how these different hatchery strategies work relative to one another in terms of conservation and fishing opportunity.

 

TU and Wild Steelheaders United will continue to push hard for rivers with high wild steelhead potential, such the North Santiam River, to be managed exclusively for wild fish because the evidence shows that it is the best bet both for reliable, sustainable fishing opportunity and conservation of wild steelhead.

 

The challenge of managing hatchery and wild steelhead is a microcosm of a larger issue across the range of wild steelhead in the Lower-48. Anglers want sustainable fishing opportunity. We get that. We are anglers ourselves. At the same time we want to recover wild steelhead, a requirement under federal law. The portfolio framework described here is the best approach for meeting these dual objectives.

 

References

 

Johnson, M. A., T. A. Friesen, D. J. Teel, and D. M. Van Doornik. 2013. Genetic stock identification and relative natural production of Willamette River steelhead. ODFW and NOAA Fisheries for U.S. Army Corps of Engineers Portland District, Portland, Oregon, USA.

https://odfw.forestry.oregonstate.edu/willamettesalmonidrme/sites/default/files/hatchery-research/odfw_willamette_steelhead_genetics_synthesis.pdf

 

Erdman, C. S., Caudill, C. C., Naughton, G. P., and M.A. Jepson. 2018. Release of hatchery adult Steelhead for angler opportunity increases potential for interactions with endemic Steelhead. Ecosphere 10: e0244

https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.2448

 

 

Harnish, R.A., Green, E.D., Vernon, C.R., and G.A. Mcmichael. 2014. Ecological interactions between hatchery summer steelhead and wild Oncorhynchus mykiss in the Willamette River basin, 2014. Pacific Northwest National Laboratory (PNNL), Richland, WA (US).

https://www.osti.gov/biblio/1167313

 

 

Weigel, D.E., Adams, J.R., Jepson, M.A., Waits, L.P., and C.C. Caudill. 2019.  Introgressive hybridization between native and non‐local steelhead (Oncorhynchus mykiss) of hatchery origin. Aquatic Conservation: Marine and freshwater ecosystems 29: 292– 302. https://doi.org/10.1002/aqc.3028