Many questions face steelhead managers

Bill Nyara

ODFW District Fish Biologist Steve Mamoyac was invited to the February 2012 Chapter meeting of the Mid-Valley Steelheaders to explain and discuss the fish management on the Santiam River system.

A great deal of information was given in the half-hour presentation, much of which dealt with the Summer Steelhead management policies and practices.

Steve explained that in 1996, the winter steelhead in much of the Willamette and Santiam systems were listed as threatened under the Endangered Species Act.

Runs of wild, native winter steelhead had dropped to just a few hundred at places such as Foster Dam. Immediately, resource agencies began to look at ways to reduce the likelihood of detrimental interaction between wild winter steelhead and the non-native, hatchery-reared summer steelhead released into the systems.

Interaction of winter and summer spawning adults was not the most pressing concern to resource managers, since spawning times were only slightly overlapping. What was a concern was the interaction of summer steelhead smolts and wild-rearing winter steelhead fingerlings and smolts. The practice at that time on the South Santiam was to truck the majority of the hatchery-reared summer steelhead smolts to several planting locations. Some smolts were also released at the hatchery.

Several things about this practice of “scatter-planting” hatchery smolts concerned managers.

Adult stray rates were known to be much higher from trucked smolts than from smolts volitionally-released directly from rearing or acclimation ponds. Straying adults tend to end up in unintended locations and are not desireable to resource managers for obvious reasons.

It was feared that the offspring from spawning summer steelhead would negatively impact the wild juveniles naturally rearing in the system. Also among those concerns was the competition between trucked smolts and winter steelhead juveniles for habitat (space) and food.

When thousands of hatchery smolts are released into an area by truck, the much smaller numbers of wild-rearing fish in the area and downstream can be displaced.

They may also be eaten by hungry hatchery smolts which may or may not migrate out soon after being trucked. It was generally felt that trucked smolts tended to migrate at a slower rate and had a greater tendancy to residualize in the stream.

When smolts leave a hatchery pond on their own volition, they have a strong migration instinct and spend much less time in the streams. Many of the smolts that don’t have the migration urge and remain in the ponds are destroyed or planted in lakes rather than in the stream where they could possibly end up as residents for a year or more, impacting wild fish.

When smolts are pumped onto a fish truck, there is no way to discern a ready-to-migrate smolt from a not-ready or never-ready- to-migrate smolt. They all get dumped into a location by the thousands, under stress which has also been proven to reduce survival rates.

So, given the fact that native winter steelhead had become listed due to years of low runs and the fact that hatchery summer steelhead were non-native (Skamania River, Wash. stock), both federal and state fisheries biologists and resource managers were faced with a challenge.

How can we continue to have a popular summer steelhead program and fishery while eliminating or at least reducing all the concerns about interaction of hatchery and wild fish, while giving the appropriate attention to the newly listed winter steelhead?

Some entities with a real or perceived stake in these new listed fish were advocating for the elimination of the hatchery summer steelhead program. Fish biologists and managers saw one very obvious practice that was believed to increase the interaction of hatchery and wild fish: scatter planting.

This was an easy way to reduce some very deep concerns while satisfying all of the governing agencies and environmental groups. It has also resulted in a sustained summer steelhead fishery for the past 14 years.

Could going back to scatter planting improve fishing? Perhaps. Some people are sure it would. Others aren’t so sure.

No one really knows and we won’t know without statistical research. On the North Santiam, such a study is being planned. Why the North Santiam? Well, because Minto Dam & Trap won’t be in operation for a couple of years. Therefore, the smolts can’t be acclimated and released there as usual.

Trucking to other sites is now required on the North Santiam, in the short term, so there’s an opportunity to try to answer the questions surrounding scatter-planting smolts. Since they have to be trucked and released, funding for a research study and creel census has been secured.

Hopefully, resource managers will learn enough to prove or disprove some of the concerns that have been driving the management of both the North and South Santiam Rivers.

Time will tell and it will take more than a year or two. Funding of the study will have to be maintained for the next few years also and during these times, that could prove to be a challenge.

Bill Nyara lives in Sweet Home and is a retired fish hatchery manager and president of the Mid-Valley NW Steelheaders. Steve Mamoyac of the Oregon Department of Fish and Wildlife contributed to this article.