One of the issues that stimulated the development of this workshop is the straying of Umatilla River Hatchery fall-run chinook salmon into the Snake River. I thought that it would be worthwhile to provide a background on the history of the Umatilla fisheries restoration program with specific relevance to the straying issue. I believe this restoration program serves as a good example of how conflicts can arise when we pursue management activities in one subbasin that result in unexpected outcomes that conflict with achievement of objectives in other subbasins--a case in which we have conflicting cultural and societal demands.

The Umatilla River is located in the northeastern corner of the State of Oregon and enters the Columbia River at rkm 465, 58 km downstream from the confluence of the Snake and Columbia Rivers. Historically, the Umatilla Basin supported populations of summer-run steelhead, fall- and spring-run chinook salmon, coho salmon (O. kisutsch), and possibly chum salmon (O. keta). Endemic stocks of fall- and spring-run chinook and coho salmon are extinct and summer-run steelhead are depressed.

As a result of these activities, an aggressive restoration and supplementation program for fall- and spring-run chinook salmon, coho salmon, and summer-run steelhead was initiated. To guide this effort, a comprehensive plan for rehabilitation of anadromous fish in the Umatilla Basin was developed. An extensive planning and review process was completed under the Northwest Power Planning Council's Fish and Wildlife Program prior to initiation of the rehabilitation efforts. This process involved numerous agencies, tribes, and fisheries experts from the Pacific Northwest to establish management and research objectives and restoration strategies. The plan identified specific management objectives to restore the natural production of fall-run chinook salmon and to meet tribal treaty obligations. Similar objectives were established for summer-run steelhead. In both programs, efforts were made to limit the influence of hatchery stocks on resident and endemic populations. The reintroduction of anadromous salmon into the Umatilla Basin, as well as the supplementation of summer-run steelhead, was implemented only after a long, well thought-out planning process.

In addition, an array of other objectives in the areas of habitat restoration, flow enhancement, and passage improvement were developed to improve environmental conditions in the basin. Juvenile and adult passage improvements have been made at several diversion dams and ladders. Flow enhancement projects to pump water out of the Columbia River to replace water diverted for irrigation are nearing completion, and trap and haul programs are under way to move adults and smolts up and down the river at times when river conditions are not suitable for passage.

The largest investment in the rehabilitation effort has been in the hatchery program, which is considered the cornerstone of the program. Large-scale production goals were established to meet the adult objectives that were developed in the rehabilitation plan. The Umatilla Hatchery was constructed to meet the hatchery production needs. This facility is located on the shore of the Columbia River and is supplied with well water. The plan identified the need for production and release of 7 million juvenile fall-run chinook salmon annually; however, a full program has not been achieved, and only about 3 million fall-run chinook salmon have been released annually. One surprise outcome of the fall-run chinook salmon hatchery program was the extensive degree of straying that occurred among adult fall-run chinook salmon that should have returned to the Umatilla River but returned instead to the Snake River. Table 1 shows the total escapement to Lower Granite Dam, and the composition of escapement including the number of wild fish, numbers of Lyons Ferry Hatchery¹ fish, and number of Umatilla strays. The actual number of Umatilla fall-run chinook salmon straying into the Snake River was greater than that depicted in Table 1, because a substantial number entered the Snake River but did not reach Lower Granite Dam. Several factors likely contributed to and promoted straying of Umatilla River fall-run chinook salmon. Early in the program, juveniles were released in the lower part of the river near the confluence with the Columbia River and were not acclimated prior to release. Low flows and warm water temperatures occurred in the fall at the time adults should have entered the Umatilla River and presumably discouraged adults from migrating upstream.

We have made a substantial number of improvements in an attempt to reduce the rates of straying: juveniles are released in the upper part of the river and are acclimated prior to release; all fish are marked with magnetized wire and with a unique fin clip so the fish can be trapped and removed at dams on the Snake River; and river flows have been increased in fall to provide improved water quality, greater attraction, and better migration conditions in the river. It is our belief that these changes will reduce the straying to an acceptable level. However, only future information will allow us to determine if we have reduced levels of straying to acceptable levels.

Table 1. Origin of fall-run chinook salmon returning to Lower Granite Dam from 1990-93. Lyons Ferry = Lyons Ferry Hatchery fish; Umatilla = hatchery fish released in the Umatilla River.

Question: Bob Hayman (Skagit System Cooperative): Is there a reason why you would assume that natural Umatilla chinook salmon did not also stray into the Snake River before they went extinct?

Answer: Richard Carmichael: We have not assumed anything about historical levels of straying into the Snake River from the natural populations in the Umatilla River Basin. We do know that the Snake River populations are severely depressed and that there is probably an imbalance in these numbers relative to what may have been there historically when Snake River populations were large. Historically, Snake River production probably dwarfed Umatilla River production, and straying from the Umatilla River Basin into the Snake River was not important.



Footnote

1. This hatchery was established to propagate Snake River fall-run chinook salmon.

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