The Umpqua River study : a joint report

The species of anadromous fish entering the Umpqua River are: chinook salmon (spring, summer, and fall runs), silver salmon, steelhead trout (summer and winter runs), cutthroat trout, shad, striped bass and sturgeon. The winter steelhead, striped bass, and shad runs appear to be maintaining themselves. The runs of the other species appear to be in various stages of depletion. Major factors which have contributed to this depletion are: overfishing by the commercial fishery and more recently the sport fishery; and barriers such as log jams, "splash" damns, mill dam and hydroelectric developments. Other factors which may be of importance are: predation; unscreened gravity water diversions; water removal by pumping for irrigation, industrial, and municipal use; and fluctuations in water levels due to meterological conditions. The total run of spring chinook salmon into the Umpqua River in 1946 was estimated to be 4,400 fish of which approximately 935 were jacks. (fish under 20 inches). The fishing mortality of shad of commercial size, in the 1946 Umpqua River run, was estimated to be 50 percent. The total catch of the various species of salmon by the commercial and sport fisheries in 1946 were as follows: Under a proper management program, an average sustained yield of several times in the 1946 catches may be expected. During 1946, anglers spent at least $292,700 in this area while fishing for salmon and trout in the Umpqua River. The capital investment was estimated to be $2,402,500. The commercial fishery products of salmon steelhead, shad, striped bass, pilchards, and crabs taken from the Umpqua River in 1946 had a wholesale valur of $652,400. The capital investment was not determined.

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