The 1997 fishwheel project on the Nass River, BC / prepared by Michael R. Link, Richard F. Alexander and Anita C. Blakley. : Fs97-4/2555E-PDF

"Four fishwheels were operated on the lower Nass River from 21 May to 4 September 1997. The fishwheels operated for a total of 7,974 h and captured 48,267 salmon. Catches of adult salmon included 28,756 sockeye; 13,167 pink; 4,004 chinook; 1,708 coho; 502 steelhead; and 130 chum. Of these, 6,513 sockeye; 2,541 chinook; 1,020 coho salmon.; and 394 steelhead were tagged. Totals of 429 chinook; 1,345 sockeye; and 367 coho salmon from the catch were successfully aged using scales. A total of 4,564 tagged fish were later recovered in upstream locations. Counts of marked and unmarked fish from the Meziadin fishway and in-river harvests were used to compute net escapement estimates for sockeye (250,456) and coho salmon (13,830). The coho estimate represented only a portion of the total coho escapement because the fishwheels did not operate through the entire coho run and recovery efforts were confined to an early run stock (Meziadin River). The net chinook escapement (18,702) was derived by a mark-recapture estimate (spawning ground surveys) minus estimated in-river harvests. The four fishwheels combined caught an estimated 18.6% of the chinook run, 10.2% of the coho run, and 10.6% of the portion of the sockeye. Including subsequent in-river harvests, an estimated 25,776 chinook and 287,242 sockeye salmon entered the Nass River in 1997. Daily tag release (at the fishwheels) and recovery data (at the Meziadin fishway) were used to reconstruct the sockeye abundance in the lower river and assess the within season variation in the portion of the sockeye run caught by the fishwheels"--Abstract, page x.

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