The 1995 fishwheel project on the Nass River, BC / prepared by M.R. Link and A.C. Gurak. : Fs97-4/2422E-PDF

"Four fishwheels were operated on the lower Nass River from 8 June to 4 September 1995. The fishwheels operated for a total 6,762 hand captured 34,642 salmon. Exclusive of jacks, the catch comprised 21,090 sockeye, 8,881 pink, 1,837 coho, 920 chinook, 224 chum, and 111 steelhead. Of these, 9,031 sockeye, 842 coho, and 719 chinook salmon were tagged. A total of 6,445 tagged fish were later recovered in fisheries and on tributaries of the Nass River. From 28 July to 20 August, a total of 2,044 sockeye were selectively harvested from 2 of the fishwheels. We used counts of marked and unmarked fish from the Meziadin fishway and inriver harvests to compute mark-recapture escapement estimates for sockeye (264,685) and coho salmon (25,253). The coho estimate represents 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 (7,844) was estimated using carcass and tag recoveries from several spawning grounds in the watershed. The 4 fishwheels caught an estimated 7.5% of the sockeye run, 9.2% of the chinook run and 7.5% of the portion of the coho run that had similar run timing as the Meziadin River stock. We used daily tag release (at the fishwheels) and recovery data (at the Meziadin fishway) 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. As in previous years, fishwheel efficiency varied significantly within the season. The peaks in fishwheel efficiency on sockeye in 1995 appeared to be related to the absolute level of the Nass River"--Abstract, page x.

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