Joint Transboundary Technical Committee - Transboundary River Salmon Production, Harvest, and Escapement Estimates, 1994. TCTR (96)-2. May, 1996.

Estimates of catches and escapements of Pacific salmon returning to the transboundary Stikine, Taku and Alsek rivers for 1994 are presented and compared with historical patterns. Relevant information pertaining to the management of appropriate U.S. and Canadian fisheries is presented and the use of in-season management models is discussed.

The 1994 Stikine sockeye run is estimated at 208,000 fish, of which an estimated 133,900 fish were harvested in various fisheries, 3,400 were used for brood stock, and 70,800 escaped to spawn. The catch was the second highest recorded since 1982 when stock identification techniques were first used for marine catches. The total run was the fourth highest, with the escapement slightly less than the 1984-1993 average of 77,000 sockeye. The estimated U.S. marine commercial catch of Stikine sockeye salmon was 80,500 fish; the Canadian in-river commercial, aboriginal, terminal, and test fishery catches were 40,900, 4,200, 6,900, and 1,400 fish, respectively. Enhanced sockeye salmon from outplants in Tahltan Lake contributed an estimated 18,300 and 6,400 fish to the U.S. and Canada catch, respectively. The pre-season forecast of the run ranged from 312,000 (Canada) to 346,000 (U.S.) sockeye, quite a bit greater than the post-season estimate of 208,000 sockeye. In 1994 the Stikine Management Model correctly predicted a larger than average run for both the Tahltan and the total Stikine sockeye stocks. Weekly in-season model forecasts ranged from 141,100 to 382,000 sockeye salmon; the final in-season prediction was 249,300 to 356,200 fish, Canadian and U.S. estimates, respectively. Canadian commercial and aboriginal fisheries harvested 29% of the total allowable catch, which was below their 50% allowance. The sockeye escapement to Tahltan Lake was 46,400 fish, 47% above the 1984-1993 average and above the spawning escapement goal of 24,000 fish. A brood-stock take and terminal fishery removed 3,400 and 6,900 sockeye salmon, respectively, from the escapement to the lake, leaving a spawning escapement of 36,100 fish. The estimated spawning escapement of 34,600 non-Tahltan Stikine sockeye salmon was within the escapement goal range (20,000-40,000 fish) for this stock group.

The chinook catch in Canadian commercial and aboriginal fisheries in the Stikine River was 2,100 fish., 93% of the 1984-1993 average; in 1994 approximately 58% was harvested in commercial fisheries and 42% in the aboriginal fishery. An additional 370 chinook salmon were taken in the Canadian in-river test fishery. The U.S. marine catch of chinook salmon in the District 106 and 108 mixed stock gillnet fisheries was 2,800 fish, approximately 39% above the 1984-1993 average catch. The chinook spawning escapement of 6,400 large adults through the Little Tahltan River weir in 1994 was 15% above the 1985-1993 average and 20% above the joint U.S./Canada escapement goal of 5,300 fish. Surveys of two other Stikine tributaries showed below average escapements.

The U.S. marine harvest of Stikine River coho salmon is unknown since their is no stock identification program for this species; however, total mixed-stock coho catches of 267,800 and 44,900 fish in Districts 106 and 108, respectively, represented record catches and were more than 97% and 459%, respectively, above the 1984-1993 averages. Alaskan hatchery fish comprised approximately 13% (41,900 fish) of the coho harvest from the two districts. The Canadian in-river coho catch of 3,400 fish was less than the expired treaty entitlement of 4,000 fish. The coho escapement above border was estimated at 46,000 fish, within the escapement goal range of 30,000 to 50,000 coho. Coho survey counts were above average.

The 1994 Taku River sockeye run estimate is 227,300 fish and included an estimated catch of 127,200 fish and an above-border escapement of 100,100 fish. The catch was 23% above the 1984-1993 average. The total run size was 3% above the 1984-1993 average of 203,300 fish. The escapement was about equal to the 1984-1993 average of 99,800 sockeye, however, it exceeded the upper level of the escapement goal range of 71,000 to 80,000 fish. An estimated 97,000 Taku sockeye were taken in the District 111 commercial fishery and 1,100 sockeye in the U.S. in-river personal use fisheries. Canadian in-river commercial and aboriginal fishery catches were 28,800, and 240 sockeye, respectively. The expired harvest agreement for wild Taku River sockeye salmon was 18% of the total allowable catch to Canada and 82% to the U.S. Since the escapement goal is expressed as a range, the resulting TAC is also repressed as a range. In 1994, Canada took an estimated 19% to 20% and the U.S. took 63% to 67% of the total allowable catch.

The catch of large chinook in the Canadian commercial fishery in Taku River was 2,100 fish, 2.6 times the 1984-1993 average of 800 fish; in addition, 240 jack chinook were caught compared to an average of 160 fish. The chinook catch in the District 111 mixed stock gillnet fishery was 5,000 fish, almost twice the 1984-1993 average. The majority (68%) of chinook caught were mature spawners; 58% of the catch was of Alaska hatchery origin. Above average escapements were observed in all six of the Taku River chinook index tributaries. The combined aerial survey count of the index tributaries was 9,900 fish, which is 11% above the 1984-1993 average of 8,900 fish, but 25% below the index escapement goal.

The Taku coho run was strong in 1994. The U.S. harvest of 188,500 coho salmon in the District 111 mixed stock fishery was the highest on record and exceeded the previous 10-year average by 175%. Alaskan hatcheries contributed an estimated 14% of the District 111 harvest, or approximately 27,100 fish. The Canadian in-river commercial and food fishery catch was 14,700 coho salmon, well over the expired annex limit of 3,000 fish. The in-river run size was estimated at 111,000 coho. After upriver Canadian catches are subtracted from the in-river run, the resulting above-border escapement is estimated at 96,300 coho salmon, which far exceeds the interim escapement goal range of 27,500 to 35,000 fish.

The catch of pink salmon in District 111 was 401,500 fish, the largest catch in history and 2.5 times the 1984-1993 even-year-average catch. The Canadian commercial in-river harvest of pink salmon was 168 fish. The escapement of pink salmon to the Taku River was very good as evidenced by the fish wheel catch of 27,100 pink salmon, a record even-year count, and well above the 1984-1992 even-year-average of 10,900 fish.

The catch of chum salmon in the District 111 fishery was 214,200 fish, composed of 198,000 summer run fish (prior to mid-August) and 16,200 fall run fish. The catch of summer chum salmon, primarily of Alaskan hatchery stocks, was 27% above the previous record catch of 1993. The catch of fall chum salmon, composed of wild Taku River and Port Snettisham stocks, was 51% below the 1984-1993 average. The Canadian in-river catch of 18 chum salmon was below average. Escapement appeared to be poor; the fish wheel catch of 370 chum salmon was 50% below average.

For the Alsek River, the U.S. commercial catch of 19,600 Alsek sockeye was above the 1984-1993 average. Canadian catches of 1,745 sockeye in the aboriginal fishery was 261 in the sport fishery are 12% and 22% below average, respectively. The escapement of the Klukshu River weir of 15,000 fish was 17% below the 1984-1993 average. The early segment of the Alsek sockeye run was forecast to be strong and fishery performance also indicated this with good catches in the Dry Bay fishery; however escapement counts at the weir were above average. The Klukshu weir counts of 3,200 early run (count through August 15) and 11,800 late run sockeye were 5% above and 21% below the 1984-1993 averages.

The chinook run to the Alsek River was above average. The U.S. Dry Bay catch of 800 fish were over three times the 1984-1993 average. The combined Canadian sport and aboriginal fishery catch of 500 fish was similar to the 1984-1993 average. The 3,700 chinook count through the Klukshu River weir was the second highest recorded since the weir was installed in 1976 and was 70% above the 1984-1993 average of 2,200 fish. The Klukshu River escapement goal is 4,700 chinook salmon. Aerial survey index counts of other spawning systems were average to above average.

The coho run to the Alsek River was believed to have been below average, but present stock assessment programs prevent an accurate comparison with historical runs. The U.S. Dry Bay catch of 4,200 coho was slightly above the 1984-1993 average, while the combined Canadian in-river aboriginal and sport fishery catch of 80 fish was 36% below the 1984-1993 average. Operation of the Klukshu weir does not provide a complete enumeration of the coho into this system since it is removed before the run is over, however, the count of 1,200 coho salmon was 69% of the 1983 -1994 average.