Since 2007, with support from the Southern Boundary Restoration and Enhancement Fund, calibration work has been conducted on twenty-five Sockeye populations of various stream types in the Fraser and has led to the development of indices for aerially surveyed Sockeye populations on the following three stream types: i) medium sized, clear streams, ii) medium sized, partially turbid/tannic streams and iii) large sized, clear streams. Although this represents substantial progress, significant gaps still exist on the remaining stream types and lake spawning populations. Calibration work involves the comparison between estimates generated using high precision enumeration techniques (enumeration fences, sonar, and/or mark-recapture programs) and those generated using standard low precision visual techniques. As annual calibration opportunities on target populations are limited, calibration work over the long term will be required to satisfy the data requirements for all stream types. The actual populations to be calibrated will be determined based on in-season estimates of abundance.
Annual stock-specific run reconstructions (catch plus escapements) are required to accurately estimate relative contribution of each stock caught in Northern Boundary Area fisheries. Estimates of national origin of contributing stocks provides the most reliable information currently available to complete these run reconstructions, and are used to evaluate stock-specific productivity and revise pre-season forecasts. While the catch of Nass and Skeena sockeye salmon is only subject to treaty harvest-sharing annexes in the Alaska District 101 gillnet and Alaska District 104 purse seine fisheries, the harvest of these stocks in all fisheries, and their escapements, needs to be estimated in order to calculate the total run and the percentage caught in the annexed fisheries.
This project will complete genetic stock identification (GSI) analysis on sockeye salmon tissue samples collected from the 2016 commercial purse seine fisheries in Districts 101, 102, and 103 in Southeast Alaska. This project is a complement to the ongoing project at the Auke Bay Laboratory for Northern Boundary Area sockeye salmon GSI in Districts 101 and 104, and continuing work by DFO in Areas 3, 4, and 5; and will allow for complete assessment of the catches of Nass and Skeena sockeye salmon in all major Northern Boundary Area fisheries for run reconstructions. Estimates will be provided for up to 3 time strata in District 101, up to 3 time strata in District 102, and over the entire season in District 103, for a total of 1,500 samples analyzed.
Weir counts have been made on the Klukshu River, part of the Alsek River system, by the Department of Fisheries and Oceans (DFO) in co-operation with the Champagne-Aishihik First Nation, since 1976. A mark-and-recapture program ran from 2000 to 2004, and in 2005 and 2006, the Alsek sockeye population was estimated using tissue sample and catch information from the commercial sockeye fishery in Dry Bay as well as the weir counts. By recommendation by the Northern Fund Committee in 2008, a statistically valid sampling strategy that would provide the foundation for reconstructing sockeye and Chinook returns to the Alsek River was completed. Based on this model, it was proposed that funding be provided to analyze sockeye tissue samples collected in the commercial sockeye fishery in Dry Bay (up to 750 per season), to reconstruct the Alsek sockeye runs as described in Gazey’s analysis.
Since 1976, weir counts have been made on the Klukshu River, part of the Alsek River system, by the Department of Fisheries and Oceans (DFO) in co-operation with the Champagne-Aishihik First Nation. In 2007, the weir counts at Klukshu, in conjunction with Chinook catches from the test fishery at Dry Bay, were used to estimate the Alsek Chinook population. The results were encouraging, and by recommendation by the Northern Fund Committee in 2008, a statistically valid sampling strategy that would provide the foundation for reconstructing the Chinook return to the Alsek River was completed. Based on this model, it was proposed that funding be provided to analyze Chinook tissue samples collected in the commercial sockeye fishery in Dry Bay (up to 500 per season), to reconstruct the Alsek Chinook runs as described in Gazey’s analysis. The project was carried out successfully in 2014, but there has not been enough fish in 2015 and 2016.