Sockeye salmon decline from the recent (1993) historical cycle peak of 23,631,000 and the return abundance was the lowest in over 50 years. The reasons for this (former) decline remain speculative. According to a consortium of scientists assembled to review the problem, the decline highlights the uncertainty in forecasting salmon returns. After the low returns, the Government of Canada launched a formal inquiry into the decline, the Commission of Inquiry into the Decline of Sockeye Salmon in the Fraser River. The Commission has been tasked with investigating all the factors which may affect Fraser River sockeye salmon throughout their life cycle. According
Environmental issues with salmon 59 years of catch and escapement data of Bristol Bay sockeye to determine age and size at maturity trends attributable to the selectivity of commercial gillnet harvests. The study found that the larger females (>550 mm) of all age classes were most susceptible to harvest. The study suggests that smaller, younger fish were more likely to successfully traverse the gillnet fishery and reproduce than the larger fish. The study also found that the average length of sockeye harvested from 1946–2005 was 8 mm larger than the sockeye who escaped the gillnet fishery to spawn, reducing the fecundity of the average