Kokanee salmon between 29–40 gill rakers. As a freshwater-based fish, they are much smaller than their sea-going sockeye relatives due to less food availability. Size is the most significant morphological distinction between the kokanee and the Sockeye, but gill raker count can differ from Sockeye salmon as well. The main food source of this fish is plankton. “Kokanee have blue backs and silver sides and unlike other salmon and trout, except chum salmon, sockeye and kokanee lack distinct dark spots on their backs and tail fins. In addition, when compared to other trout, they have finer scales, larger eyes, and deeply forked
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