Sockeye salmon Sockeye salmon Sockeye salmon ("Oncorhynchus nerka"), also called red salmon, kokanee salmon, or blueback salmon, is an anadromous species of salmon found in the Northern Pacific Ocean and rivers discharging into it. This species is a Pacific salmon that is primarily red in hue during spawning. They can grow up to in length and weigh . Juveniles remain in freshwater until they are ready to migrate to the ocean, over distances of up to . Their diet consists primarily of zooplankton. Sockeye salmon are semelparous, dying after they spawn. Some populations, referred to as kokanee, do not migrate to the
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