Sockeye salmon subordinate males. Aggressive interactions between females only last one or two charges and/or chases. The intruder retreats and the spawning female settles back in her redd. These acts of aggression are important in terms of reproductive success, because they determine the quality of the nest site the female obtains and access to males. Competition for food or space while the salmon are in their lake residence period can exist. This happens when there is a more populous class of young sockeye or when there are multiple classes present. It can also happen when resources are in short supply. Interspecific competition
Fish disease and parasites mid-1980s, in particular, an overview report which states that "the fish that have the longest fresh water residence time as juveniles have the most noticeable infections. Hence in order of prevalence coho are most infected followed by sockeye, chinook, chum and pink." As well, the report says that, at the time the studies were conducted, stocks from the middle and upper reaches of large river systems in British Columbia such as Fraser, Skeena, Nass and from mainland coastal streams in the southern half of B.C. "are more likely to have a low prevalence of infection." The report also states "It