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
Fear of fish by what is now called graduated exposure therapy: In contrast, radical exposure therapy was used successfully to cure a man with a "life affecting" fish phobia on the 2007 documentary series, "The Panic Room". Historically, the Navajo people were described as being ichthyophobic, due to their aversion to fish. However, this was later recognised as a cultural or mythic aversion to aquatic animals, and not a psychological condition. The "Journal of the American Medical Association" have published a research paper addressing the fears of eating fish because contaminants, such as mercury may be accumulated in fish. In his autobiography, Italian