Fish kill dead zones in the gulf are mainly created by the nitrogen and phosphorus enrichment of the Lower Mississippi River. Some species of fish exhibit mass simultaneous mortality as part of their natural life cycle. Fish kill due to spawning fatalities can occur when fish are exhausted from spawning activities such as courtship, nest building, and the release of eggs or milt (sperm). Fish are generally weaker after spawning and are less resilient than usual to smaller changes in the environment. Examples include the Atlantic salmon and the Sockeye salmon where many of the females routinely die immediately after spawning. A
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