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
Fish products Fish products Fish and fish products is consumed as food all over the world. With other seafoods, it provides the world's prime source of high-quality protein;14–16 percent of the animal protein consumed worldwide. Over one billion people rely on fish as their primary source of animal protein. Fish and other aquatic organisms are also processed into various food and non-food products. In Ancient Roman society, garum, a type of fish sauce condiment, was popular. Sharkskin and rayskin which are covered with, in effect, tiny teeth (dermal denticles) were formerly used in the same manner as sandpaper is in the modern