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
When a white horse is not a horse be found in the widely known "Happiness of Fish" dialogue in "Zhuangzi" (17, tr. Watson 1968:188-9). Huizi says "You're not a fish [子非魚] — how do you know what fish enjoy?" (denying that Zhuangzi is a member of the class of fish) and Zhuangzi replies "You're not I [子非我], so how do you know I don't know what fish enjoy?" (denying that the individuals Huizi and Zhuangzi are identical). Beyond the inherent semantic ambiguities of "Baima fei ma", the first line obscurely asks "ke hu" "Can it be that …?". This dialogue could be an attempted proof that a white