Published Aug 24 in the NY Times: Unfortunately, the Gulf of Mexico has been in trouble long before the big oil spill that occurred this year in April. However, one of the side effects, it seems, of the oil spill, is that every fish kill is suspected to be related to the BP disaster! Turns out, it is the same old problem that has been haunting the area for years – anoxic ocean waters due to algal blooms responding to an excess of nutrients from a combination of farmland runoff, septic tanks, and lawn fertilizers delivered by the rivers emptying in to the gulf. These are known as Gulf ‘dead zones.’ This article reports that a fish kill (5,000-15,000 fish) at the mouth of a shipping channel in the Gulf was due to hypoxic waters, rather than the oil spill.
Here is a link to the article: https://www.nytimes.com/2010/08/25/us/25latest.html?adxnnl=1&adxnnlx=1282762804-cdTzDkpIY7n9ms9oNBBcFg