Stay with me on this one, because it’s interesting if you don’t know anything about dead zones. The dead zone off the coast of Louisiana is the largest in the US and one of the largest in the world. It’s caused primarily by the Mississippi River dumping agricultural runoff (fertilizer and animal waste) from all the farms upriver into the Gulf of Mexico.
All that fertilizer sends the algae in the Gulf into a feeding frenzy, and they promptly stuff themselves and die. This in turn robs the zone of underwater oxygen – you know, the stuff fish breathe. At scale, it creates a dead zone where living things just can’t exist, and this year’s dead zone is the largest ever.
Knowing that the Mississippi-Gulf dead zone is inevitable each year, a task force has been created to at least try to control it. Thus far it’s been unsuccessful. This year’s dead zone spans almost 9,000 square miles, almost five times the “optimal” dead zone no larger than 1,900 square miles.