A Connecticut-sized swath of oxygen-deprived waters off the Gulf Coast is a "poster child for how we are using and abusing our natural resources," says one researcher in Louisiana.
In its 30th annual survey, the Louisiana Marine Consortium shows the dead zone has shrunk to about 5,000 square miles and may have stabilized, reports Reuters.
(It previously measured as many as 8,200 square miles.) Still, the Gulf Coast dead zone remains second in size only to one off Finland; it extends along the Louisiana coastline from the Mississippi River Delta to the border with Texas.
Since the 1960s, nitrogen fertilizer, mostly from Midwest cornfields, has been drawn into streams and rivers by rainwater and poured straight into the Gulf via the Mississippi and Atchafalaya rivers, the Times-Picayune explains.
There it feeds algae blooms that turn oxygen into carbon dioxide when it decays—poor conditions for fish and shrimp. Nitrates and nitrogen levels continue to increase, the scientists say.
The EPA has tried to shrink the dead zone to 1,991 square miles since 2001 and isn’t making progress. Environmental groups have sued the agency to force its hand in adopting needed regulations to reduce harmful runoff.
"We keep being told by both regulators and industry that a hands-off approach … is working just fine, but the Dead Zone is clearly not going away," one attorney tells the Times-Picayune.
Louisiana legislators claim the dead zone is natural and want to remove its Gulf waters from the "impaired waters list," reports Nature World News. Activists say similarly harmful algae blooms in both Ohio and Florida prove current efforts aren’t working.
(In other bad news about algae blooms, toxic blooms are so common in Ohio that summertime swimming bans are "routine.")More From Newser