Gulf of Mexico : Fertilized to Death

Page - July 8, 2008
The Dead Zone in the Gulf of Mexico (US) - By Henry Steinberg: First came Hurricane Katrina, taking their houses. Now the Dead Zone is taking their hope. The shrimpers on Grand Isle, Louisiana, are hit hardest by an environmental disaster that summer after summer is killing all life in a vast area of the Gulf of Mexico.

"Everything around here is dead. I've got crabbers picking up crab traps; all the crabs are dead. Shrimpers don't pick up a single shrimp. Right along the beach here, you find shrimp, fish and eels that are dead," Dean Blanchard said. For five generations, his family has been in the seafood business in Grand Isle, a little island in the Gulf of Mexico. He is the largest buyer of shrimp from the region.

He started noticing changes in his catch about seven or eight years ago, when the landing of seafood on Grand Isle dramatically declined. Ten years ago, he was buying 80,000 to 100,000 pounds of seafood a day. Now he is lucky to get 15,000 to 20,000 and some days it's as low as 2,000 to 3,000 pounds. Blanchard knows why: "We are the garbage dump of America. Whatever you throw in the river is gonna end up down here."

And he is right. The underlying cause for his problems is nutrient overload from the Mississippi River. The constant stream of nutrients, primarily nitrogen, stimulates plankton production in the Gulf. After death, the plankton decomposes, which requires large amounts of oxygen. The more nitrogen available, the more plankton will grow and ultimately oxygen concentrations decrease below critical thresholds for most living organisms.

Poissons morts d'asphixie sur les rives d'une baie.

[Copyright : Kerry St. Pe]

The lack of oxygen kills marine life, creating an area where no animal life can exist - a Dead Zone. The biggest Dead Zone ever came in 2006 in the Gulf of Mexico. It was larger than 20,000 square kilometres, and is due to grow.

Scientists studying the situation in the Mississippi and the Gulf of Mexico are clear who is to blame. "Most of the nutrients that get to the Gulf come from agricultural activities," says Dr. Nancy Rabalais, Director of Louisiana University's Marine Consortium and an expert on the Dead Zone.

According to one of her recent publications, 67 per cent of the nitrates in the basin are of agricultural origin, from the vast farming areas all along the Mississippi River.

The biggest problem is the overuse of nitrogen fertilizers in industrial farming. Crops need nitrogen to grow, and much of the increases in crop yield in recent decades are due to supplying additional nitrogen to the soils from organic or synthetic fertilizers. But the intensification of agriculture has lead to a general practice of applying more than the crops need. The use of fertilizers has increased from 11 million tonnes of nitrogen in 1960 to 91 million tonnes in 2004.

Much of the nitrogen that is not used by the plants runs off into waterways or evaporates into the atmosphere. Lakes, rivers and oceans around the world are exposed to ever increasing amounts of nitrogen, which cause harmful algae blooms and dead zones. In 2006, the United Nations Environmental Programme estimated that the number of dead zones has increased worldwide from 150 in 2004 to 200 in 2006 - a 30 per cent increase in just two years.

Dr. Rabalais points out that the critical step to fight the Dead Zone in the Gulf of Mexico is to reduce the amount of fertilizer used in the American Midwest. According to her, there are lots of ways this can be done, such as by precision fertilizing to determine the exact amount of nitrogen the crop needs, or by creating buffers between streams and crops comprising trees or uncultivated land to filter out most of the fertilizers and pesticides. She added that fertilizing crops in spring rather than in winter would help avoid washing away most of the fertilizer before planting.

But the outlook for the shrimpers on Grand Isle is bleak. It is estimated nitrogen use in the Mississippi has to be reduced by 35 to 45 per cent within the next decade, just to reduce the Dead Zone to below 5,000 square kilometres. Considering the resistance of the powerful fertilizer industry lobby and the massive expansion in corn acreage following the current biofuel boom in the Midwest, this reduction target is substantial. It would be a major undertaking just to maintain the status quo against the increase in corn growing.

But for Grand Isle, the status quo is already unbearable. Until last year, the fishermen on Grand Isle could still find pockets of life within the Dead Zone. Surface winds, currents, air temperatures and other factors meant the Zone shifted slightly. But in 2007, for the first time, the Zone was so big that for some weeks in summer, there was no such movement and there was no way to go for the fishermen to catch shrimp in the area.

Only a fierce storm could bring relief, by mixing oxygen-rich water into the Zone area. Storms the islanders used to loath are now seen as a way to relieve their misery. As Blanchard put it: "I find myself praying for hurricanes to stir this water up so we can get back to work. And look, I lost everything I had in the last hurricane; it's kind of hard to pray for hurricanes."

The only way out for Harry Chemarie and the shrimpers on Grand Isle is fertilizer reduction programs along the Mississippi River basin. Legally binding upper limits on fertilizer use must be established and enforced, to avoid any loss of fertilizer to air and water and any further deterioration of marine life in the Gulf of Mexico.

Harry Chemarie, shrimper on Grand Isle

Harry Chemarie grew up shrimping on Grand Isle. At the age of 12, he had his own boat. "I used to catch so much shrimp, I would jump overboard in water up to my knees, pull the bag and just pour the shrimp into the boat."

He has been able to raise four children as a shrimp fisherman on Grand Isle, and one of his sons is also a fisherman.

But since the arrival of the Dead Zone, his business is dying. In 2007, it often did not pay for the shrimpers on Grand Isle to take their boats off the docks. One night that summer, his son trawled for five hours, just to return with a meagre 20 pounds of shrimp. At US$3.80 per pound, it did not even pay for the fuel he used.

With such low catches, Harry and his son had to let their deckhands go. "Plenty of the fishermen have tied their boats up and got jobs working with contractors. Some have left the business altogether."

Harry can't help but have a negative outlook. Although he wishes for a better price for the few shrimp that are being caught, and a lower price for the fuel he must use, he can't imagine the situation improving. "How you gonna stop it? It's already out there. It's pouring out the two rivers we got".

The only way out for Harry Chemarie and the shrimpers on Grand Isle is fertilizer reduction programmes along the Mississippi River basin. Legally binding upper limits on fertilizer use must be established and enforced, to avoid any loss of fertilizer to air and water and any further deterioration of marine life in the Gulf of Mexico.