Gulf of Mexico
The Ecologist

Shrinking the Gulf Coast 'dead zone': Part I

Shrimpers want to explain first-hand the impact of large-scale farming on their lives, the environment, and ecology.


The Ace of Trade shrimp trawler motored toward Dean Blanchard’s dock early this summer and winched its nets into storage. Blanchard’s workers, strengthened by a lifetime at sea, worked shirtless in the humid summer air.

It was the beginning of hurricane season, and so far 2019 had been the wettest year in US history. With cigarettes in mouths, they vaulted aboard the shipto shovel knee-high piles of fish off the fiberglass deck and into holding tanks, where they awaited the 12-inch-thick, semi-translucent pipes that’d suck them into the warehouse.

This photo essay was written and photographed by Spike Johnson in partnership with the Pulitzer Center.

Blanchard has been in business for 37 years, and is one of the largest shrimp suppliers in America, distributing off the barrier island of Grand Isle in the Mississippi River Delta. He’s a squat man with a boxer’s nose, a soft talking Cajun with the gravelly voice of a lifetime smoker. He fought hard for his livelihood in the early years, when tensions ran high between American shrimpers and newly arrived Vietnamese refugees.

In the 90s, Blanchard said that American shrimp boats would sometimes pull alongside his dock opening fire with automatic weapons, angry at the market competition Blanchard encouraged through his dealings with Vietnamese shrimp fishermen. He said he would always shoot back.

In 2010, Blanchard graduated to political battles with the BP Deepwater Horizon disaster, a spill that sent 4.9 million barrels of oil into his fishing ground. Blanchard’s business took a hit. He later told reporter Julie Dermansky that he estimated his business was worth 15 percent of what it was before the spill. He testified in Congress and began appearing on national news shows to lobby for his industry.

But increasingly, Blanchard and other Gulf Coast fishermen find themselves skirting a different type of pollution, a threat to the seafood industry and ocean biodiversity that’s unrelated to oil, and much harder to fix.

“Sometimes we'll get thousands of pounds of shrimp a day, then the next day everything’s gone,” Blanchard said. “When the dead zone comes, it just kills everything.”

The Gulf of Mexico dead zone — a large, oxygen-deprived swath of water tha  is a result of nitrogen and phosphorus fertilizers from farms in the Midwest that have concentrated off the coast of Louisiana and Texas. The chemicals encourage the growth of algae, which suck up oxygen choking marine life. Escaping fish are forced to migrate out of natural habitats.

This year, the dead zone measured 6,952 square miles  — about the size of New Hampshire, much larger than the 5-year average of 5,770 square miles —  according to the National Oceanic and Atmospheric Administration. Studies by the journal Science state that the global area of dead zones has quadrupled since 1950, driven by a growing human population, and an increase in factory farming methods.

The Mississippi River basin is the country’s largest drainage basin, and one of the largest in the world. Likea topological funnel between the Rocky and Appalachian Mountains, it directs 41 percent of America’s water, along with its contaminant loadtoward the Delta, and America’s most productive fishing grounds.

Climate factors compound the growth of the dead zone, with increased rainfall contributing to field erosion and fertilizer movement. Last May, the United States Geographic Society commented that the output of the Mississippi River, and its distributary, the Atchafalaya River, were 67 percent above the long-term average between 1980 and 2018, estimating that this larger-than average river discharge carried 156,000 metric tons of nitrate and 25,300 metric tons of phosphorus into the Gulf of Mexico in one month alone, 18 percent and 49 percent above long-term averages, respectively.

Fishing in the Gulf has become unpredictable. As the dead zone shifts and grows, ocean life are pushed into areas where they wouldn’t normally be found. Commercial and recreational fisheries depend on species that spend time within the shallow waters overlapping the dead zone. Normally they would move from inshore nurseries to offshore spawning grounds, but hypoxia blocks their migration, leading to erosions of natural habitats and declines in mating.

A study by Duke University found that hypoxia in the Gulf drives up shrimp prices generally, impacting consumers, fishermen and seafood markets. Fishermen catch smaller shrimp and fewer large ones, making small shrimp cheaper and large ones more expensive. The total quantity of shrimp caught remains the same, but a drop in popular large shrimp leads to a net economic loss.

“So far we have 68,000 pounds a day for the month. Normally we average about 90,000 pounds a day,” Blanchard said.

That decreased volume comes even with improved equipment — new evolutions in radar, winches, and net technology that to keep the amount of fish abreast of ecological changes.

Read the full Ecologist article . . .