Marine Biologists have issued a grim forecast for Gulf shrimpers and fishermen in the wake of the BP oil spill: the 2011 “Dead Zone” in the Gulf, they predict, will likely be the largest on record, choking some species of sea life and hindering others from properly migrating and developing. The implications of a super-size dead zone, estimated to grow as large as the size of Delaware and Maryland combined, could be huge for many Gulf Coast workers already struggling to rebound after BP’s oil spill harmed vital shrimping grounds.
Dead zones are areas of inhospitable, oxygen-deprived water that suffocate some forms of sea life and drive out others. In the Gulf of Mexico, dead zones form when agricultural fertilizers, animal and municipal waste, and other contaminants surge from the Mississippi River watershed into the Gulf. In the warm, relatively shallow Gulf waters, this influx of “nutrients” feeds marine algae, resulting in unnaturally gigantic blooms.
This algae, or phytoplankton, also consume much of the water’s oxygen when feeding on the contaminants. Large amounts of organic matter form in this process, then sink to the bottom of the Gulf where bacteria go to work breaking it down, all the while consuming even more oxygen. The result is a hypoxic (oxygen-starved) area void of life.
Dead zones have occurred in the Gulf of Mexico for the last 40 years or so, varying in size from year to year but generally growing in severity. Scientists estimate the 2011 dead zone will be between 8,500 and 9,400 square miles, about 5 to 10 percent larger than 2002 dead zone – the largest dead zone in the Gulf to date.
Dr. Nancy Rabalais, executive director of the Louisiana Universities Marine Consortium, has studied the Gulf’s dead zones since 1985. She predicts that the dead zone forming this year will expand further out to sea and more westward toward Texas. Shrimpers will have to travel further and further beyond the hypoxic zone for their catch, spending more time and fuel for smaller catches.
While the BP oil spill isn’t directly responsible for the Mississippi River dead zone, the 200-million-plus gallons of oil and the millions of gallons of toxic chemical dispersants that BP dumped into the Gulf have caused a dead zone of their own. Scientists have found several square miles of Gulf sea bed blanketed by oil untouched by hungry microbes.
Pictures taken during submarine excursions to some of the oil-choked areas showed crabs, starfish, coral, tube worms, and other creatures smothered to death under thick blankets of oil. Highly toxic gases released from the well and noxious soot from the burning of oil on the surface have deepened the devastation. The effects of Corexit, the chemical dispersant used by BP to break the sludge into smaller particles, are still largely unknown and widely feared in the scientific community.
Beasley Allen is currently investigating hundreds of claims related to the April oil spill disaster, which affected the entire Gulf Coast region. Called the worst environmental disaster in U.S. history, it may be years before the true scope of damage is known. The spill negatively affected industries ranging from commercial and recreational fishing to tourism and economic development, and took a toll on the health and well-being of people who live and work along the Gulf and depend on it for their livelihood.