Excerpt:
The Deepwater Horizon disaster on April 20, 2010, was the largest offshore oil spill in U.S. history, releasing an estimated 4.9 million barrels of oil into the Gulf of Mexico over nearly three months. Fifteen years later, the gulf ecosystem shows a complicated picture of both resilience and lingering damage, with some species, like brown pelicans, recovering, while others, like humans, dolphins and deep-sea corals, continue to struggle with long-term health impacts.
Down past New Orleans lies Plaquemines parish, a narrow sliver of land at the tip of Louisiana that reaches southward like a finger pointing into the Gulf of Mexico. Past barbecue joints, a naval base, Baptist churches, white egrets, blue herons, and signs advertising items FOR SALE (live shrimp, empty lots and crawfish), Captain Kindra Arnesen lives with her husband and dog in a tidy brick house that smells like eucalyptus potpourri and home cooking.
“There’s nothing I’d rather be doing than be out on the water fishing, especially offshore. I like to get high up on the boat and look out over the water as far as I can see,” Arnesen told Mongabay while stirring a pot of beans. She has worked small commercial fishing boats out in the gulf for decades. “The only thing I love more is my grandbaby.”
“Before the spill, you could ride out there and everywhere you rode there were bait balls of bonita, blue runners, thread herrings, spinners jumping through them. Everywhere you went it was just a sight,” Arnesen recounted, referring to plentiful schools of small fish and spinner dolphins in the open ocean. “After the spill you could ride a hundred miles and not see a bait ball … It slowly died.”
April 20, 2025, marked the 15th anniversary of what is known as the Deepwater Horizon disaster, when an oil rig operated by BP Exploration & Production exploded and sank in the Macondo prospect, 66 kilometers (41 miles) off the Louisiana coast.
Eleven workers died in the initial explosion, and 17 were seriously injured. What followed became the largest offshore oil spill in U.S. history. Oil flowed from the damaged wellhead nearly 1,500 meters (5,000 feet) below the sea surface for almost three months before engineers finally capped it in mid-July 2010.
All told, an estimated 4.9 million barrels of oil (the equivalent of more than 210 million gallons, or 800 million liters) entered the sea. It slicked 111,000 square kilometers (43,000 square miles) of the gulf’s surface, and smeared more than 2,000 km (1,300 mi) of coast in oil and tar balls.
The response operation was unprecedented in scale, involving several federal agencies, five U.S. gulf states, local governments, dozens of nonprofits and universities, the oil and gas industry, fishing communities, and thousands of volunteers.
BP paid the largest environmental damage settlement in U.S. history, more than $20 billion, and paid out billions more to individuals and businesses.
Fifteen years later, the gulf tells a complicated story of resilience and lingering damage, adaptation and ongoing threats, bureaucratic failures and scientific breakthroughs. The Deepwater Horizon disaster has become both a cautionary tale and a testament to nature’s ability to recover, though many questions remain about its long-term consequences.
“One of the things that a lot of people don’t understand about the gulf is how resilient it is,” Larry McKinney, former director of the Harte Research Institute, part of Texas A&M University-Corpus Christi, told Mongabay. During the spill response, McKinney led a team connecting academic researchers and on-the-ground government agencies.
The Gulf of Mexico’s resilience comes from its unique structure and abundance of life. The loop current from the Caribbean mixes and stirs the water, carrying animals and nutrients throughout the region.
“That whole physical structure is really, really impressive and doesn’t exist anywhere else,” McKinney said. “Then biologically, this is one of the most biodiverse places in the world,” he said. “We’ve got coral reefs, massive fisheries, whales, dolphins. We’ve got everything else here … The only thing we don’t have is ice.
“The problem is that we’ve come to take that [resiliency] for granted,” he added. While the gulf has absorbed the insult and its productivity is bounding back, McKinney said, “The 800-pound gorilla in the room is climate change and how it’s changing things so quickly…”
