A brown pelican coated in oil struggles on East Grand Terre Island, Louisiana, on June 4, 2010. It was the biggest oil spill ever in U.S. waters and remains one of the worst environmental disasters in world history. While the world watched, helpless, oil gushed into one of the planet’s most biodiverse marine habitats for 87 long days. A decade later, many species, such as deep-sea coral, common loons, and spotted sea trout, are still struggling, their populations lower than before. By contrast, a few Gulf inhabitants have shown a robust recovery—among them, menhaden fish and the brown pelican, Louisiana’s state bird. Funds from the Gulf of Mexico Energy Security Act, the Gulf of Mexico Research Initiative—and more recently, the billion settlement between BP and the U.S. federal and state governments—have enabled a legion of researchers to undertake long-term projects investigating how the spill affected Gulfwildlife. But after a decade of close monitoring, Smith feels that she and colleagues have a clear picture of what is going on with that most gregarious of cetaceans, the bottlenose dolphin—and it’s grim. Ten years out, Smith is also seeing higher rates of reproductive failure, lung disease, heart issues, impaired stress response, and death in bottlenose dolphins. Interestingly, says Smith, these symptoms mirror the most common health issues faced by another large mammal exposed to the oil spill: humans. Two recent studies, both published in 2018, found impaired lung and heart function and strained breathing, respectively, among cleanup workers and U.S. Coast Guard personnel who had been in contact with the oil. “We're in this space together, and there's a lot to learn from that.” Kaitlin Frasier remembers the day in 2010 that her Ph.D. adviser told her he thought she should focus her career on the recent Deepwater Horizon spill. Today, she’s an assistant project scientist at the Scripps Institution of Oceanography at the University of California, San Diego, and has spent the past decade listening for signs of life in the Gulf—namely, the clicks and clacks of echolocating marine mammals. In part, that’s because scientists knew little about the habits of many deepwater marine mammals before the spill, so have trouble detecting changes from current data. Marine mammals are important indicators of the overall health of the ocean, so studying them can tell scientists a great deal about their environment. Peter Etnoyer, a marine biologist at the National Oceanic and Atmospheric Administration’s (NOAA) Hollings Lab, studies deep-sea corals. The ones we found to be injured are on the order of decades to hundreds of years old.” (Learn how the Gulf oil spill was even bigger than thought.) And because they exhibit growth rings like those of trees, corals act as “little environmental monitors, recording conditions over time,” Etnoyer says. Leatherbacks and Atlantic hawksbills roam offshore waters, while loggerhead, green, and Kemp’s ridley sea turtles frequent near-shore habitats. A 2017 study estimated that of at least 402,000 sea turtles exposed to oil during the spill, 51 percent were Kemp’s ridleys, the smallest and most critically endangered species. The move resulted in new protections for nesting beaches in Texas and Mexico, and requirements that shrimp fisheries in the Gulf use excluder devices to prevent the reptiles from being captured in trawls. That statistic includes common loons, northern gannets, double-crested cormorants, royal terns, Wilson’s plovers, black skimmers, and seaside sparrows, to name a few. The project was completed this past February and is being hailed as a success for brown pelicans, with up to 20 percent of the state’s population already nesting there,along with great egrets, roseate spoonbills, royal terns, and tri-colored herons. Recent research that tested 2,500 different fish across the Gulf found evidence of oil exposure in all 91 species sampled, suggesting that the impacts of the spill are widespread and ongoing. It could take decades to understand how oil affects the next generation of whales, coral, sea turtles, birds, fish, and more. In May 2019, the U.S. Department of the Interior rolled back safety regulations to offshore drilling that were put in place to prevent a repeat of the Deepwater Horizon spill. At the same time, there have been expansions of Gulf protected areas, like the Flower Garden Banks National Marine Sanctuary. Meanwhile, Kaitlin Frasier will remain at her desk, listening for the chirping sounds of Risso’s dolphins and the long, low vocalizations of sperm whales.
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