Gulf of Mexico study finds steep decline in deep-water marine life after 2010 spill
Researchers found far fewer marine animals in a surveyed part of the Gulf in the years after the Deepwater Horizon disaster, though the area had no pre-spill baseline.
Marine animal numbers fell by about 60% in a deep part of the Gulf of Mexico surveyed after the 2010 Deepwater Horizon oil spill, according to a new study reported by The Associated Press on October 20. The finding raises concern about damage in a part of the Gulf that is difficult to observe, but researchers had no survey of that area from before the spill.
What the Gulf surveys found
Researchers surveyed the area in 2011 using six sets of nets at different depths and acoustic sonar, AP reported. They returned to the same location with the same equipment three and a half years later. In that repeat survey, marine life was between one-third and one-quarter of its 2011 level. The comparison documents a steep decline at the surveyed site; it does not measure animal numbers across the entire Gulf.
The study focused on the ocean’s twilight zone, between the sunlit surface and the darkest depths. Creatures living there are food for animals nearer the surface, including dolphins and whales, AP reported. Study lead author Tracey Sutton, a biological oceanographer at Nova Southeastern University, said the region had not been studied before the 2010 spill. That missing baseline limits what the surveys can establish about conditions before oil entered the Gulf.
Sutton said the researchers examined temperature, oxygen supply and food as possible explanations for the decline and found that none varied with it, according to AP. Those checks strengthen the concern raised by the surveys, while the absence of a pre-spill count leaves the spill’s precise contribution uncertain. The BP-operated well failed in 2010 and released an estimated 134 million gallons of oil, AP reported.
Earlier Gulf whale research adds context
A separate [2024 study of toothed whales](https://www.nature.com/articles/s43247-024-01920-8) found decade-scale density declines in seven of eight monitored species groups, including a drop of up to 83% for beaked whales. Its authors said the declines were not conclusively linked to the oil spill, although their broad pattern in time and space was consistent with its effects. Their monitoring used five long-term stations from 2010 to 2020; how well those stations represent wider Gulf trends remains under investigation.
Kaitlin Frasier, a Scripps Institution of Oceanography scientist who was not involved in the new study, told AP that the difficulty of seeing these deep regions can obscure damage. Dalhousie University marine scientist Boris Worm, also outside the study, called the apparent impact vast and sustained. Worm said the findings should inform discussions about deep-sea mining and increased oil drilling in deep water.
Read in depth: World
China’s social insurance push draws backlash over wages and contribution costs
Workers are questioning the cost of social insurance as China prepares new penalty standards for employers who fail to pay contributions from November 1.
Kumanjayi Little Baby review finds widespread NT child protection failures
An independent review found delayed responses and gaps in safety checks before the five-year-old’s death. The Northern Territory government accepted all 45 recommendations.
Sources and context
- Marine life dramatically declined in Gulf of Mexico in years after BP oil spill, study findsThe Associated Press, republished by Phys.org
- A decade of declines in toothed whale densities following the Deepwater Horizon oil spillCommunications Earth & Environment / Springer Nature
AI-assisted article checked against the listed sources. NewsJaws did not conduct interviews or attend the reported events.