Widgets Magazine

Research finds Deepwater Horizon spill affects bluefin tuna

Scientists from Stanford and the National Oceanic and Atmospheric Administration (NOAA) recently published a study in Nature: Scientific Reports describing the effect of the Deepwater Horizon oil spill on the Atlantic bluefin tuna population in the Gulf of Mexico.

One of the most significant environmental disasters in history, the 2010 Deepwater spill resulted in the leaking of four million barrels of oil into the Gulf of Mexico. The spill affected 3.1 million square miles of bluefin tuna habitat and occurred during peak spawning season when their vulnerable eggs and larvae are most abundant.

According to a Stanford University Communications press release, Elliot Hazen of NOAA’s Southwest Fisheries Science Center explained, “We know that bluefin tuna face numerous threats in the Gulf of Mexico and the oil spill represents another potential impact during a critical portion of their life history.”

Using data from pre-existing electronic satellite tags, the researchers were able to conclude that at its greatest extent the spill covered five percent of the habitat located within the U.S. Exclusive Economic Zone.

While five percent represents only a small fraction of the entire spawning habitat, earlier studies have demonstrated the significant deleterious physiological effects of crude oil exposure on an already vulnerable bluefin tuna population including causing deformities and death in larvae and eggs.

According to The Times-Picayune, study co-author and Stanford professor of marine sciences Barbara Block said that, “The bluefin tuna population in the Gulf of Mexico has been struggling to rebuild to healthy levels for over 30 years … These fish are a genetically unique population, and thus stressors such as the Deepwater Horizon oil spill, even if minor, may have population-level effects.”

She added, “It is difficult to measure recruitment from the Gulf of Mexico post-2010, as the fish take a long time to enter into the commercial fishery where monitoring occurs, so we remain concerned.”

In NOAA’s press release for the study, Troy Baker, an environmental scientist with the National Ocean Service explained the long term significance of this research, “This new science demonstrates how a combination of animal telemetry [animal borne satellite tagging and tracking] and advanced predictive modeling can help assess injuries to highly migraty [sic] species such as bluefin.”

The researchers warned that further monitoring is required to reveal the spill’s entire effect on bluefin populations.

“Because of their economic and ecological importance, we need to ensure the conservation and protection of Atlantic bluefin tuna on their spawning grounds … We need to ensure maintained — if not increased — monitoring of Atlantic bluefin tuna in the years to come,” Hazen said on NOAA.gov.

 

Contact Zachary Brown at zbrown ‘at’ stanford.edu.