Hello everyone!
When we think about marine pollution, one of the things that we will think about would be oil spills. Therefore, I would like to focus on discussing the Gulf oil spills that occurred in 2010.
What is the Gulf oil spill?
On April 20, 2010, an explosion occurred at the BP Deepwater Horizon oil rig which caused the release of over 130 million gallons of crude oil into the Gulf of Mexico. It was the biggest oil spill in US waters and one of the worst environmental disaster in world history as oil gushed into one of the planet’s most diverse marine habitat for 87 days straight (Meiners, 2020). 11 rig workers lost their lives as a result and so did unknown millions of marine mammals, sea turtles, birds, and fish. To get a better idea of the timeline of events following the explosion, do watch this video by TIME which provided a very concise and summarized version.
2 days after the incident, BP applied 1900 gallons of oil dispersant to mitigate the growing slick on the surface of the water by breaking them up causing them to sink. More dispersant was applied even days after totaling up to 830,000 gallons of dispersants applied. 8 days after the incident, the coast guards used controlled fires to burn the oil on the surface to slow the spread. This point also brings me to my previous post on how smoke can affect marine mammals. Scientists later discovered that the application of the dispersants has resulted in a massive cloud (~10km wide and ~35km long) of beaded oil that hover mid-depths.
Though the application of dispersants seemed like a good idea to get rid of the oil on the surface, it just caused the oil to spread further under the surface that was even harder to track. This threatened a vital underground ‘rainforest’ known as the DeSoto Canyon which was around 32km away from the wreck site. The upwelling of nutrient-rich water at the DeSoto canyon makes it a densely fertile area that is very welcoming for fish, coral, and other living things (Kluger, 2010). The dispersants are a cauldron of chemicals and about one-third of which are proprietary, which means even BP was unaware of what they are spraying exactly. But it is the surfactants, lipoprotein used in soap to reduce the surface tension of liquids, that is the most active ingredient. By reducing the surface tension, it breaks the oil from slick into droplets. The smaller the breakdown, the easier it becomes for creatures of any size to ingest the oil and surfactant themselves (Kluger, 2010). It may look good on the surface but the oil was just made even more available to the creatures in the ocean. The effect on ocean life could be devastating and it will by no means be limited to the fish themselves. There could be toxic effects on the fish larvae and also long term impacts that could cascade up the food web.
Even after 25 years of the Exxon Valdez spill, the oil is still present on the beaches. The Gulf oil spill is worse than the Exxon Valdez spill, and how long it would take for ecosystems to recover still remains a huge question. Though there are a few Gulf inhabitants like the menhaden fish and the brown pelican which has shown a robust recovery (Meiners, 2020), it is still hard to determine the impact on longer-live sea species like the mammals.
In this post, I gave a brief overview of the BP Deepwater Horizon oil spill and in my next post, I will start to discuss the impacts of the oil spill on animals.
That brings me to the end of this post.
See you guys soon!
References
Kluger, J. (2010, May 29). Gulf Oil Threatens an Underwater ‘Rain Forest’. Retrieved November 06, 2020, from http://content.time.com/time/health/article/0,8599,1992812,00.html
Meiners, J. (2020, April 17). Ten years later, BP oil spill continues to harm wildlife-especially dolphins. Retrieved November 06, 2020, from https://www.nationalgeographic.com/animals/2020/04/how-is-wildlife-doing-now–ten-years-after-the-deepwater-horizon/
