The 2010 Deepwater Horizon oil rig spill released 200 million gallons of oil into the Gulf of Mexico, covering 100,000 kilometers, including 1,000 linear miles of coastline. Luckily, the coastlines of Florida, Mississippi, Louisiana, and Alabama were spared by the use of chemical dispersants to hold back the spill.

Dispersants do not get rid of oil, but instead speed up the natural dispersion of it, meaning that it’s still out there, generally settling to the ocean bed or being ingested by aquatic organisms. It is for this reason that the use of dispersants was controversial then, and remains so now.

Oil Spill

A number of studies on the effects of the spill have been undertaken, but so far information is still scant. Two recent studies by researchers from Florida Atlantic University have given us a bit more information. According to the studies, oil from Deepwater Horizon has affected every metric by which they measure the health of certain organisms in the Gulf ecosystem. These organisms, chiefly oysters, conch, shrimp, coral, and plankton, form the basis of ocean, and especially coastal, food webs.

The oil has impacted the fertilization success, development, survival, and swimming behavior of various organisms. One study, focused on oysters, has found that oil has affected the populations of those creatures in the Gulf, and that it’s impact depends on the life stage of a creature when impacted.

Oysters only have a lifespan of about two years, but that means they reproduce quickly and often, at least normally. Fishers report that oyster populations have not returned to pre-spill levels, meaning that their ability to breed has been influenced by the spill. Likewise, oil and dispersants have affected the growth and motility of at least two species of algae that grow in the Gulf of Mexico.

These creatures are important to the overall ecology of the Gulf of Mexico, and reductions in their populations can impact creatures throughout the entire food-web.