Author: Julia Whitty
Source: Mother Jones
January 9, 2013

Results are in from the first controlled laboratory tests on how Deepwater Horizon oil and the dispersant Corexit® 9500 affect coral larvae. Conclusion: Baby corals of at least some species are likely to be killed when exposed to oil and are especially likely to die when exposed to dispersants. The results have just been published in the science journal PLOS ONE.

Coral larvae are delicate little beings that drift away from their parents (see video below) to settle on near or distant reefs. The study from Mote Marine Laboratory scientists focused on two coral species—mustard hill coral  (Porites astreoides) and mountainous star coral (Montastraea faveolata)—from the Florida Keys, an area not directly impacted by the spill. Both species are common reef builders in the Gulf and the Caribbean.

The researchers tested larvae in water containing 1) the dissolved components of Deepwater Horizon oil from the source; 2) weathered oil; 3) the dispersant Corexit® 9500; and 4) the combined oil and dispersant. They monitored the coral larvae for 72 hours at different concentrations of each solution, and tested how the mountainous star coral larvae fared in solutions that were slowly diluted over 96 hours.

To read the full text of this article, click here.