The Gulf Coast is bracing for an oil slick to come ashore.
With Florida’s valuable ecosystem in danger from drifting oil, there may be some winners and some losers, according to top experts at the University of Miami’s renowned Rosenstiel School of Marine and Atmospheric Science.
Use of dispersants is likely changing the risks. Winners are shorelines and mangroves, where so much of marine life gets its start. Because dispersants now being injected into the oil plumes may help keep oil off the sea surface where it can do greater damage to shorelines and mangroves.
But the dispersant mixes the oil, tainting the water all the way from the surface to the sea floor where, right now, it is likely impacting fish larvae, fertilized eggs that float for weeks or months while developing. Fish include Atlantic Bluefin tuna, grouper, snapper and more.
And it also includes Florida’s famed lobster, where larvae drift from Mexico, Cuba and the Caribbean, around the Gulf and settle in the Keys and elsewhere along Florida’s coast.
The real loser may be coral reefs, according to Andrew Baker, renowned reef expert with UM Rosensteil. Prior to dispersants, they could sit quietly below the floating oil, dodging its lethal impacts. Now the oil stretches – although diluted – down to the sea floor where corals provide homes for vast numbers of marine creatures and sustain the communities of fish.
The oil is toxic to marine life. Several studies, including one groundbreaking study by legendary ocean scientist Jeremy Jackson done in the Caribbean, show just how devastating petroleum can be on delicate reefs that can take centuries to grow.
What is less known is the toxicity of the dispersants. Much has been debated about it. And there’s been much disagreement. One side claiming it’s bad but not nearly as bad as the oil it is mitigating. Others claim it makes the mess more difficult to predict, to manage, and to track.
“The oil is now mixed throughout the water column,” said Baker, “and can potentially interact with the corals in a much denser way.”
With so few studies on the impact of oil and dispersants on marine life, it’s challenging scientists. “And that really means we've added a lot of uncertainty with regards to what's going to happen with the approaching oil,” said Baker.
Beth Babcock, an expert on sustainability on sea life from UM Rosenstiel, said she worries about all fish populations but especially Atlantic Bluefin tuna. Vast numbers of the tuna species, currently on the verge of international protections because of plummeting populations from over fishing, come from throughout the Western Atlantic Ocean to the Gulf to spawn. She fears their spawning grounds may be tainted with oil when they arrive in August.
Published at 6:50 AM EDT on May 18, 2010