Last month’s blowout of British Petroleum’s Deepwater Horizon oil well — which caused the US Commerce Department to decree today (25th May) that fisheries in three states bordering the Gulf of Mexico are official disasters — is likely already impacting the Gulf’s microscopic denizens, which will, in turn, have long-term effects on commercially important species such as fish and shrimp, scientists say.
Images of oil-soaked sea gulls and tar coated turtles, which typically follow major oil spills, are starting to materialize in the Gulf, but bacterial populations are likely to boom in response to the release of millions of gallons of oil, Monty Graham, biological oceanographer at the Dauphin Island Sea Lab off the coast of Alabama, told The Scientist. Bacteria could benefit from the oil spill, Graham argued, because some bacterial species and lineages view a massive oil spill as a veritable cornucopia of delicious hydrocarbons, not a catastrophe. The boon to bacteria most likely has ramifications that will ripple throughout marine food webs in the Gulf, especially at prominent nodes where commercially important species such as fish, crabs, and shrimp, reside. What those ramifications are, however, remain as murky as the huge plumes of oil recently discovered hovering just below the surface of Gulf waters. Researchers who study microbial and planktonic ecosystems in the Gulf of Mexico are anxiously anticipating the effects of what may be the biggest oil spill ever. Recently uncovered evidence of oxygen depletion near those plumes (an indication that bacterial respiration is occurring en masse) indicate that a bacterial bloom is ramping up.