While most of our recent conversation about BP’s deepwater drilling disaster has been focused on the RESTORE Act, and successful efforts to legislatively direct the eventual Clean Water Act fines to Gulf ecosystem and economic restoration, new scientific studies are an important reminder that BP’s crude and corexit continue to have untold impacts on our Gulf.Graduate student Jessica Henkel gently removes a Dunlin (Calidris alpina) out of a mist net in Waveland, Miss. (Photo by Ken Murphy, courtesy of Tulane Public Affairs))Researchers out of Alabama have shown convincingly that dispersant and oil will throw a significant curve ball at the Gulf foodweb. Their study replicates the real-world situation BP created two years ago, and documents bacteria increases with a subsequent decrease in plankton production, creating an energy bottleneck which could have troubling repercussions for the massive amount of sea life which depend ultimately on plankton for their food.While this bottleneck is unlikely to be replicated Gulf-wide, it is certainly a concern for hot spots such as Barataria Bay, and could help explain the documented drop in shrimp catch in the area. The research also underscores just how little we understand about dispersants, and their effect on the ecosystem, which is why the Government Accountability Office recently called for more targeted research on marine impacts and the Arctic (currently in the oil companies’ sights).GRN and our partners continue to press the EPA to get on with dispersant testing and to develop more specific and protective rules for their application. Studies such as this should play a prominent role in that rule-making. Watch this space for updates on that effort shortly.The second study that caught my eye was out of Tulane University and focused on BP’s impacts on shorebirds. Nearly 10% of the shorebirds trapped by the researchers in the Northern Gulf coastal area from the fall of 2010 through the spring of 2011 were visibly oiled, with non-visible affects possible as well, such as the ingestion of tarballs or contaminated prey. The Mississippi River delta wetlands are critical flyway habitat for at least 28 species of migratory shorebirds, and over a million birds. The study looks at how BP’s oil may affect the birds, and matches up well with reports which document BP’s oil on nesting white pelicans in Minnesota.The overall message of this recent research is that we’re not out of the woods yet. As a Florida researcher put it: People want to say the Gulf dodged a bullet. Well that’s not true. The Gulf got shot, but we’re still trying to figure out how bad the wound is.The Exxon Valdez must serve as a cautionary tale for our efforts to hold BP accountable. After Exxon had already written a check for their ecosystem damage, the herring fishery of Prince William Sound collapsed commercially, four seasons after the oil spilled. While researchers make a compelling case that sub-lethal impacts from Exxon’s oil were the ultimate cause of the collapse, Exxon has never paid for that impact.As federal and state natural resource agencies negotiate with BP over the cost and efforts to restore the Gulf they damaged, they would do well to keep that in mind. We can’t settle on the Natural Resource Damage Assessment until we have a much better idea of the damage. Right now we need to focus efforts on making the Gulf as robust and as resilient as possible, and decreasing our impact on critical pieces of the ecosystem, such as our efforts to protect adult spawning bluefin tuna.It’s good that BP committed a billion dollars to early restoration efforts, but with such significant questions remaining, we can’t close the books on Gulf recovery and restoration.Aaron Viles is GRN’s Deputy Director. You can follow him on twitter here.