The oil might be out of sight, but it shouldn't be out of mind.

The undersea geyser of oil that began with an explosion more than three months ago has stopped but that doesn’t mean the damage is done by any means. While the economic wounds and the oiled birds and sea turtles are easiest to observe and count, the damage to unseen wildlife and the Gulf of Mexico ecosystem remains hardest to comprehend.

NOAA and the US Coast Guard claim they are having a difficult time locating oil sheen on the surface. But, please, don’t let them fool you into thinking the spill has been cleaned up. It’s not and won’t be for some time. In fact, 20 years later, scientists are still seeing the effects of the Exxon Valdez spill. An estimated 100 million gallons of oil spewed out as a result of the Deepwater Horizon.  BP claims to have recovered 37 million gallons and burned an estimated 10 million gallons of oil.  However, they are unable to account for some 50-60 million gallons of oil. This is the equivalent of two Exxon Valdez accidents, which makes it especially odd that until recently NOAA refused to confirm the presence of subsea plumes of oil.

Not only are we failing to account for millions gallons of oil but BP has also rained some 2 million gallons of toxic dispersant on the surface slick.

This dispersant doesn’t clean up the oil. Instead, it bonds to oil, causing it to disperse into smaller droplets and sink it into the depths.  It’s akin to sweeping dirt under the rug.

Actually, it’s much worse than that. Because the dispersed oil is in smaller droplets, it is essentially impossible to remove from the Gulf, and is easily swallowed by even the smallest marine creatures. Scientists will say the oil is now more bio-available. Simply put, dispersant makes the oil more easily ingested by organisms of any size. We can’t be fooled by seemingly clean looking wildlife when the worst is yet to come.

Scientists estimate that for every single bird or sea turtle found oiled, there are another 10 to 100 oiled animals that we haven’t seen. Won’t ever see.  This is only a guess, and probably a conservative one at that. Worse, this only considers birds and sea turtles. No one has any idea how the fishes and whales and sharks are responding. How many unidentified animal victims are slowly being poisoned by oil and dispersant?

As I type this blog, I’m preparing for a trip out onto the Gulf, to work with my friend and colleague Eric Hoffmayer from the University of Southern Mississippi’s Gulf Coast Research Laboratory. We will be conducting an emergency assessment of the whale sharks in the region.

Whale sharks are a globally threatened species and their numbers are on the decline. Although my job title is Whale Program Officer, my job includes protecting and preventing suffering to many other marine animals beyond whales. This includes whale sharks, which are the world’s largest fish. These beautiful and harmless creatures swim through the sea with their mouths agape at the surface grazing on tiny animals known as zooplankton.

These surface-feeding giants are doubly-threatened by the oil spill. First, oil can easily coat their gills as they swim through surface slicks and underwater plumes. Enough oil in their gills, and the sharks will suffocate and die. No one knows how long it may take, could be minutes, could be days, but one thing is certain.  Oil that gets on the gills and prevents normal respiration doesn’t come off.  Since these animals feed at the surface and seem to aggregate in large groups near the spill zone, it may already be too late for many of them.

If the surface oil doesn’t kill them, the dispersant/oil mixture likely will.  Like I said earlier, this dispersant makes the toxins more biologically available, more easily ingested.  As the whale shark consumes more and more poisoned prey it eventually accumulates to such a concentration that it may prove lethal.

What’s most awful is the fact that we will never really know how many whale sharks (and other sharks) have died as a result of the oil spill. Unlike most fishes, sharks tend to sink when they die. We may not see the dead whale sharks, but their deaths will be no less tragic.

IFAW is working with Hoffmayer and others to brainstorm ways to save these beautiful animals. After all, BP’s spill response plan does not take them into account. We’re not going to let them be forgotten and are tagging the few survivors we can find in hopes of piecing together the puzzle of their behavior so that they can be protected properly.  Stay tuned….