More bad news has surfaced about the long-term consequences from the 2010 Deepwater Horizon oil spill in the Gulf of Mexico. Scientists say the pollutant can cause severe defects in the developing hearts of bluefin and yellowfin tuna.
The 2010 spawning season coincided directly with the spill, meaning floating embryos were exposed to large surface slicks as oil gushed from the damaged wellhead.
“We know from the 1989 Exxon Valdez spill in Prince William Sound that recently spawned fish are especially vulnerable to crude oil toxicity,” says Nat Scholz, head of the ecotoxicology program for NOAA’s Northwest Fisheries Science Center in Seattle. “That spill taught us to pay close attention to the formation and function of the heart.”
Scientists add that affected fish likely would have died soon after hatching. Additionally, scientists know from previous research that survivors of exposure to crude oil can suffer subtle and transient changes in heart rhythm during development. These changes can permanently impair heart function and swimming ability at later life stages.
“This creates a potential for delayed mortality,” says one scientist. “Swimming is everything for these species.
And evidence that the threat is still out there appeared last June, when a 40,000-pound (20 tons) tar mat was discovered in the surf off Grand Terre Island. Considered hazardous to marine life, the mat reportedly was made of up 15 percent oil and 85 percent sand, shells, and water.
Also, a report last spring revealed the damage done to dolphins, sea turtles, and killifish, a common forage fish at the base of the food web.
“Three years after the initial explosion, the impacts of the disaster continue to unfold,” said Doug Inkley, senior scientist for the National Wildlife Federation (NWF). “Dolphins are still dying in high numbers in the areas affected by oil. These ongoing deaths—particularly in an apex predator like the dolphin—are a strong indication that there is something amiss with the Gulf ecosystem.”
All this is not to say that the fishing is not good along the coast and in the Gulf or that it will deteriorate in the next few years. The truth is that we just don’t know what the long-term consequences will be.
But evidence certainly suggests that fish and other wildlife immediately exposed to the crude oil were harmed and some species continue to be.
That means we haven’t seen the end of this disaster. No one can legitimately declare that damages have been mitigated, or that our wildlife, marshes, barrier islands, and offshore habitat are “cleaned up.”
“It is crucial that impacted regions of the Gulf implement restoration projects that are based upon the best available science, and to spend every single dime of the penalty money from the spill wisely,” says NWF. “That is our priority. The Vanishing Paradise campaign is focused on these goals as we continue our work in all five of the Gulf states. In Louisiana, that means two things:
- Supporting the implementation of the Louisiana State Master Plan
- Ensuring the integrity of the financial mechanisms that fill the gaps between Plan-Funding- and Restoration
“The moral of the story is that the Gulf is still hurting, four years after the largest oil spill in U.S. history. Recovery and restoration are far from complete.”