Portal de Periódicos da CAPES

Speak up now – don't wait for the jury!

2011; Wiley; Volume: 9; Issue: 7 Linguagem: Inglês

10.1890/1540-9295-9.7.367

1540-9309

Jacqueline Savitz, Matthew Huelsenbeck,

Turtle Biology and Conservation

On April 20th, 2010, the phones at Oceana's headquarters in Washington, DC, began to ring off the hook. Journalists were calling, mostly asking the same question – “What will be the impacts of the Gulf of Mexico oil spill?” – as if our scientists could simply plug some facts into high-powered computers and provide a clear answer. Of course, nobody can do that; even now, more than a year later, there are too many factors to consider. Additional information about the rate and duration of oil exposure, as well as synergies with dispersants and other chemicals, is still required. The scientific community doesn't fully understand the impacts of the spill on dissolved oxygen conditions or organisms' reproductive cycles, or even the influences of fluid dynamics. Will there be negative consequences for larval recruitment or changes in food availability? What about competition and predation rates? The extent of toxic impacts will also depend on the baseline health status of marine populations – something that is unknown for many species. Finally, the results from post-spill research may not be made public because of ongoing legal issues.The jury is still out. However, just because our knowledge base isn't complete doesn't mean that we can't interpret the situation for the public. We can still attempt to identify the ecological vulnerabilities and the breadth of the likely effects. As it stands, many people believe that the spill's impacts were minimal and are now in the past, in part because of our limited ability to prove effects. But we know that there may be long-term impacts, and there's a lot we can say while still being clear about the limits of the science. First of all, the oil posed major risks to marine populations, such as endangered sea turtles and Western Atlantic bluefin tuna (Thunnus thynnus), that were already vulnerable. Atlantic tuna stocks have been fished down to 10% of 1975 levels and are listed by the International Union for Conservation of Nature as “critically endangered”. Even under the best of circumstances, both tuna and sea turtles require several years to rebuild their populations, but in a stroke of bad luck, the spill occurred during the tuna spawning and turtle nesting season. Will the young survive? Will the adults suffer from reproductive deficiencies? Will survival to reproductive age be affected? We simply don't know, and may not know for some time. But it's quite possible that the recovery of at-risk populations will be slowed or even prevented by the spill. More scientists should talk publically about these types of potential spill impacts. It's also important to be clear about what the absence of an obvious effect actually means. Some believe that marine wildlife were unaffected by the oil because large numbers weren't seen washing ashore. Relying on direct observation alone often results in underestimations of the full impacts. Historical data show that the number of marine mammal deaths from the Deepwater Horizon spill may be up to 50 times higher than the number of carcasses officially recorded. We need to explain to the public and to decision makers that the impacts are greater than what might be directly observed, even if we're not capable of actually counting them. Now, like no other time in history, scientists are being relied upon to help people understand what is being done to the planet, and we're doing a miserable job of it. If we don't learn how to interpret and correct these man-made ecological problems, the ecosystems we depend on are in big trouble. We have to do this in the face of opposition from the industries responsible for creating such messes in the first place. We have to do it in spite of the quirkiness of the media and even though it may not fit nicely within the scientific method. While we can't simply generate all the answers automatically via computer, it's important that we paint a general picture – with all its knowns and unknowns – to help clarify the risks of continued offshore drilling to the public. It's safe to say that 172 million gallons of oil released in the Gulf, combined with gaseous hydrocarbons and chemical dispersants, is definitely not good for wildlife. It's also safe to say that marine animals are already subjected to tremendous stresses, and that it would be best to minimize additional challenges. So why not say so? Scientists can offer helpful answers, even in the absence of absolute clarity. But if we simply keep saying “the jury is still out”, we will be sentencing marine ecosystems to their demise.