The jury still seems to be out on the biological impacts of seismic airgun surveys. While there is ample evidence of migratory, feeding, communication, and other behavioral disruptions in marine mammals, and habitat and dispersal disruptions in fish – along with compromised catch abundance, there has never been an unequivocal correlation between seismic surveys and marine mammal mortality (which seems to be required before the public flicks off the switch).
Exacerbating this situation is the tenacity of a “true” but systematically false statement issued a few years back by Bureau of Ocean Energy Management (BOEM) Chief Environmental Officer William Yancy Brown that “There has been no documented scientific evidence of noise from air guns used in geological and geophysical seismic activities adversely affecting marine animal populations…” The statement is “true” because there are no scientific studies of seismic survey impacts on marine animal populations.
And should you want to design a population impact study, you would need to isolate all of the other stressors in the system to make sure the surveys were the only factor affecting your observations. This is a little difficult in geographically large areas subject to all sorts of other stressors – from chemical pollution, to food supply competition (among other factors).
So now that we are facing the full force and obligations of our National Executive Branch, and the many bought voices in our Legislative offices to advance a fossil fuel agenda regardless of the costs, where do we stand?
A recently published peer-reviewed paper reveals high mortality in marine zooplankton (40% to 60%) in the wake of seismic airgun surveys. While none of these critters are “protected” under the Endangered Species Act, and they are certainly not marine mammals protected under the Marine Mammal Protection Act, they are the foundation of the ocean’s zoological food chain – feeding not only the great whales, but also corals, barnacles, oysters, clams, shrimp, forage fish, and other marine life that we humans depend on for our own food supply.
So all sentimentality aside; the fact that seismic surveys compromise the food chain at the foundation of our own food supply should be a clear enough reason to not permit seismic airgun surveys.
Unfortunately, the oilmen have their hand on the throttle at the moment and don’t seem interested in surrendering. So it is up to us – the informed public, to show up and drive the seismic survey discussion.