With as much effort that has gone into understanding how noise impacts marine mammals − and all of the contention that orbits around setting appropriate exposure mitigation levels, we still know very little about which noises (and how much) have a negative impact on marine animals.
One of the challenges is that while countless studies of animal responses to sound have been performed over the decades, a preponderance of this research has been conducted in lab settings where predictability reigns. Unfortunately while the predictable studies do tell us something, they don’t replicate the range of variables found in live, natural settings. And arguably captive animals are poor proxies for animals found in the wild.
But to study animals in the wild requires interacting with them. In some cases these interactions can be qualified as “harassment,” and many scientific studies have been thwarted or constrained due to this antagonistic component of the study.
The problem is that we’ve been running into a data desert just as our colonization of the sea threatens to transform the acoustic environment forever − at which point we may never really know.
What we do know is that there are sounds made by humans that in quality, amplitude, and scale do harass and even kill marine animals. Unfortunately not knowing the mechanisms of negative sound interactions does not prevent human commercial, industrial, or military activities from moving ahead.
OCR friend and colleague Brandon Southall from Southall Environmental Associates (SEA Inc.) is addressing this information shortfall with a multi-year Behavioral Response Study. By tagging whales with data recorders their live responses can be recorded under various situations, including exposure to potentially disruptive sounds.
The compassionate position against this type of research orbits around not wanting to harass wild animals for any reason. It was through this argument that similar “Controlled Exposure Experiments” were constrained or prevented from occurring in the past.
But it is rapidly becoming evident that if we don’t know what does bother marine animals, precaution will not prevail; industry and military operations in the sea will not be quelled by compassionate speculation.
So under the rubric of the “balance of harms,” SEA Inc. is in the midst of a comprehensive five-year study on how marine animals respond to noise exposures. It is also clear from their methodology that the last thing they want to do is harm the magnificent creatures that they are studying.
We’re all looking forward to the results of these studies, and the positive impacts they will have on ocean conservation policies.