A recent paper in the Proceedings of the Royal Society correlates shipping noise with stress levels in baleen whales. Heretofore this has been a difficult assumption to prove because we do not have any baseline of whale stress levels prior to the introduction of the vast shipping networks we now use in global trade.
Researchers can get an idea of metabolic stress levels because they are correlated to hormone indicators (glucocorticoids) in body fluids. Rosalind Rolland with the New England Aquarium was studying the glucocorticoids in the feces of North Atlantic Right whale in the Bay of Fundy through September 2001. She was doing this research concurrently with a study on Right whale social behavior being conducted by Susan Parks with Penn State and Syracuse University.
Both of these studies overlapped the September 11 tragedy and the subsequent halting of air and sea transportation for a few days. It was across this time that the noise levels in the ocean decreased significantly. Parks, Rolland and other colleagues brought their work together and noticed a marked decrease in stress indicators with the decrease in shipping noise.
This is a real benchmark to our understanding of how chronic anthropogenic noise impacts baleen whales – which are too large to test in lab settings and not really interested in cooperating with behavioral scientists in the wild. Given that the glucocorticoids are part of a feedback mechanism in the immune system, this finding also confirms concerns that shipping noise compromises the health of these whales.
The paper is discussed in “lay” terms in a Science article that also introduces us to the critically important scientific instrument, a dog – whose nose can pinpoint whale feces in the ocean. (The dog was not included as a co-author on the paper.)
This paper should provide us with important supporting data as we attempt to slow industrial development in the pristine acoustic environment of Arctic.