By Lily Melendez
Preserving the Voices of Whale Species
Prior to the 1970s, approximately 50,000 whales were hunted commercially each year. Historically, these whales, including the humpback and bowhead, were central to global sustenance, providing sources for oil, cosmetics, and fertilizer (Lang, “Detailed Discussion”). However, many overlooked the implications of studying these organisms and the voices they hold. Analyzing the tonal qualities and frequencies of their distinctive voices, scientists have been able to better understand the evolution of these mammals, their unique behaviors, and how changes in climate affect their means of communicating. It is essential to consider these non-human voices to more effectively grasp how humans can engage in practical environmental conservation efforts to sustain a voice that has been historically disenfranchised to speak.
Particularly, whales utilize various rhythmic and frequency alterations that can be interpreted as signals of kinship as well as changing environments. Often times, whales, such as the Caribbean sperm whales, create clicks, or codas, bursts of high pitched sounds to establish social ties (Sartore, “Whales with Caribbean Accents”). The whales are able to recognize familiar clicking patterns, and thus, engage in safe interactions with whales they can mate with as opposed to unsafe inbreeding. In a similar way, baleen whales can project a deep, long-distance pitch to signify their location to their trusted kin if they are ever too far from reach (“How Do Whales Communicate”). In spite of these evolutionary assets of their vocal prowess, whale species are having more trouble conducting these forms of communication due to chemical and physical changes in their oceanic regions.
Considering separate recordings of arctic whales from different decades, one can perceive distinct changes in pitch and rhythm. According to a study conducted by Jean-Yves Royer, a geophysicist at the French National Centre for Scientific Research, comparisons of baleen whale songs from 2002 to 2015 demonstrate that “the sound frequency changed in areas where icebergs melt due to warmer water and air” (Borenstein,“Whale Songs and War”). In effect, the baleen whales are forced to strain their voices and deepen their songs to be heard over the roaring sounds of breaking ice. Although this issue of vocal presence may appear small in the wider scale of climate change, this environmental change carries drastic consequences for the preservation of whale communities as communication is integral to their way of life.
Moving away from colder whale-inhabited areas, there is also evidence of whales lowering their vocal tones due to other climate change complications. Viewing a study of the changing soundscape of the Indian Ocean, scientists found many whales were dropping in vocal frequency (as denoted in hertz). They were led to believe this falling of call intensity could be equated with the “increasingly acidic” chemistry of the waters as sound travels farther in water with higher carbon dioxide levels (Leroy, “Long-Term and Seasonal Changes”). Having to increase or decrease their normal pitch volumes is just one of the many restrictions whales face in an increasingly shifting ecosystem.
Restrictions on their voices could prove dire to whales that rely heavily on sound to locate mates, navigate, hunt, and behave with others. Upon listening to whales even of the same species, it is clear that whales speak much like humans do. There are often varying tonal quality, specifically with regards to the speed and intonation of certain sounds, that individual whales bear to separate themselves out from a pod. Essentially, whales have the capacity to distinguish themselves as individuals, which is useful in identifying who is speaking and necessary for whale mothers to keep track of their multiple children while migrating. Taking into account their application of voice, more research and preservation efforts should be conducted to uphold the welfare and lifestyles of these highly communicative species. The oceans, like the air we are surrounded by, are the whales’ soundscapes, and we are directly responsible for protecting the instrument through which they survive.