Sperm whales have a unique way of communicating their awareness of nearby ships. Researchers from Project Ceti have discovered that when sperm whales hear the noise of boats, they alter their 'codas' - distinctive patterns of clicks used for communication. These codas become shorter and one type becomes more prominent than another. The study, published in Ecological Informatics, found that sperm whales can predict the presence of ships based on these altered codas alone.
This finding raises intriguing questions about the nature of whale communication and its implications for policy and laws. David Gruber, the founder and CEO of Project Ceti, suggests that the whales might be discussing the ships or reacting to the impact of the ships on their voices. Gašper Beguš, the linguistics lead, notes that the whales seem to prioritize changing not just the speed but the types of codas they produce in noisy conditions.
The study builds on previous research by Project Ceti, which found that sperm whales use 'vowel-like' sounds in their communication. These vowel-like sounds, when condensed to speed up the recording, resemble the human vowels 'aaaa' and 'iiii'. In the presence of shipping noise, the whales change the way they use these vowels, indicating that they might carry meaningful information.
However, the study has faced criticism from some researchers who argue that the use of terms like 'vowels' and 'language' stretches the associations between whale and human communication too far. Nathan Merchant, an underwater noise specialist, suggests that there could be other unknown factors driving the change in whale vocalizations. Nonetheless, the study adds a new dimension to our understanding of how underwater noise affects cetaceans, and more research is needed to determine the meaning of these audible changes.
In conclusion, the discovery that sperm whales can predict the presence of ships based on altered codas is fascinating and has significant implications for our understanding of whale communication and its potential impact on marine life and human activities.
