Humpback whales aren’t known for being the quietest animals in the ocean blue, but new research reveals that younglings certainly can be when it comes to survival.
Published in the journal Functional Ecology by researchers based out of both Australia and Denmark, the study illustrates how baby humpback whales, known as calves, actually ‘whisper’ to their moms to avoid predation.
Image Credit: Daviderich/Pixabay
While said whispering probably doesn’t sound the way it does when you and I whisper to others, calves communicate much more quietly with their mothers than fully-grown humpback whales do. The latter can be heard from tens of miles away underwater, while calves limit their sound volume so they can only be heard in close proximity; within 330 feet to be exact.
The team came up with the findings after attaching special tracking equipment to eight calves and two of the mothers. One of the features of the tracking equipment was recording audio, and the team consistently noticed that the calves were all speaking to their moms at lower volumes than typical adult humpback whales would when crying aloud; up to 40 dB lower.
By keeping their volume down, calves prevent unwanted listeners from keying in on their existence and location, which prevents them from becoming the prey of nearby predators, such as killer whales, which commonly go after baby humpback whales.
More importantly, the sounds that they emit are much less intense than those of adults too. While an adult’s cry may be deep and constant, the calves opt to make much subtler sounds like squeaks and chirps. Some examples of the sounds are demonstrated in the video below:
Perhaps the things they’re saying are, “Mom, I’m hungry,” or “Mom, where’s dad?” While we don’t know for sure what they’re trying to communicate, it goes without saying that it’s probably a very viable way for the calves to communicate with their moms when they sense danger or when they need food, and to do it without attracting attention.
This is reportedly the first time that such behavior has been documented in such great detail for humpback whales, and as a result, we now see their behavior is more complex than originally thought. Additional research could help us learn more about the communication and how it’s used to signal certain things to the mothers.