Close your mouth, hold your breath and whistle
Marine mammals can do it, so why can’t we? A simple answer is because we don’t need to. If we open our mouth underwater we won’t drown, but a whale would.
Land mammals make noise by vibrating their vocal folds as they exhale air. Whales don’t have vocal chords. In this 4-minute video, Professor Tracey Rogers explains that whales and dolphins have soft tissues in their nasal passage over which they funnel air, which is kind of like whistling through your nose.
Except they don’t have noses. Marine mammals have an exhalation hole – a blow hole – which is closed off when they are underwater: lock the hatch and dive, so to speak. To open their mouths underwater they seal up their throat with their enormous tongue, making exhalation impossible. For baleen whales, the humpback and the great right whale, this seal helps them swallow tonnes of krill in each mouthful without swallowing water.
So how do they funnel the air? Where do they funnel the air?
Baleen whales need tons of krill every day.
Whales and dolphins have evolved to recycle the air they breath numerous times between their lungs and various air-sacks in their body. This also means that they do not have to come to the surface to breath every time they want to communicate, adding new meaning to the phrase ‘they didn’t even stop to draw breath’.
Marine mammal communication is further facilitated by the density of water, making sound travel underwater four times as far as it does on land. High-pitched sound is easier to hear than lower noise, but marine mammals have access to a full and varied array of sounds, from bass rumblings to clicks and whistles. They are great communicators.
Here at Gowings Whale Trust we are guessing that some of the conversation might be asking us to stop polluting their home. They’ve been recycling for centuries – why can’t we?
Find out about Gowings Whale Trust mission to recycle plastics.