Singing Without Vocal Cords
Aloha,
The trade winds were blowing for our two Tuesday Whale Watch Cruises from Kawaihae. On our Wake Up with the Whales Cruise, we had to travel waaaay north of the harbor before we saw our first Humpbacks. These two passed pretty close by our idling boat a couple of times. They were definitely in synch with each other, surfacing, spouting and lifting their flukes to sound simultaneously. When they were underwater, we deployed our hydrophone and we got a chance to eavesdrop on them. On our way back to the harbor we saw a Mom/Baby pair, but we couldn’t stop to watch them for very long because one of the interisland barges was right behind us and we had to kick into high gear to get into the harbor before they did.
When we left the harbor on our Late Morning Whale Watch Cruise we saw some splashing at the surface just about 1/2 mile away, so Captain Sam took us over to investigate. The commotion turned out to be from a competitive pod of 4 whales who kept at it for our entire cruise. We saw multiples of pretty much every surface behavior except for spy hopping and breaching — we watched the whales pec slapping, tail lobbing, peduncle throwing, head lunging, bashing into each other, and motor boating. We even got to see them inflate their mouths as they traveled (definitely an aggressive behavior — a way to make themselves look bigger than they already are). The wind was blowing too hard for us to deploy the hydrophone, but that was ok, because there was always something to watch.
Mahalo,
Claire
Ocean Sports Whale Fact of the Day: When we deploy our hydrophone (or put our heads below water) during the wintertime, we’re always fascinated by the sounds we hear the Humpbacks making. We know they don’t produce sounds the way we do — in order to sing or talk, we pass air over our vocal cords. If we could do this underwater, bubbles would rise from our mouths to the surface. When our Humpbacks vocalize, no bubbles rise to the surface, and in fact, Humpbacks don’t have vocal cords like we do — so how do they produce those haunting sounds? Last year, researchers at the University of Southern Denmark experimenting on deceased beached Sei, Minke and Humpback whales took a look in these whales’ larynxes and found a U-shaped tissue and a large “cushion” of fat and muscle not found in other animals. They found that when they blew air across the fatty U-shaped folds, it pushed those folds against the fat and muscle cushion, creating vibrations that actually matched the sounds that the living whales make in the wild. So…that’s HOW the whales sing, but exactly WHY they sing is still under investigation.