Falmouth researchers discover new information about whale songs
Several Falmouth-based researchers have gained more insight into the songs of the humpback whale.
When a whale sings, physical vibrations can be felt around the animal. A team of researchers from the Woods Hole Oceanographic Institution found that these vibrations, known as particle velocity, can be felt much farther away than originally thought.
“Particle velocity is kind of the long bass that you feel when a car is approaching you. You can hear the sound far away, but you can also feel the vibration,” said Aran Mooney, a Woods Hole biologist. “But sound doesn’t travel as well in air as it does in water.”
In a paper published Wednesday in the journal Biology Letters, the Woods Hole team detailed their findings from studying a group of humpback whales off Maui. Mooney said they measured vibrations from about 200 meters away from the whales but believe they could be felt as far as one kilometer away.
“It’s always thought of as this part of sound that happens really close to a source, but not usually very far away, so we were kind of expecting it to not be very substantial,” Mooney said. “But if you stuck your head over the side of the boat, you could hear them loud and clear.”
The paper stated that “whales could potentially use such information to determine the distance of signaling animals. Additionally, the vibratory nature of particle velocity may stimulate bone conduction, a hearing modality found in other low-frequency specialized mammals.”
“We don’t know yet if they use it for communication, but we think so,” Mooney said. “That’s the next step.”
Mooney said that only male humpbacks sing but that it doesn’t appear to be for mating purposes.
“We think it’s a way of males communicating with each other,” he said. “We know that females are not attracted to it, but we know that males respond to other singing males.”
The discovery marks a step forward, but researchers still have much to learn about whale communication, Mooney said.
“We want to play back the recordings and see if whales swim back toward it,” he said. “That’s the next step.”