Dr. Michael Pardo, a post-doctoral research fellow in the Department of Fish, Wildlife and Conservation Biology at Colorado State University, has hired Bag End to build a custom loudspeaker for elephant field research.
Dr. Pardo, with his custom Bag End subwoofer, is currently leading an exploration of vocal communication in African Elephants. Fieldwork is taking place in Samburu National Reserve, Kenya. He is investigating the function of vocal learning ability in wild African Savannah Elephants, including the possibility that elephants call one another by name.
One of the elephants’ call types, the “rumble”, is the most common and acoustically variable. Large vocal production anatomy is responsible for the low-frequency of the rumbles, with frequencies in the infrasonic range. Long-distance communication is thought possible because low-frequency sounds degrade more slowly over distance than high-frequency sounds, and elephants respond to rumbles produced more than a mile away. In addition, elephant ear anatomy allows them to detect low frequencies. Experiments demonstrate that elephants can detect infrasonic tones and discriminate small frequency differences. There is evidence that the structural variation in rumbles reflects the individual identity, reproductive state, and emotional state of callers.
