Infrasound from the Okapi
Presented Feb.6-11 1992
American Association for the Advancement of Science (AAAS)
158th Conference - invited presentation Student competition award
Elizabeth von Muggenthaler
Old Dominion University
The okapi, an endangered, forest dwelling giraffid
possessing limited auditory vocalizations, produces copious infrasounds. Recordings were made of ten okapia Johnstoni at the San Diego Wild Animal Park In Escondido, California, and White Oak Plantation in Yulee,Florida. A Bruel and Kjaer recording system and a portable DAT recorder,Genrad microphones, and portable oscilloscope were used and the results studied using an Onosoki CF920 spectrum analyzer.
Frequencies of the infrasonic calls ranged from 9 to 70 hertz. Infrasonic communication correlates with the large-eared, heavynecked anatomical characteristics of the okapis and with their life style as rare, solitary, partially nocturnal animals living in dense habitats. The recognition that okapis, like elephants, whales and possibly rhinoceroses, may communicate at these low frequencies supports the hypothesis that many large mammals transmit information with Infrasound to a degree heretofore unappreciated.