Secret Squirrel Language Documented for the First Time
 Richardson’s ground squirrels, otherwise known in the Prairies simply as gophers, use an ultrasonic sound to warn others of impending danger.
“We discovered this quite by accident,” explains Dr. James Hare, a University of Manitoba zoologist. “There was a squirrel that stood up and opened its mouth and nothing came out. I thought she had lost her voice.”
The NSERC researcher was working with Annika Keeley, an undergraduate student with a passion for bats. Her equipment helped Dr. Hare determine that the squirrels did in fact emit a noise – an ultrasonic warning signal.
 Dr. Hare teamed with NSERC scholar David Wilson to research this ultrasonic scream, which they initially dubbed “whisper calling” because it appeared to be nothing more than a slight rush of air. The sound actually registered 70 decibels (equivalent to someone talking in a normal voice) and could be heard 15 metres from the source. Its high frequency makes it inaudible to the human ear.
“We are certain it serves an alarm function,” explains Dr. Hare. “This is the first time anyone has documented this.”
Dr. Hare and Mr. Wilson are conducting further research to learn more about how the squirrels use this sound. The high frequency and short range may act as a secret alarm, since some of the squirrels’ predators, which include hawks, owls, red foxes and badgers, either can’t hear high-frequency sound or would be too far away to pick up the signal.
Contact:
Dr. James Hare
Department of Zoology
University of Manitoba
Tel.: (204) 474-6379
E-mail: harejf@cc.umanitoba.ca
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