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USGS · 70031398

Head-bobbing behavior in walking whooping cranes ( Grus americana ) and sandhill cranes ( Grus canadensis )

Thomas W. Cronin·Matthew R. Kinloch·Glenn H. Olsen
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Abstract

Head-bobbing is a common and characteristic behavior of walking birds. While the activity could have a relatively minor biomechanical function, for balance and stabilization of gait, head-bobbing is thought to be primarily a visual behavior in which fixation of gaze alternates with a forward movement that generates visual flow. We studied head-bobbing in locomoting whooping cranes ( Grus americana ) and sandhill cranes ( Grus canadensis ), using food strewn on the ground to motivate them to walk or run. When the cranes walked, head-bobbing proceeded in a four-step sequence that was closely linked to the stepping cycle. The time available for gaze stabilization decreased with travel speed, and running cranes did not head-bob at all. As a crane extended its bill towards the ground for food, it also exhibited a series of short head-bobs that were not associated with forward travel. Head-bobbing is a flexible behavior that varies with gait and with visual search, most notably as the cranes prepare to strike with the bill.

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Thomas W. Cronin, Matthew R. Kinloch, Glenn H. Olsen. 2007-08-09. Head-bobbing behavior in walking whooping cranes ( Grus americana ) and sandhill cranes ( Grus canadensis ). https://doi.org/10.1007/s10336-007-0199-0

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