caa a22 4500 463175522 CHVBK 20180406164825.0 cr unu---uuuuu 170326e20071201xx s 000 0 eng 10.1007/s10336-007-0199-0 doi (NATIONALLICENCE)springer-10.1007/s10336-007-0199-0 Head-bobbing behavior in walking whooping cranes ( Grus americana ) and sandhill cranes ( Grus canadensis ) [Elektronische Daten] [Thomas Cronin, Matthew Kinloch, Glenn Olsen] 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. Dt. Ornithologen-Gesellschaft e.V., 2007 Head-bobbing nationallicence whooping crane nationallicence Sandhill crane nationallicence Avian vision nationallicence Visual fixation nationallicence Visual search nationallicence Cronin Thomas Department of Biological Sciences, University of Maryland Baltimore County, 21250, Baltimore, MD, USA aut Kinloch Matthew Department of Biological Sciences, University of Maryland Baltimore County, 21250, Baltimore, MD, USA aut Olsen Glenn USGS Patuxent Wildlife Research Center, 20708, Laurel, MD, USA aut Journal of Ornithology Springer-Verlag 148(2007-12-01), 563-569 0021-8375 148<563 2007 148 10336 https://doi.org/10.1007/s10336-007-0199-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10336-007-0199-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Cronin Thomas Department of Biological Sciences, University of Maryland Baltimore County, 21250, Baltimore, MD, USA aut NATIONALLICENCE 700 1- Kinloch Matthew Department of Biological Sciences, University of Maryland Baltimore County, 21250, Baltimore, MD, USA aut NATIONALLICENCE 700 1- Olsen Glenn USGS Patuxent Wildlife Research Center, 20708, Laurel, MD, USA aut NATIONALLICENCE 773 0- Journal of Ornithology Springer-Verlag 148(2007-12-01), 563-569 0021-8375 148<563 2007 148 10336 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer