Threat assessment by domestic ducklings using visual signals: implicationsfor animal-machine interactions

There are increasing opportunities for robots to work amongst animals in ag ricultural systems. One potential application is in herding animals prior t o catching or transportation. An effective herding robot must be able to in terrupt ongoing animal behaviour without causing panic or flight reactions. The extent to which different approaching stimuli interrupted the feeding behaviour of pairs of domestic ducklings was examined to assess their suita bility as herding stimuli. Experiment 1 assessed the responses of ducklings to an approaching human (the most likely current herding stimulus), a vert ical cylinder (a stimulus with the minimum features of a simple robot) and a model fox (simulating the more natural features of a predator). Interrupt ion of feeding was greatest in response to the human and least to the cylin der. Experiment 2 found no significant difference in the extent to which fe eding was interrupted when facial appearance and head orientation of the mo del fox were manipulated. Experiment 3 examined whether biologically realis tic features of the model fox affected duckling response. At a distance of 7 m, photographs of the model fox interrupted feeding behaviour as much as the model itself. However, at a distance of 1 m, the model fox caused signi ficantly more feeding interruption than an intact photograph. A fragmented photograph caused the least interruption of feeding behaviour. (C) 2000 Els evier Science B.V. All rights reserved.