A dynamic method to study the transmission of social foraging information in flocks using robots

To understand the mechanisms underlying the flow of social information in foraging groups, it is important to manipulate the behaviour of individuals and study the responses of flock members under different ecological and social conditions. Some studies have attempted this using three-dimensional models, like robots. Our goal was to assess the foraging and scanning behaviour of adult house finches, Carpodacus mexicanus, in response to robots mimicking different types of behaviours in artificial flocks (three linearly placed enclosures, with robots at the periphery and a live animal at the centre). We recorded whether live animals reacted to (1) the presence/absence of robots, (2) the motion of robots in relation to static robots, (3) variations in the type of robot behaviour and (4) the direction of the responses (increasing or decreasing their foraging effort). Adult house finches reacted differently to the presence, motion and behaviour of robots, and they spent more time foraging and less time scanning, which led to increasing seed intake, as the robots simulated body movement that could be associated with successful foraging behaviour (more handling time) or antipredator behaviour. Responses to robots were similar to those given to live conspecifics. We discuss advantages and disadvantages of using robots in social foraging research and conclude that robots are suitable to test some hypotheses on the foraging and antipredator behaviour of flocks. (c) 2006 The Association for the Study of Animal Behaviour Published by Elsevier Ltd. All rights reserved.