Patterns of group movements in juvenile domestic geese

We investigated collective movements in a flock of domestic geese (Anser domesticus) to test the consistency of group orders and the influence of individual traits and social relationships on movement patterns. The subjects were 20 juvenile females kept in an herbaceous enclosure. Two observers continuously videotaped their movements. Although the positions of individuals might change during moves, the geese tended to hold predictable positions in different movements. We found that geese more reactive to unexpected noises more often held front positions. Moreover, the higher the associativity of a bird as measured by number of neighbors at rest, the more frequent the bird acted as first mover. The analysis did not evidence any influence of dominance status on the positions of geese during progression. In contrast, geese linked by close bonds clustered during progression. The structuring influence of social bonds in collective movements might be a general feature of animals gifted with individual recognition abilities.