As fall quickly descends upon the Northeastern United States, flocks of Canada geese are getting ready to migrate. But how does each group decide when to begin its journey? It turns out that this choice is not random—one goose doesn’t just start the cascade whenever he or she feels like it.
Biologist and blogger Africa Gomez points to a 1969 paper by Dennis Raveling, in which Raveling studied the behavior or flocks before takeoff. Gomez writes:
Flock departure was preceded by a ceremony, with the neck stretched, there are quick head tossing movements with the bill pointing up and repeatedly, and the white head patch conspicuously displayed – communicating an intention to fly. Geese often spread and flap their wings and start to walk in the intended direction of flight for a few steps (this video illustrate this behavior). Ganders (adult male geese) were more successful at recruiting his family than any other family members, as a shorted time elapsed from his initiation of head-tossing until the family took flight, although all family members initiated head tossing at some point. In a couple of occasions when an excited immature took flight but the rest of the family did not follow, it flew in a circle and returned with the family shortly.
Here’s the video she mentions. The upshot is: when a goose wants to scram, he or she has to recruit the rest of the flock to go with them. In the movie Fly Away Home, the recruitment process involved a goose-shaped plane, but in the wild it’s just a few flicks of the neck.
Update: We’ve been informed that we should be calling these geese Canada geese, not Canadian geese. Here’s the argument for using Canadian geese, but, since we’re fans of history around here, we’ve changed it to the original Canada.
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