Airdate: May 18, 1999
Scientist: Phillip Whitford
CANADA GEESE- Neck Dip
For Canada geese, the spring dating ritual begins with a carefully timed neck dip.
CANADA GEESE - Neck Dipambience: Canada geeseHeres a program from our archives.Just as humans size each other up to see if we're compatible, so do other animals, such as Canada geese. They've developed their own complex courting behaviors. It's a kind of goose body language which helps to ensure that they don't end up mating with a different species. I'm Jim Metzner, and this is the Pulse of the Planet.Whitford: As the birds move into their breeding phase, sexual behavior always takes place on the water. It involves mutual neck dipping between the two members of the pair. They swim out, turn and face one another. And the male may begin neck dipping to the female and the female is to respond. And then it alternates for a period anything from ten seconds on up to two or three minutes or more.Phillip Whitford is an Associate Professor of Biology at Capital University in Columbus, Ohio. He tells us that by alternately dipping their heads under the surface of the water, male and female Canada geese indicate that they're ready for mating.Whitford: For years, people thought that neck dipping was synchronous, both birds sticking their necks under water at the same time. But if they did that, they wouldn't see each other do it. It's alternating: one bird then the other, one bird then the other. And as long as each one follows the code, they get to the end. It's sort of like like small talk that goes on at singles' bars between two individuals who don't know one another very well, but who are trying to get to know each another and reach the breeding stage. But you have to do everything right, or you don't reach the end of the sequence and there'll be no breeding, if things get out of synch. It's a means of preserving the integrity of the species, by preventing hybridization. If the male is one species and the female another, things don't proceed at the same rate; you end up with both heads under water at the same time; they both come up and they think the other hasn't responded. The birds do not breed.Weve been listening to a program from our archives. If you want to hear more, check out our podcast.Im Jim Metzner and this is thePulse of the Planet.