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Name: Janet C.
Status: educator
Age: old
Location: N/A
Country: N/A
Date: 1999-2001

We have two swans on a small lake by our house. They will make noise, like a loud trumpeting sound,while making their necks go up and down. Why do they do this? Sometimes they flap their wings and almost run on the water. What is the significance of this? They actually killed two geese in the lake by holding them underwater. Is this usual behavior? I have read some of the articles and they don't mention this behavior. Thanks

Trumpeting and neck bobbing are displays, part of establishment of territory and courtship. "running" over the water might be an aggressive display to other birds, especially geese. Swans are usually very aggressive toward geese and are often kept in corporate park and golf course lakes to help drive away geese.

J. Elliott

Most birds use a series of behaviors to reinforce the bond between the mated pair. In the spring before the nesting, these behaviors is most apparent for this is the signals that the species use to prepare and execute the mating process, and all through the time that the young are being attended these behaviors will continue to lesser degree. What you observed is typical swan behavior.

Both Canada Geese and Trumpeter Swans are aggressive species. Very aggressive, even toward humans. They will not tolerate competition in their nesting area. Swans being larger will have the upper hand and I am not surprised that the Geese were injured or killed. The Geese were nesting within the swan's territory I presume. I have not seen or heard of Geese being killed, usually they just leave when challenged, but I am not surprised due to their aggressive behavior.

Steve Sample

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