Print

Print


In Sibley's Guide to Birds on p. 300 at the bottom of the page is a 
description of the wing shape. "Narrow tip of outer primaries produce trill 
in flight.  Trill may be faint or absent if tips are worn (often Nove-Jan)."

He doesn't explain how, but perhaps it is a subtle intensity of movement? I 
checked Lanny Chambers' website, and couldn't find an explanation there 
either.  www.hummingbirds.net


Margy Terpstra
Kirkwood, St. Louis Co MO
[log in to unmask]

----- Original Message ----- 
From: "Kathleen Anderson" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, June 16, 2008 3:05 PM
Subject: broad-tailed hummingbird


>I would be interested in how the broad-tailed hummingbird produces the wing 
>whir
> and how it can "turn it off".
>
> Kathleen Anderson, Columbia
>
> ------------------------------------------------------------
> The Audubon Society of Missouri's Wild Bird Discussion Forum
> Questions or comments? Email the list owners:
> mailto:[log in to unmask] 

------------------------------------------------------------
The Audubon Society of Missouri's Wild Bird Discussion Forum
Questions or comments? Email the list owners:
mailto:[log in to unmask]