Rick,
The flight may not have been hovering from the strict definition of the term (like say a hummingbird), but the bird was essentially stationary.  While there was likely a headwind up the river, I do not recall it being "windy".  The position of the bird was similar to that of an eagle landing on its nest.  Talons were extended with its head looking down while flapping its wings at about a 45 degree angle relative to the ground.  Each flap was long and deep, but steady.  As the canvasback would briefly resurface the bird did not move horizonatally but would drop vertically a bit before rising up to about the same spot (about 5-6 feet about the ice).  This continued multiple times before eagle got the canvasback. It unfortunately lost his/her prize to another eagle.  I obviosly didn't anticipate this bird to hover and so I didn't time it, but it seemed to be somewhat of a prolonged event.  I'd say a minute would not be unreasonable.  Adam, who was with me, did mention that it reminded
 him of red-tailed hawk behavior.  I plan to do a literature search to see if anyone has documented this behavior before.  If anyone knows of any references, let me know.  I work at Patuxent Wildlife Research Center and am a graduate student and UMD, so I have access to most relevent journals.  I would be happy to share my results if anyone is interested.
 
Hope this is what you were looking for.
 
Dave Kidwell
Lothian, MD
   

Rick Sussman <> wrote:

In a message dated 1/26/2005 8:01:46 P.M. Eastern Standard Time, 
 writes:

The eagle hovered over the opening with the canvasback surfacing VERY 
briefly and diving again. This repeated several times, and the patient eagle 
continued to hover for well over a minute before finally grabbing the canvasback.


Dave,
I wasn't aware that eagles "hovered". Could you please elaborate on the 
behavior you saw?

Rick Sussman
Ashton,MD


		
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