Rob,

We saw an adult eagle catch a Bufflehead on Lake Washington a few years ago, so some eagles learn how to catch them, and/or this was a Bufflehead at the low end of the predator-escape curve. Coots and Western Grebes seem particularly susceptible to the eagle methods of hunting diving birds.

Dennis

On Feb 29, 2012, at 8:28 PM, Rob Sandelin wrote:

> I was out at Double bluff park on Whidbey Island today. I walked about 3 miles south and a Juv. eagle spent the better part of 20 minutes seriously trying to grab some bufflehead for lunch. About a dozen feisty little ducks easily out maneuvered the predator and it was like a game of whack a mole, only played by somebody really slow. The eagle was using the wind to soar aloft and when it dove for a duck, they would dive, then as the eagle regained a bit of altitude they would all pop up within a few seconds of each other. It appeared the eagle had a hard time singling out a victim although I noticed that the ducks were all pretty evenly spaced apart, yet still close enough to be a sort of group. After several minutes of not even coming close I thought the eagle would give up. It did soar higher and off shore a bit, then dropped down and rode the wind really fast and low to the water. That didn?t work either. As I was walking back I came across a group of mallards, which surprised me as I rarely see them on Salt water. I would imagine those would have been a much easier target. I wondered about what the predator prey identification learning curve is. Do eagles discriminate between species, learning which ones are easier to catch? If so, today?s eagle learned Buffleheads are not a good choice.
>
> Rob Sandelin
> Naturalist, Writer, Teacher
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-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net



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