Subject: Fwd: [Tweeters] Cooper's Hawk videos
Date: Oct 19 18:36:49 2012
From: Hank - karenhank at yahoo.com


I received this very interesting and informative e-mail (see below) in response to my post regarding videos of a Cooper' Hawk in my yard. After reading the e-mail and looking at a photo that I did not post with the first e-mail, I have concluded that the hawk was a Sharp-shinned Hawk. I appreciate the input that I received on this ID.

http://www.flickr.com/photos/ljcouple/8103654570/

Hank Heiberg
Lake Joy
Carnation, WA
karenhank at yahoodotcom



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> Hank, from your post; ?We concluded that it was a Cooper's Hawk rather than a Sharp-shinned Hawk based on size.?
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> Most raptor females are larger than the males. Our old Audubon Western Birds lists a Sharp-shined as 10-14 inches and a Coopers 14-20. The first number is the average size of a male. The second is the average size of a female. A male Cooper and a female Sharp-shinned are basically the same size. Only the extreme size difference is between a 10 inch male Sharpie and a 20 inch female Coop would allow us to judge competently by size.
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> A few years ago there was a discussion about the difference between Coops and Sharpies. Most ID tips speak to a round tail vs. square. Wide or narrow stripe on tail and leg size. Bud Anderson of the Falcon Research Group got involved. He stated the tail shape and the stripe width are only reliable after a molt. Wear and tear on a square tail could make it round and a wide stripe thinner. He suggested a better way was to look at the head in profile. A Sharpie?s head looks like it has a forehead of sorts with the beak protruding like a nose or is wearing a cap. A Coop?s head and beak looks like a continues line. Once we stated looking looking for this, Coops are easier for us to identify.
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> We are fortunate to have both Coops and Sharpies land on our fence. We haven?t been able to capture a male Sharpie or a female Coop. This combined picture has a juvenile male Coop and a juvenile female Sharpie with lines defining the head shape as Bud suggested. He has seen the picture and confirmed it is what he was referring to and our identification of the birds.
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> One of the pictures had the board?s width manipulated to be the same width as the board in the other. That makes the birds the same scale as the fence and to one another. The birds are, for all practical purposes, the same size as the numbers suggest.
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> <JuviieCoopersandSharpiewithlines[1][1].jpg>
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> We think the shape of the head of your hawk looks like a Sharpie. If you have any stills or more video, look for ones with the head in profile and see what you think.
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> If the hawk is the same sizes as the Robin, it would be a male Sharpie for sure. Larger a female.
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> Hope this is of help.
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> Bob & Bernie Meyer
> Renton
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