Apr
05
2010

My House Hawk

image001

This is interesting.  We ID birds 200 feet in the air, with backlight conditions, moving in circles and we are incredibly confident in our calls.  Here is a bird, sitting in a small leafless tree in my front yard, “captured”, enlarged and cropped, and we have three or for pretty good birders not quite sure of it’s kind.  Of course John Audubon would know what it “was”.  I say was because he would have shot it, stuffed it and mounted it before he painted it and named it.  Chucky D would probably not know this bird since its range does not include any areas visited by him,  but he would be the first to bring up VARIATIONS.  I recently enjoyed reading the new Dawkins book–The Greatest Show On Earth, and he talks of rabbitness. That is, we all try to explain what the ideal rabbit looks like, but we know deep in our biological souls that there is no perfect rabbit! There is a spectrum of rabbitness. Of course we can look at a hawk and suggest that it is a Coopers Hawk or a Red Shouldered Hawk or a Sharpy, or ……..     We know there is no perfect Cooper or Sharpy that portrays all the characteristics of the Coopers Hawk species. There is Coopers Hawkness or Sharpyness that lies somewhere on a spectrum of characteristics and we deem the bird a Coopers ( or Red Shouldered, or what have you!) So how do the great birders always “get it right?”   First, they don’t always get it right, and second, they use more than just field marks and colors.  They combine marks and colors and patterns and maybe most importantly–behaviors.  That is what my picture is missing–behaviors.   The success of good bird identification is not simply knowing what a bird looks like, it is also knowing what it is doing, how it is behaving.  Maybe the pinnacle of bird spotting is on the top of Hawk Mountain in East Central Pennsylvania.  During the Fall migration hundreds of hawks of various species can be seen.  Think about Darwin’s variations with this scene–  50 or 60 Cooper’s Hawks or over 1600 Broad-winged Hawks that were spotted last September 17th.  Which one was the perfect Broadwing?   How did the spotters know all 1600 were really Broadwinged Hawks?  It is what Barbara McClintock called  ”a feeling for the organism.”  On this same day a total of  1646 hawks of various species passed by Hawk Mountain.  A total of 8 different species of raptors were recorded.  The total for the whole 2009 migration season was  15,592 birds, 21 identified species and 1 in the category “other”.  (I wonder what “other” was.  Is this the only bird they could not identify???)   As I looked over this data I thought about Dawkin’s species problem, the perfect Red Tail, or Cooper, or Bald Eagle.  I also pictured the bell-shaped curves that Darwin’s variation concept predicted.  In fact, I even pictured bell-shaped curves soaring past the North Lookout of Hawk Mountain.  Hawk Curve.001Well, not really, but now that I wrote about it I cannot get the image out of my mind!!   So there it is.  One hawk, one picture, a waterfall of thoughts.

DSC_2272 - Version 2

The young Red-Shouldered returned a few months later and brought along a partner

.  Now I watch them both as they pick off a series of moles and chipmunks that wander along the forest edge in my backyard.

What a lesson in evolution I have unleashed because a young hawk decided to take a rest at 10437 Misty Ridge Drive!!