Probably less than 8 percent of subscribers participated in the recent "Test
Your Hawk ID Skills" activity offered on several bird lists during the past few
days.
The remaining 90+ percent either didn't see or read the messages, could not
open the photos on their computers, did not feel qualified to participate or
would not participate for whatever reasons.
Results from 50 birders the compiler reported as participants, reveals that 45
persons (90 percent) correctly determined that the two photos were of a hawk
which is in the genus Accipiter. That was correct. That limited the
possibilities to Sharp-shinned Hawk, Cooper's Hawk and Northern Goshawk. The
goshawk was an obvious and easy species to rule out. The challenge was to
determine if it was a Sharp-shinned Hawk or Cooper's Hawk.
Sixty percent (60%) of the participants misidentified the bird.
The objective in this exercise was to ID it either as a Sharpie or a Cooper's.
Of those who misidentified the bird, a curious margin of 2 to 1 (2:1) did not
even guess it to be a Cooper's Hawk. Seventy-five percent (75%) of those who
got it wrong thought it was a Goshawk.
Accipters on the ground with or without prey are among the most difficult to ID
correctly. Many readers can imagine trying to correctly call a bird flying
thought the woods or across the road in front of our vehicle.
Having been a raptor bander for 44 years -- capturing and banding hundreds of
hawks --it's been a source of amazement at the high number of birders who
cannot correctly ID Accipters held in the hand. Even with field guides and
walking around the bird to inspect all the feathers, misidentifications are
frequent. Birds perched in trees can be almost as difficult.
Whether we think we know what Accipter the bird may be or not, banders
determine sex first in order to correctly ID the bird in hand. That is
accomplished by measuring the wing chord:
184 mm or less for a male Sharp-shinned
246 mm or less for a male Cooper's Hawk
185-215 mm for female Sharp-shinned
251 mm or more for female Cooper's Hawk
So the application becomes:
Sharp-shinned Hawk -- wing chord 215 mm or less, outer tail feather less than
12 mm shorter than longest tail feather.
Cooper's -- wing chord 220 mm to 290 mm. outer tail feather more than 13 mm
shorter than longest tail feather.
Goshawk -- wing chord 300 mm or more.
This is like the rule of thumb in ID of shorebirds where every skilled observer
with experience has long since learned that you have to age many of the more
difficult birds before you can ID them.
Most people with hawk expertise are those who watch Accipters turn on wind
currents as they soar above or watch them flapping high above and at some
distance. Distant birds can be more easily and more correctly called because we
use behavior and flight profile and not size. Little feather color and eye
color comes into play. Such observers have few skills with birds in the hand.
We owe appreciation to the sponsor and compiler for the "Test Your Hawk ID
Skills" activity. It was great fun and educational.
He especially did a commendable job of compiling the comments of all the
participants who got the ID correct and presenting us with their combined
comments. That was a good job.
The next time you have a marginal call on an Accipter under less than optimal
conditions, strengthen your own skills by saying it is too difficult to call.
Move on and take pride in knowing what you don't know. The simple facts are
enough. It would be better to report one bird correctly called under optimal
conditions than a half-dozen on a hunch with an uneducated guess.
Let's go birding......
Wallace Coffey
Bristol, TN
SHARP-SHINNED 20
NOR. GOSHAWK 15
COOPER'S 10
NOR. HARRIER 1
RED-TAILED 1
MERLIN 3
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