Results of Accipiter Photo Quiz - Part II of III
Comments in support for Cooper's (from two respondents):
* Wing shape - too narrow and two short without enough of a taper into
the secondaries; the lack of an exaggerated bulge along the tailing edge.
* Head and neck projection much further beyond leading edge of wings
* Tail is long and does not appear broad enough for Goshawk.
(However,one respondent in support of a Cooper's did acknowledge the
leftmost photo showed a broad tail that could possibly support a NOGO.) One
respondent noted "Goshawks have the longest tail of the accipiters but in
proportion it is the shortest looking."
* Breast streaking not dense or extensive enough.
* Overall body mass too skinny (Only one respondent in favor of
Cooper's made comment to body mass.)
Comments in support for Northern Goshawk:
* One respondent pointed out undertail coverts noticeably extend
beyond the feet - "I could find NO photos of flying Cooper's Hawk that show
this. Goshawk always show "big, fluffy" UTCs from the side, but I had never
bothered to notice how far they extend with relation to the feet."
* Tail: One respondent noted "the tail bands on the outer rects show
a definite down-angle with respect to the feather edge, instead of hitting
at a 90-degree angle. This would mean we are seeing 1/2 of the "chevron"
tail band that is a Goshawk trait." And yet another respondent in favor of
Goshawk noted: "Unfortunately the tail feathers are all folded tightly in
the photos, so that no light gets through them to help us see what is the
other clinching field mark I would be looking for if I were confronted with
a possible gos. That is the irregularity in the dark tail bars. The tail
bars form smooth lines with even edges in a Coop, but are jagged in a
goshawk. The jaggedness would be expected even if the bird is in the middle
of molting and some of the feathers are growing out." And a third
respondent added The unevenness of the tail feathers is most likely feather
damage (lost feather, broken tip, etc.), not wear, since a HY bird in
October has only been flying about 4 - 5 months. We used to measure the
amount of white on the tips of Coop rects in fall and spring, and the fall
birds usually still had very crisp feathers." One respondent in favor of a
Cooper's noted the tail length tended toward a NOGO: "..tail seemed further
away from the wings than the usual Coop."
* Streaks on underside - Several noted what appeared to be relatively
heavy breast streaking and as one respondent added ".. that can vary
dramatically." And further added "Coops usually have thin streaking, giving
them a white-chested look."
* Width of secondaries - Respondents' comments: "I also remember
being impressed repeatedly when I've seen goshawks overhead with how deep
the distance is in the secondaries from the front edge of the wing to the
back edge; in fact, most goshawks in my experience show even more of a notch
where the secondaries meet the body than Sibley does in his flight pictures.
Your photographs tend in that direction, but they look like the bird is
having such an easy time of it flying that the wings don't really need to
extend out far enough to show more of that notch."
* Body shape - No one commenting in support of NOGO indicated overall
body mass appeared too small for a NOGO. An interesting comment from a long
time observer "An old guide line I used to use, "If it looks like a flying
chicken, you have a gos!" (That's sure what it looks like.)" Another
respondent commented "Pete Dunne writes in his book Hawks in Flight (I think
that's the name of it) that if you see a hawk that first appears to be a
Redtail and then you realize it's an accipiter, you've got a Gos."
According to several resources, including Wheeler's "Raptors of Eastern
North America", and Liguori's "Hawks from every Angle", special caution is
needed when comparing underside plumage of soaring juvenile accipiters,
especially between Cooper's and NOGO. Laiguori's "Accipiter Pitfalls" for
plumage states that "..many goshawk display narrow streaking on the
underside and appear pale overall."
Although on rare occasions the Sharp-shinned and NOGO may exhibit a slight
dihedral when soaring, they most often times soar with wings flat. Cooper's
almost always soar with sight dihedral. When flapping, a NOGO exhibits less
motion at the wrist than in other accipiters and wings appear straighter.
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Brenda Tekin
Charlottesville, VA
"Leave behind what you find; if you must take something, take pictures."
Digital Photography, including Birds of Virginia:
http://www.birdsofvirginia.com
