“Among the bird world’s most skillful fliers, Cooper’s Hawks are common woodland hawks that tear through cluttered tree canopies in high speed pursuit of other birds. You’re most likely to see one prowling above a forest edge or field using just a few stiff wingbeats followed by a glide. With their smaller lookalike, the Sharp-shinned Hawk, Cooper’s Hawks make for famously tricky identifications. Both species are sometimes unwanted guests at bird feeders, looking for an easy meal (but not one of sunflower seeds).” (excerpt from the Cornell Lab of Ornithology’s All About Birds)
My New Jersey Big Year has given me the opportunity to spend many more hours in the field and, as a consequence, the ability to see many, many more birds of the same species. It’s allow me, perhaps for the first time, to really compare individual birds and take note of their different sizes, markings, and coloration. One thing’s for certain – I have learned that even the best field guide is truly only a “guide” to bird identification and not the final word.
Light can be deceiving. The quantity, quality, and angle of available light can alter the apparent colors of a bird’s feather to nearly unbelievable levels, especially when viewing a bird from a distance without the benefit of a scope or bins (though light can play tricks with your views through them, too).
My photograph doesn’t do justice to this Cooper’s Hawk. I’ve tried to frame the photo to give you a hint to this bird’s size. This bird was, easily, 150 – 175 feet from the trail I was hiking. Honestly, this has to be one of the largest Cooper’s Hawks I have seen, ever. When I first saw it, I thought “Northern Goshawk?”. Yes, it was that large.
I first tried to examine it through my bins, but the distance to the bird and the available light made positive identification impossible. Next I scoped it and began to make out details that weren’t apparent through my bins. Even through the scope, though, the light played tricks with the bird’s coloration. Finally, I snapped several photos that I hoped would allow me time at home to examine the bird more closely.
Clearly, the bird is a Cooper’s Hawk. Though very large, the size is within the described range for this species. And the overall shape and color pattern (which was so hard to see in the field) matches that of a large Cooper’s Hawk, not a small Northern Goshawk.
Have you experienced these identification challenges in the field? Have distance and light levels played tricks on your birding eyes and brain?
Birds like this Cooper’s Hawk have taught me to go carefully through my guides (I carry two in birding bag and I am thinking of adding a third, larger guide to my “field library”) and, sometimes, delay indentification until I can go through my photos at home.
What strategies do you use to “get it right”? I’d love to hear about your experiences with tricky bird IDs. Drop me a line!
Until next time – Good Birding!