Hi, I see this picture on the Boat-tailed Grackle page of the Cornell bird website (http://www.allaboutbirds.org/guide/boat-tailed_grackle/id)
But I think it looks more like a Great-tailed Grackle. See its yellow eyes and flat head. They are expert, so they are probably right. But I'm confused. How to tell Great-tailed Grackle from Boat-tailed Grackle then?
Thanks,
Cui
The site credits give "© Brian Kushner, DE, Dutch Neck Crossroads, October 2012" - Great-tailed is highly improbable on the Delaware coast. The Atlantic Coast populations of Great-tailed have light eyes, it's only the Gulf Coast where they have dark eyes; so that's not a problem. Head shape is more difficult to decide, it doesn't look especially flat to me, but it's open to personal interpretation.
And yes, telling the two apart from a photo at an unknown location is very tricky ;-)
Hope this helps!
Resin
OK. I'm relieved that it's tricky even for Resin ;) Fortunately their ranges don't overlap too much. It seems that the best way to tell these two species apart is from the location information. Could you give me more such examples (where it's hard to tell two apart without the location information)?
Thanks,
Cui
A simple search can help. This is just one of many sites out there.
http://feederwatch.org/learn/tricky-bird-ids/
And study your field guide, if you have one. Some will place similar birds together and explain how they are different.
